vendor/go.opentelemetry.io/otel/.golangci.yml

+# See https://github.com/golangci/golangci-lint#config-file
+run:
+  issues-exit-code: 1 #Default
+  tests: true #Default
+
+linters:
+  # Disable everything by default so upgrades to not include new "default
+  # enabled" linters.
+  disable-all: true
+  # Specifically enable linters we want to use.
+  enable:
+    - deadcode
+    - depguard
+    - errcheck
+    - godot
+    - gofmt
+    - goimports
+    - gosimple
+    - govet
+    - ineffassign
+    - misspell
+    - revive
+    - staticcheck
+    - structcheck
+    - typecheck
+    - unused
+    - varcheck
+
+issues:
+  # Maximum issues count per one linter.
+  # Set to 0 to disable.
+  # Default: 50
+  # Setting to unlimited so the linter only is run once to debug all issues.
+  max-issues-per-linter: 0
+  # Maximum count of issues with the same text.
+  # Set to 0 to disable.
+  # Default: 3
+  # Setting to unlimited so the linter only is run once to debug all issues.
+  max-same-issues: 0
+  # Excluding configuration per-path, per-linter, per-text and per-source.
+  exclude-rules:
+    # TODO: Having appropriate comments for exported objects helps development,
+    # even for objects in internal packages. Appropriate comments for all
+    # exported objects should be added and this exclusion removed.
+    - path: '.*internal/.*'
+      text: "exported (method|function|type|const) (.+) should have comment or be unexported"
+      linters:
+        - revive
+    # Yes, they are, but it's okay in a test.
+    - path: _test\.go
+      text: "exported func.*returns unexported type.*which can be annoying to use"
+      linters:
+        - revive
+    # Example test functions should be treated like main.
+    - path: example.*_test\.go
+      text: "calls to (.+) only in main[(][)] or init[(][)] functions"
+      linters:
+        - revive
+  include:
+    # revive exported should have comment or be unexported.
+    - EXC0012
+    # revive package comment should be of the form ...
+    - EXC0013
+
+linters-settings:
+  depguard:
+    # Check the list against standard lib.
+    # Default: false
+    include-go-root: true
+    # A list of packages for the list type specified.
+    # Default: []
+    packages:
+      - "crypto/md5"
+      - "crypto/sha1"
+      - "crypto/**/pkix"
+    ignore-file-rules:
+      - "**/*_test.go"
+    additional-guards:
+      # Do not allow testing packages in non-test files.
+      - list-type: denylist
+        include-go-root: true
+        packages:
+          - testing
+          - github.com/stretchr/testify
+        ignore-file-rules:
+          - "**/*_test.go"
+          - "**/*test/*.go"
+          - "**/internal/matchers/*.go"
+  godot:
+    exclude:
+      # Exclude sentence fragments for lists.
+      - '^[ ]*[-•]'
+      # Exclude sentences prefixing a list.
+      - ':$'
+  goimports:
+    local-prefixes: go.opentelemetry.io
+  misspell:
+    locale: US
+    ignore-words:
+      - cancelled
+  revive:
+    # Sets the default failure confidence.
+    # This means that linting errors with less than 0.8 confidence will be ignored.
+    # Default: 0.8
+    confidence: 0.01
+    rules:
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#blank-imports
+      - name: blank-imports
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#bool-literal-in-expr
+      - name: bool-literal-in-expr
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#constant-logical-expr
+      - name: constant-logical-expr
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#context-as-argument
+      - name: context-as-argument
+        disabled: false
+        arguments:
+          allowTypesBefore: "*testing.T"
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#context-keys-type
+      - name: context-keys-type
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#deep-exit
+      - name: deep-exit
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#defer
+      - name: defer
+        disabled: false
+        arguments:
+          - ["call-chain", "loop"]
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#dot-imports
+      - name: dot-imports
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#duplicated-imports
+      - name: duplicated-imports
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#early-return
+      - name: early-return
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#empty-block
+      - name: empty-block
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#empty-lines
+      - name: empty-lines
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#error-naming
+      - name: error-naming
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#error-return
+      - name: error-return
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#error-strings
+      - name: error-strings
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#errorf
+      - name: errorf
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#exported
+      - name: exported
+        disabled: false
+        arguments:
+          - "sayRepetitiveInsteadOfStutters"
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#flag-parameter
+      - name: flag-parameter
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#identical-branches
+      - name: identical-branches
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#if-return
+      - name: if-return
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#increment-decrement
+      - name: increment-decrement
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#indent-error-flow
+      - name: indent-error-flow
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#import-shadowing
+      - name: import-shadowing
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#package-comments
+      - name: package-comments
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#range
+      - name: range
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#range-val-in-closure
+      - name: range-val-in-closure
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#range-val-address
+      - name: range-val-address
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#redefines-builtin-id
+      - name: redefines-builtin-id
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#string-format
+      - name: string-format
+        disabled: false
+        arguments:
+          - - panic
+            - '/^[^\n]*$/'
+            - must not contain line breaks
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#struct-tag
+      - name: struct-tag
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#superfluous-else
+      - name: superfluous-else
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#time-equal
+      - name: time-equal
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#var-naming
+      - name: var-naming
+        disabled: false
+        arguments:
+          - ["ID"] # AllowList
+          - ["Otel", "Aws", "Gcp"] # DenyList
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#var-declaration
+      - name: var-declaration
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#unconditional-recursion
+      - name: unconditional-recursion
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#unexported-return
+      - name: unexported-return
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#unhandled-error
+      - name: unhandled-error
+        disabled: false
+        arguments:
+          - "fmt.Fprint"
+          - "fmt.Fprintf"
+          - "fmt.Fprintln"
+          - "fmt.Print"
+          - "fmt.Printf"
+          - "fmt.Println"
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#unnecessary-stmt
+      - name: unnecessary-stmt
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#useless-break
+      - name: useless-break
+        disabled: false
+      # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#waitgroup-by-value
+      - name: waitgroup-by-value
+        disabled: false

vendor/go.opentelemetry.io/otel/.lycheeignore

+http://localhost
+http://jaeger-collector
+https://github.com/open-telemetry/opentelemetry-go/milestone/

vendor/go.opentelemetry.io/otel/.markdownlint.yaml

+# Default state for all rules
+default: true
+
+# ul-style
+MD004: false
+
+# hard-tabs
+MD010: false
+
+# line-length
+MD013: false
+
+# no-duplicate-header
+MD024:
+  siblings_only: true
+
+#single-title
+MD025: false
+
+# ol-prefix
+MD029:
+  style: ordered
+
+# no-inline-html
+MD033: false
+
+# fenced-code-language
+MD040: false
+

vendor/go.opentelemetry.io/otel/CHANGELOG.md

+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
+
+This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## [1.9.0/0.0.3] - 2022-08-01
+
+### Added
+
+- Add support for Schema Files format 1.1.x (metric "split" transform) with the new `go.opentelemetry.io/otel/schema/v1.1` package. (#2999)
+- Add the `go.opentelemetry.io/otel/semconv/v1.11.0` package.
+  The package contains semantic conventions from the `v1.11.0` version of the OpenTelemetry specification. (#3009)
+- Add the `go.opentelemetry.io/otel/semconv/v1.12.0` package.
+  The package contains semantic conventions from the `v1.12.0` version of the OpenTelemetry specification. (#3010)
+- Add the `http.method` attribute to HTTP server metric from all `go.opentelemetry.io/otel/semconv/*` packages. (#3018)
+
+### Fixed
+
+- Invalid warning for context setup being deferred in `go.opentelemetry.io/otel/bridge/opentracing` package. (#3029)
+
+## [1.8.0/0.31.0] - 2022-07-08
+
+### Added
+
+- Add support for `opentracing.TextMap` format in the `Inject` and `Extract` methods
+of the `"go.opentelemetry.io/otel/bridge/opentracing".BridgeTracer` type. (#2911)
+
+### Changed
+
+- The `crosslink` make target has been updated to use the `go.opentelemetry.io/build-tools/crosslink` package. (#2886)
+- In the `go.opentelemetry.io/otel/sdk/instrumentation` package rename `Library` to `Scope` and alias `Library` as `Scope` (#2976)
+- Move metric no-op implementation form `nonrecording` to `metric` package. (#2866)
+
+### Removed
+
+- Support for go1.16. Support is now only for go1.17 and go1.18 (#2917)
+
+### Deprecated
+
+- The `Library` struct in the `go.opentelemetry.io/otel/sdk/instrumentation` package is deprecated.
+  Use the equivalent `Scope` struct instead. (#2977)
+- The `ReadOnlySpan.InstrumentationLibrary` method from the `go.opentelemetry.io/otel/sdk/trace` package is deprecated.
+  Use the equivalent `ReadOnlySpan.InstrumentationScope` method instead. (#2977)
+
+## [1.7.0/0.30.0] - 2022-04-28
+
+### Added
+
+- Add the `go.opentelemetry.io/otel/semconv/v1.8.0` package.
+  The package contains semantic conventions from the `v1.8.0` version of the OpenTelemetry specification. (#2763)
+- Add the `go.opentelemetry.io/otel/semconv/v1.9.0` package.
+  The package contains semantic conventions from the `v1.9.0` version of the OpenTelemetry specification. (#2792)
+- Add the `go.opentelemetry.io/otel/semconv/v1.10.0` package.
+  The package contains semantic conventions from the `v1.10.0` version of the OpenTelemetry specification. (#2842)
+- Added an in-memory exporter to metrictest to aid testing with a full SDK. (#2776)
+
+### Fixed
+
+- Globally delegated instruments are unwrapped before delegating asynchronous callbacks. (#2784)
+- Remove import of `testing` package in non-tests builds of the `go.opentelemetry.io/otel` package. (#2786)
+
+### Changed
+
+- The `WithLabelEncoder` option from the `go.opentelemetry.io/otel/exporters/stdout/stdoutmetric` package is renamed to `WithAttributeEncoder`. (#2790)
+- The `LabelFilterSelector` interface from `go.opentelemetry.io/otel/sdk/metric/processor/reducer` is renamed to `AttributeFilterSelector`.
+  The method included in the renamed interface also changed from `LabelFilterFor` to `AttributeFilterFor`. (#2790)
+- The `Metadata.Labels` method from the `go.opentelemetry.io/otel/sdk/metric/export` package is renamed to `Metadata.Attributes`.
+  Consequentially, the `Record` type from the same package also has had the embedded method renamed. (#2790)
+
+### Deprecated
+
+- The `Iterator.Label` method in the `go.opentelemetry.io/otel/attribute` package is deprecated.
+  Use the equivalent `Iterator.Attribute` method instead. (#2790)
+- The `Iterator.IndexedLabel` method in the `go.opentelemetry.io/otel/attribute` package is deprecated.
+  Use the equivalent `Iterator.IndexedAttribute` method instead. (#2790)
+- The `MergeIterator.Label` method in the `go.opentelemetry.io/otel/attribute` package is deprecated.
+  Use the equivalent `MergeIterator.Attribute` method instead. (#2790)
+
+### Removed
+
+- Removed the `Batch` type from the `go.opentelemetry.io/otel/sdk/metric/metrictest` package. (#2864)
+- Removed the `Measurement` type from the `go.opentelemetry.io/otel/sdk/metric/metrictest` package. (#2864)
+
+## [0.29.0] - 2022-04-11
+
+### Added
+
+- The metrics global package was added back into several test files. (#2764)
+- The `Meter` function is added back to the `go.opentelemetry.io/otel/metric/global` package.
+  This function is a convenience function equivalent to calling `global.MeterProvider().Meter(...)`. (#2750)
+
+### Removed
+
+- Removed module the `go.opentelemetry.io/otel/sdk/export/metric`.
+  Use the `go.opentelemetry.io/otel/sdk/metric` module instead. (#2720)
+
+### Changed
+
+- Don't panic anymore when setting a global MeterProvider to itself. (#2749)
+- Upgrade `go.opentelemetry.io/proto/otlp` in `go.opentelemetry.io/otel/exporters/otlp/otlpmetric` from `v0.12.1` to `v0.15.0`.
+  This replaces the use of the now deprecated `InstrumentationLibrary` and `InstrumentationLibraryMetrics` types and fields in the proto library with the equivalent `InstrumentationScope` and `ScopeMetrics`. (#2748)
+
+## [1.6.3] - 2022-04-07
+
+### Fixed
+
+- Allow non-comparable global `MeterProvider`, `TracerProvider`, and `TextMapPropagator` types to be set. (#2772, #2773)
+
+## [1.6.2] - 2022-04-06
+
+### Changed
+
+- Don't panic anymore when setting a global TracerProvider or TextMapPropagator to itself. (#2749)
+- Upgrade `go.opentelemetry.io/proto/otlp` in `go.opentelemetry.io/otel/exporters/otlp/otlptrace` from `v0.12.1` to `v0.15.0`.
+  This replaces the use of the now deprecated `InstrumentationLibrary` and `InstrumentationLibrarySpans` types and fields in the proto library with the equivalent `InstrumentationScope` and `ScopeSpans`. (#2748)
+
+## [1.6.1] - 2022-03-28
+
+### Fixed
+
+- The `go.opentelemetry.io/otel/schema/*` packages now use the correct schema URL for their `SchemaURL` constant.
+  Instead of using `"https://opentelemetry.io/schemas/v<version>"` they now use the correct URL without a `v` prefix, `"https://opentelemetry.io/schemas/<version>"`. (#2743, #2744)
+
+### Security
+
+- Upgrade `go.opentelemetry.io/proto/otlp` from `v0.12.0` to `v0.12.1`.
+  This includes an indirect upgrade of `github.com/grpc-ecosystem/grpc-gateway` which resolves [a vulnerability](https://nvd.nist.gov/vuln/detail/CVE-2019-11254) from `gopkg.in/yaml.v2` in version `v2.2.3`. (#2724, #2728)
+
+## [1.6.0/0.28.0] - 2022-03-23
+
+### ⚠️ Notice ⚠️
+
+This update is a breaking change of the unstable Metrics API.
+Code instrumented with the `go.opentelemetry.io/otel/metric` will need to be modified.
+
+### Added
+
+- Add metrics exponential histogram support.
+  New mapping functions have been made available in `sdk/metric/aggregator/exponential/mapping` for other OpenTelemetry projects to take dependencies on. (#2502)
+- Add Go 1.18 to our compatibility tests. (#2679)
+- Allow configuring the Sampler with the `OTEL_TRACES_SAMPLER` and `OTEL_TRACES_SAMPLER_ARG` environment variables. (#2305, #2517)
+- Add the `metric/global` for obtaining and setting the global `MeterProvider`. (#2660)
+
+### Changed
+
+- The metrics API has been significantly changed to match the revised OpenTelemetry specification.
+  High-level changes include:
+
+  - Synchronous and asynchronous instruments are now handled by independent `InstrumentProvider`s.
+    These `InstrumentProvider`s are managed with a `Meter`.
+  - Synchronous and asynchronous instruments are grouped into their own packages based on value types.
+  - Asynchronous callbacks can now be registered with a `Meter`.
+
+  Be sure to check out the metric module documentation for more information on how to use the revised API. (#2587, #2660)
+
+### Fixed
+
+- Fallback to general attribute limits when span specific ones are not set in the environment. (#2675, #2677)
+
+## [1.5.0] - 2022-03-16
+
+### Added
+
+- Log the Exporters configuration in the TracerProviders message. (#2578)
+- Added support to configure the span limits with environment variables.
+  The following environment variables are supported. (#2606, #2637)
+  - `OTEL_SPAN_ATTRIBUTE_VALUE_LENGTH_LIMIT`
+  - `OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT`
+  - `OTEL_SPAN_EVENT_COUNT_LIMIT`
+  - `OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT`
+  - `OTEL_SPAN_LINK_COUNT_LIMIT`
+  - `OTEL_LINK_ATTRIBUTE_COUNT_LIMIT`
+  
+  If the provided environment variables are invalid (negative), the default values would be used.
+- Rename the `gc` runtime name to `go` (#2560)
+- Add resource container ID detection. (#2418)
+- Add span attribute value length limit.
+  The new `AttributeValueLengthLimit` field is added to the `"go.opentelemetry.io/otel/sdk/trace".SpanLimits` type to configure this limit for a `TracerProvider`.
+  The default limit for this resource is "unlimited". (#2637)
+- Add the `WithRawSpanLimits` option to `go.opentelemetry.io/otel/sdk/trace`.
+  This option replaces the `WithSpanLimits` option.
+  Zero or negative values will not be changed to the default value like `WithSpanLimits` does.
+  Setting a limit to zero will effectively disable the related resource it limits and setting to a negative value will mean that resource is unlimited.
+  Consequentially, limits should be constructed using `NewSpanLimits` and updated accordingly. (#2637)
+
+### Changed
+
+- Drop oldest tracestate `Member` when capacity is reached. (#2592)
+- Add event and link drop counts to the exported data from the `oltptrace` exporter. (#2601)
+- Unify path cleaning functionally in the `otlpmetric` and `otlptrace` configuration. (#2639)
+- Change the debug message from the `sdk/trace.BatchSpanProcessor` to reflect the count is cumulative. (#2640)
+- Introduce new internal `envconfig` package for OTLP exporters. (#2608)
+- If `http.Request.Host` is empty, fall back to use `URL.Host` when populating `http.host` in the `semconv` packages. (#2661)
+
+### Fixed
+
+- Remove the OTLP trace exporter limit of SpanEvents when exporting. (#2616)
+- Default to port `4318` instead of `4317` for the `otlpmetrichttp` and `otlptracehttp` client. (#2614, #2625)
+- Unlimited span limits are now supported (negative values). (#2636, #2637)
+
+### Deprecated
+
+- Deprecated `"go.opentelemetry.io/otel/sdk/trace".WithSpanLimits`.
+  Use `WithRawSpanLimits` instead.
+  That option allows setting unlimited and zero limits, this option does not.
+  This option will be kept until the next major version incremented release. (#2637)
+
+## [1.4.1] - 2022-02-16
+
+### Fixed
+
+- Fix race condition in reading the dropped spans number for the `BatchSpanProcessor`. (#2615)
+
+## [1.4.0] - 2022-02-11
+
+### Added
+
+- Use `OTEL_EXPORTER_ZIPKIN_ENDPOINT` environment variable to specify zipkin collector endpoint. (#2490)
+- Log the configuration of `TracerProvider`s, and `Tracer`s for debugging.
+  To enable use a logger with Verbosity (V level) `>=1`. (#2500)
+- Added support to configure the batch span-processor with environment variables.
+  The following environment variables are used. (#2515)
+  - `OTEL_BSP_SCHEDULE_DELAY`
+  - `OTEL_BSP_EXPORT_TIMEOUT`
+  - `OTEL_BSP_MAX_QUEUE_SIZE`.
+  - `OTEL_BSP_MAX_EXPORT_BATCH_SIZE`
+
+### Changed
+
+- Zipkin exporter exports `Resource` attributes in the `Tags` field. (#2589)
+
+### Deprecated
+
+- Deprecate module the `go.opentelemetry.io/otel/sdk/export/metric`.
+  Use the `go.opentelemetry.io/otel/sdk/metric` module instead. (#2382)
+- Deprecate `"go.opentelemetry.io/otel/sdk/metric".AtomicFieldOffsets`. (#2445)
+
+### Fixed
+
+- Fixed the instrument kind for noop async instruments to correctly report an implementation. (#2461)
+- Fix UDP packets overflowing with Jaeger payloads. (#2489, #2512)
+- Change the `otlpmetric.Client` interface's `UploadMetrics` method to accept a single `ResourceMetrics` instead of a slice of them. (#2491)
+- Specify explicit buckets in Prometheus example, fixing issue where example only has `+inf` bucket. (#2419, #2493)
+- W3C baggage will now decode urlescaped values. (#2529)
+- Baggage members are now only validated once, when calling `NewMember` and not also when adding it to the baggage itself. (#2522)
+- The order attributes are dropped from spans in the `go.opentelemetry.io/otel/sdk/trace` package when capacity is reached is fixed to be in compliance with the OpenTelemetry specification.
+  Instead of dropping the least-recently-used attribute, the last added attribute is dropped.
+  This drop order still only applies to attributes with unique keys not already contained in the span.
+  If an attribute is added with a key already contained in the span, that attribute is updated to the new value being added. (#2576)
+
+### Removed
+
+- Updated `go.opentelemetry.io/proto/otlp` from `v0.11.0` to `v0.12.0`. This version removes a number of deprecated methods. (#2546)
+  - [`Metric.GetIntGauge()`](https://pkg.go.dev/go.opentelemetry.io/proto/otlp@v0.11.0/metrics/v1#Metric.GetIntGauge)
+  - [`Metric.GetIntHistogram()`](https://pkg.go.dev/go.opentelemetry.io/proto/otlp@v0.11.0/metrics/v1#Metric.GetIntHistogram)
+  - [`Metric.GetIntSum()`](https://pkg.go.dev/go.opentelemetry.io/proto/otlp@v0.11.0/metrics/v1#Metric.GetIntSum)
+
+## [1.3.0] - 2021-12-10
+
+### ⚠️ Notice ⚠️
+
+We have updated the project minimum supported Go version to 1.16
+
+### Added
+
+- Added an internal Logger.
+  This can be used by the SDK and API to provide users with feedback of the internal state.
+  To enable verbose logs configure the logger which will print V(1) logs. For debugging information configure to print V(5) logs. (#2343)
+- Add the `WithRetry` `Option` and the `RetryConfig` type to the `go.opentelemetry.io/otel/exporter/otel/otlpmetric/otlpmetrichttp` package to specify retry behavior consistently. (#2425)
+- Add `SpanStatusFromHTTPStatusCodeAndSpanKind` to all `semconv` packages to return a span status code similar to `SpanStatusFromHTTPStatusCode`, but exclude `4XX` HTTP errors as span errors if the span is of server kind. (#2296)
+
+### Changed
+
+- The `"go.opentelemetry.io/otel/exporter/otel/otlptrace/otlptracegrpc".Client` now uses the underlying gRPC `ClientConn` to handle name resolution, TCP connection establishment (with retries and backoff) and TLS handshakes, and handling errors on established connections by re-resolving the name and reconnecting. (#2329)
+- The `"go.opentelemetry.io/otel/exporter/otel/otlpmetric/otlpmetricgrpc".Client` now uses the underlying gRPC `ClientConn` to handle name resolution, TCP connection establishment (with retries and backoff) and TLS handshakes, and handling errors on established connections by re-resolving the name and reconnecting. (#2425)
+- The `"go.opentelemetry.io/otel/exporter/otel/otlpmetric/otlpmetricgrpc".RetrySettings` type is renamed to `RetryConfig`. (#2425)
+- The `go.opentelemetry.io/otel/exporter/otel/*` gRPC exporters now default to using the host's root CA set if none are provided by the user and `WithInsecure` is not specified. (#2432)
+- Change `resource.Default` to be evaluated the first time it is called, rather than on import. This allows the caller the option to update `OTEL_RESOURCE_ATTRIBUTES` first, such as with `os.Setenv`. (#2371)
+
+### Fixed
+
+- The `go.opentelemetry.io/otel/exporter/otel/*` exporters are updated to handle per-signal and universal endpoints according to the OpenTelemetry specification.
+  Any per-signal endpoint set via an `OTEL_EXPORTER_OTLP_<signal>_ENDPOINT` environment variable is now used without modification of the path.
+  When `OTEL_EXPORTER_OTLP_ENDPOINT` is set, if it contains a path, that path is used as a base path which per-signal paths are appended to. (#2433)
+- Basic metric controller updated to use sync.Map to avoid blocking calls (#2381)
+- The `go.opentelemetry.io/otel/exporter/jaeger` correctly sets the `otel.status_code` value to be a string of `ERROR` or `OK` instead of an integer code. (#2439, #2440)
+
+### Deprecated
+
+- Deprecated the `"go.opentelemetry.io/otel/exporter/otel/otlpmetric/otlpmetrichttp".WithMaxAttempts` `Option`, use the new `WithRetry` `Option` instead. (#2425)
+- Deprecated the `"go.opentelemetry.io/otel/exporter/otel/otlpmetric/otlpmetrichttp".WithBackoff` `Option`, use the new `WithRetry` `Option` instead. (#2425)
+
+### Removed
+
+- Remove the metric Processor's ability to convert cumulative to delta aggregation temporality. (#2350)
+- Remove the metric Bound Instruments interface and implementations. (#2399)
+- Remove the metric MinMaxSumCount kind aggregation and the corresponding OTLP export path. (#2423)
+- Metric SDK removes the "exact" aggregator for histogram instruments, as it performed a non-standard aggregation for OTLP export (creating repeated Gauge points) and worked its way into a number of confusing examples. (#2348)
+
+## [1.2.0] - 2021-11-12
+
+### Changed
+
+- Metric SDK `export.ExportKind`, `export.ExportKindSelector` types have been renamed to `aggregation.Temporality` and `aggregation.TemporalitySelector` respectively to keep in line with current specification and protocol along with built-in selectors (e.g., `aggregation.CumulativeTemporalitySelector`, ...). (#2274)
+- The Metric `Exporter` interface now requires a `TemporalitySelector` method instead of an `ExportKindSelector`. (#2274)
+- Metrics API cleanup. The `metric/sdkapi` package has been created to relocate the API-to-SDK interface:
+  - The following interface types simply moved from `metric` to `metric/sdkapi`: `Descriptor`, `MeterImpl`, `InstrumentImpl`, `SyncImpl`, `BoundSyncImpl`, `AsyncImpl`, `AsyncRunner`, `AsyncSingleRunner`, and `AsyncBatchRunner`
+  - The following struct types moved and are replaced with type aliases, since they are exposed to the user: `Observation`, `Measurement`.
+  - The No-op implementations of sync and async instruments are no longer exported, new functions `sdkapi.NewNoopAsyncInstrument()` and `sdkapi.NewNoopSyncInstrument()` are provided instead. (#2271)
+- Update the SDK `BatchSpanProcessor` to export all queued spans when `ForceFlush` is called. (#2080, #2335)
+
+### Added
+
+- Add the `"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc".WithGRPCConn` option so the exporter can reuse an existing gRPC connection. (#2002)
+- Added a new `schema` module to help parse Schema Files in OTEP 0152 format. (#2267)
+- Added a new `MapCarrier` to the `go.opentelemetry.io/otel/propagation` package to hold propagated cross-cutting concerns as a `map[string]string` held in memory. (#2334)
+
+## [1.1.0] - 2021-10-27
+
+### Added
+
+- Add the `"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc".WithGRPCConn` option so the exporter can reuse an existing gRPC connection. (#2002)
+- Add the `go.opentelemetry.io/otel/semconv/v1.7.0` package.
+  The package contains semantic conventions from the `v1.7.0` version of the OpenTelemetry specification. (#2320)
+- Add the `go.opentelemetry.io/otel/semconv/v1.6.1` package.
+  The package contains semantic conventions from the `v1.6.1` version of the OpenTelemetry specification. (#2321)
+- Add the `go.opentelemetry.io/otel/semconv/v1.5.0` package.
+  The package contains semantic conventions from the `v1.5.0` version of the OpenTelemetry specification. (#2322)
+  - When upgrading from the `semconv/v1.4.0` package note the following name changes:
+    - `K8SReplicasetUIDKey` -> `K8SReplicaSetUIDKey`
+    - `K8SReplicasetNameKey` -> `K8SReplicaSetNameKey`
+    - `K8SStatefulsetUIDKey` -> `K8SStatefulSetUIDKey`
+    - `k8SStatefulsetNameKey` -> `K8SStatefulSetNameKey`
+    - `K8SDaemonsetUIDKey` -> `K8SDaemonSetUIDKey`
+    - `K8SDaemonsetNameKey` -> `K8SDaemonSetNameKey`
+
+### Changed
+
+- Links added to a span will be dropped by the SDK if they contain an invalid span context (#2275).
+
+### Fixed
+
+- The `"go.opentelemetry.io/otel/semconv/v1.4.0".HTTPServerAttributesFromHTTPRequest` now correctly only sets the HTTP client IP attribute even if the connection was routed with proxies and there are multiple addresses in the `X-Forwarded-For` header. (#2282, #2284)
+- The `"go.opentelemetry.io/otel/semconv/v1.4.0".NetAttributesFromHTTPRequest` function correctly handles IPv6 addresses as IP addresses and sets the correct net peer IP instead of the net peer hostname attribute. (#2283, #2285)
+- The simple span processor shutdown method deterministically returns the exporter error status if it simultaneously finishes when the deadline is reached. (#2290, #2289)
+
+## [1.0.1] - 2021-10-01
+
+### Fixed
+
+- json stdout exporter no longer crashes due to concurrency bug. (#2265)
+
+## [Metrics 0.24.0] - 2021-10-01
+
+### Changed
+
+- NoopMeterProvider is now private and NewNoopMeterProvider must be used to obtain a noopMeterProvider. (#2237)
+- The Metric SDK `Export()` function takes a new two-level reader interface for iterating over results one instrumentation library at a time. (#2197)
+  - The former `"go.opentelemetry.io/otel/sdk/export/metric".CheckpointSet` is renamed `Reader`.
+  - The new interface is named `"go.opentelemetry.io/otel/sdk/export/metric".InstrumentationLibraryReader`.
+
+## [1.0.0] - 2021-09-20
+
+This is the first stable release for the project.
+This release includes an API and SDK for the tracing signal that will comply with the stability guarantees defined by the projects [versioning policy](./VERSIONING.md).
+
+### Added
+
+- OTLP trace exporter now sets the `SchemaURL` field in the exported telemetry if the Tracer has `WithSchemaURL` option. (#2242)
+
+### Fixed
+
+- Slice-valued attributes can correctly be used as map keys. (#2223)
+
+### Removed
+
+- Removed the `"go.opentelemetry.io/otel/exporters/zipkin".WithSDKOptions` function. (#2248)
+- Removed the deprecated package `go.opentelemetry.io/otel/oteltest`. (#2234)
+- Removed the deprecated package `go.opentelemetry.io/otel/bridge/opencensus/utils`. (#2233)
+- Removed deprecated functions, types, and methods from `go.opentelemetry.io/otel/attribute` package.
+  Use the typed functions and methods added to the package instead. (#2235)
+  - The `Key.Array` method is removed.
+  - The `Array` function is removed.
+  - The `Any` function is removed.
+  - The `ArrayValue` function is removed.
+  - The `AsArray` function is removed.
+
+## [1.0.0-RC3] - 2021-09-02
+
+### Added
+
+- Added `ErrorHandlerFunc` to use a function as an `"go.opentelemetry.io/otel".ErrorHandler`. (#2149)
+- Added `"go.opentelemetry.io/otel/trace".WithStackTrace` option to add a stack trace when using `span.RecordError` or when panic is handled in `span.End`. (#2163)
+- Added typed slice attribute types and functionality to the `go.opentelemetry.io/otel/attribute` package to replace the existing array type and functions. (#2162)
+  - `BoolSlice`, `IntSlice`, `Int64Slice`, `Float64Slice`, and `StringSlice` replace the use of the `Array` function in the package.
+- Added the `go.opentelemetry.io/otel/example/fib` example package.
+  Included is an example application that computes Fibonacci numbers. (#2203)
+
+### Changed
+
+- Metric instruments have been renamed to match the (feature-frozen) metric API specification:
+  - ValueRecorder becomes Histogram
+  - ValueObserver becomes Gauge
+  - SumObserver becomes CounterObserver
+  - UpDownSumObserver becomes UpDownCounterObserver
+  The API exported from this project is still considered experimental. (#2202)
+- Metric SDK/API implementation type `InstrumentKind` moves into `sdkapi` sub-package. (#2091)
+- The Metrics SDK export record no longer contains a Resource pointer, the SDK `"go.opentelemetry.io/otel/sdk/trace/export/metric".Exporter.Export()` function for push-based exporters now takes a single Resource argument, pull-based exporters use `"go.opentelemetry.io/otel/sdk/metric/controller/basic".Controller.Resource()`. (#2120)
+- The JSON output of the `go.opentelemetry.io/otel/exporters/stdout/stdouttrace` is harmonized now such that the output is "plain" JSON objects after each other of the form `{ ... } { ... } { ... }`. Earlier the JSON objects describing a span were wrapped in a slice for each `Exporter.ExportSpans` call, like `[ { ... } ][ { ... } { ... } ]`. Outputting JSON object directly after each other is consistent with JSON loggers, and a bit easier to parse and read. (#2196)
+- Update the `NewTracerConfig`, `NewSpanStartConfig`, `NewSpanEndConfig`, and `NewEventConfig` function in the `go.opentelemetry.io/otel/trace` package to return their respective configurations as structs instead of pointers to the struct. (#2212)
+
+### Deprecated
+
+- The `go.opentelemetry.io/otel/bridge/opencensus/utils` package is deprecated.
+  All functionality from this package now exists in the `go.opentelemetry.io/otel/bridge/opencensus` package.
+  The functions from that package should be used instead. (#2166)
+- The `"go.opentelemetry.io/otel/attribute".Array` function and the related `ARRAY` value type is deprecated.
+  Use the typed `*Slice` functions and types added to the package instead. (#2162)
+- The `"go.opentelemetry.io/otel/attribute".Any` function is deprecated.
+  Use the typed functions instead. (#2181)
+- The `go.opentelemetry.io/otel/oteltest` package is deprecated.
+  The `"go.opentelemetry.io/otel/sdk/trace/tracetest".SpanRecorder` can be registered with the default SDK (`go.opentelemetry.io/otel/sdk/trace`) as a `SpanProcessor` and used as a replacement for this deprecated package. (#2188)
+
+### Removed
+
+- Removed metrics test package `go.opentelemetry.io/otel/sdk/export/metric/metrictest`. (#2105)
+
+### Fixed
+
+- The `fromEnv` detector no longer throws an error when `OTEL_RESOURCE_ATTRIBUTES` environment variable is not set or empty. (#2138)
+- Setting the global `ErrorHandler` with `"go.opentelemetry.io/otel".SetErrorHandler` multiple times is now supported. (#2160, #2140)
+- The `"go.opentelemetry.io/otel/attribute".Any` function now supports `int32` values. (#2169)
+- Multiple calls to `"go.opentelemetry.io/otel/sdk/metric/controller/basic".WithResource()` are handled correctly, and when no resources are provided `"go.opentelemetry.io/otel/sdk/resource".Default()` is used. (#2120)
+- The `WithoutTimestamps` option for the `go.opentelemetry.io/otel/exporters/stdout/stdouttrace` exporter causes the exporter to correctly ommit timestamps. (#2195)
+- Fixed typos in resources.go. (#2201)
+
+## [1.0.0-RC2] - 2021-07-26
+
+### Added
+
+- Added `WithOSDescription` resource configuration option to set OS (Operating System) description resource attribute (`os.description`). (#1840)
+- Added `WithOS` resource configuration option to set all OS (Operating System) resource attributes at once. (#1840)
+- Added the `WithRetry` option to the `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp` package.
+  This option is a replacement for the removed `WithMaxAttempts` and `WithBackoff` options. (#2095)
+- Added API `LinkFromContext` to return Link which encapsulates SpanContext from provided context and also encapsulates attributes. (#2115)
+- Added a new `Link` type under the SDK `otel/sdk/trace` package that counts the number of attributes that were dropped for surpassing the `AttributePerLinkCountLimit` configured in the Span's `SpanLimits`.
+  This new type replaces the equal-named API `Link` type found in the `otel/trace` package for most usages within the SDK.
+  For example, instances of this type are now returned by the `Links()` function of `ReadOnlySpan`s provided in places like the `OnEnd` function of `SpanProcessor` implementations. (#2118)
+- Added the `SpanRecorder` type to the `go.opentelemetry.io/otel/skd/trace/tracetest` package.
+  This type can be used with the default SDK as a `SpanProcessor` during testing. (#2132)
+
+### Changed
+
+- The `SpanModels` function is now exported from the `go.opentelemetry.io/otel/exporters/zipkin` package to convert OpenTelemetry spans into Zipkin model spans. (#2027)
+- Rename the `"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc".RetrySettings` to `RetryConfig`. (#2095)
+
+### Deprecated
+
+- The `TextMapCarrier` and `TextMapPropagator` from the `go.opentelemetry.io/otel/oteltest` package and their associated creation functions (`TextMapCarrier`, `NewTextMapPropagator`) are deprecated. (#2114)
+- The `Harness` type from the `go.opentelemetry.io/otel/oteltest` package and its associated creation function, `NewHarness` are deprecated and will be removed in the next release. (#2123)
+- The `TraceStateFromKeyValues` function from the `go.opentelemetry.io/otel/oteltest` package is deprecated.
+  Use the `trace.ParseTraceState` function instead. (#2122)
+
+### Removed
+
+- Removed the deprecated package `go.opentelemetry.io/otel/exporters/trace/jaeger`. (#2020)
+- Removed the deprecated package `go.opentelemetry.io/otel/exporters/trace/zipkin`. (#2020)
+- Removed the `"go.opentelemetry.io/otel/sdk/resource".WithBuiltinDetectors` function.
+  The explicit `With*` options for every built-in detector should be used instead. (#2026 #2097)
+- Removed the `WithMaxAttempts` and `WithBackoff` options from the `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp` package.
+  The retry logic of the package has been updated to match the `otlptracegrpc` package and accordingly a `WithRetry` option is added that should be used instead. (#2095)
+- Removed `DroppedAttributeCount` field from `otel/trace.Link` struct. (#2118)
+
+### Fixed
+
+- When using WithNewRoot, don't use the parent context for making sampling decisions. (#2032)
+- `oteltest.Tracer` now creates a valid `SpanContext` when using `WithNewRoot`. (#2073)
+- OS type detector now sets the correct `dragonflybsd` value for DragonFly BSD. (#2092)
+- The OTel span status is correctly transformed into the OTLP status in the `go.opentelemetry.io/otel/exporters/otlp/otlptrace` package.
+  This fix will by default set the status to `Unset` if it is not explicitly set to `Ok` or `Error`. (#2099 #2102)
+- The `Inject` method for the `"go.opentelemetry.io/otel/propagation".TraceContext` type no longer injects empty `tracestate` values. (#2108)
+- Use `6831` as default Jaeger agent port instead of `6832`. (#2131)
+
+## [Experimental Metrics v0.22.0] - 2021-07-19
+
+### Added
+
+- Adds HTTP support for OTLP metrics exporter. (#2022)
+
+### Removed
+
+- Removed the deprecated package `go.opentelemetry.io/otel/exporters/metric/prometheus`. (#2020)
+
+## [1.0.0-RC1] / 0.21.0 - 2021-06-18
+
+With this release we are introducing a split in module versions.  The tracing API and SDK are entering the `v1.0.0` Release Candidate phase with `v1.0.0-RC1`
+while the experimental metrics API and SDK continue with `v0.x` releases at `v0.21.0`.  Modules at major version 1 or greater will not depend on modules
+with major version 0.
+
+### Added
+
+- Adds `otlpgrpc.WithRetry`option for configuring the retry policy for transient errors on the otlp/gRPC exporter. (#1832)
+  - The following status codes are defined as transient errors:
+      | gRPC Status Code | Description |
+      | ---------------- | ----------- |
+      | 1  | Cancelled |
+      | 4  | Deadline Exceeded |
+      | 8  | Resource Exhausted |
+      | 10 | Aborted |
+      | 10 | Out of Range |
+      | 14 | Unavailable |
+      | 15 | Data Loss |
+- Added `Status` type to the `go.opentelemetry.io/otel/sdk/trace` package to represent the status of a span. (#1874)
+- Added `SpanStub` type and its associated functions to the `go.opentelemetry.io/otel/sdk/trace/tracetest` package.
+  This type can be used as a testing replacement for the `SpanSnapshot` that was removed from the `go.opentelemetry.io/otel/sdk/trace` package. (#1873)
+- Adds support for scheme in `OTEL_EXPORTER_OTLP_ENDPOINT` according to the spec. (#1886)
+- Adds `trace.WithSchemaURL` option for configuring the tracer with a Schema URL. (#1889)
+- Added an example of using OpenTelemetry Go as a trace context forwarder. (#1912)
+- `ParseTraceState` is added to the `go.opentelemetry.io/otel/trace` package.
+  It can be used to decode a `TraceState` from a `tracestate` header string value. (#1937)
+- Added `Len` method to the `TraceState` type in the `go.opentelemetry.io/otel/trace` package.
+  This method returns the number of list-members the `TraceState` holds. (#1937)
+- Creates package `go.opentelemetry.io/otel/exporters/otlp/otlptrace` that defines a trace exporter that uses a `otlptrace.Client` to send data.
+  Creates package `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc` implementing a gRPC `otlptrace.Client` and offers convenience functions, `NewExportPipeline` and `InstallNewPipeline`, to setup and install a `otlptrace.Exporter` in tracing .(#1922)
+- Added `Baggage`, `Member`, and `Property` types to the `go.opentelemetry.io/otel/baggage` package along with their related functions. (#1967)
+- Added `ContextWithBaggage`, `ContextWithoutBaggage`, and `FromContext` functions to the `go.opentelemetry.io/otel/baggage` package.
+  These functions replace the `Set`, `Value`, `ContextWithValue`, `ContextWithoutValue`, and `ContextWithEmpty` functions from that package and directly work with the new `Baggage` type. (#1967)
+- The `OTEL_SERVICE_NAME` environment variable is the preferred source for `service.name`, used by the environment resource detector if a service name is present both there and in `OTEL_RESOURCE_ATTRIBUTES`. (#1969)
+- Creates package `go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp` implementing an HTTP `otlptrace.Client` and offers convenience functions, `NewExportPipeline` and `InstallNewPipeline`, to setup and install a `otlptrace.Exporter` in tracing. (#1963)
+- Changes `go.opentelemetry.io/otel/sdk/resource.NewWithAttributes` to require a schema URL. The old function is still available as `resource.NewSchemaless`. This is a breaking change. (#1938)
+- Several builtin resource detectors now correctly populate the schema URL. (#1938)
+- Creates package `go.opentelemetry.io/otel/exporters/otlp/otlpmetric` that defines a metrics exporter that uses a `otlpmetric.Client` to send data.
+- Creates package `go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc` implementing a gRPC `otlpmetric.Client` and offers convenience functions, `New` and `NewUnstarted`, to create an `otlpmetric.Exporter`.(#1991)
+- Added `go.opentelemetry.io/otel/exporters/stdout/stdouttrace` exporter. (#2005)
+- Added `go.opentelemetry.io/otel/exporters/stdout/stdoutmetric` exporter. (#2005)
+- Added a `TracerProvider()` method to the `"go.opentelemetry.io/otel/trace".Span` interface. This can be used to obtain a `TracerProvider` from a given span that utilizes the same trace processing pipeline.  (#2009)
+
+### Changed
+
+- Make `NewSplitDriver` from `go.opentelemetry.io/otel/exporters/otlp` take variadic arguments instead of a `SplitConfig` item.
+  `NewSplitDriver` now automatically implements an internal `noopDriver` for `SplitConfig` fields that are not initialized. (#1798)
+- `resource.New()` now creates a Resource without builtin detectors. Previous behavior is now achieved by using `WithBuiltinDetectors` Option. (#1810)
+- Move the `Event` type from the `go.opentelemetry.io/otel` package to the `go.opentelemetry.io/otel/sdk/trace` package. (#1846)
+- CI builds validate against last two versions of Go, dropping 1.14 and adding 1.16. (#1865)
+- BatchSpanProcessor now report export failures when calling `ForceFlush()` method. (#1860)
+- `Set.Encoded(Encoder)` no longer caches the result of an encoding. (#1855)
+- Renamed `CloudZoneKey` to `CloudAvailabilityZoneKey` in Resource semantic conventions according to spec. (#1871)
+- The `StatusCode` and `StatusMessage` methods of the `ReadOnlySpan` interface and the `Span` produced by the `go.opentelemetry.io/otel/sdk/trace` package have been replaced with a single `Status` method.
+  This method returns the status of a span using the new `Status` type. (#1874)
+- Updated `ExportSpans` method of the`SpanExporter` interface type to accept `ReadOnlySpan`s instead of the removed `SpanSnapshot`.
+  This brings the export interface into compliance with the specification in that it now accepts an explicitly immutable type instead of just an implied one. (#1873)
+- Unembed `SpanContext` in `Link`. (#1877)
+- Generate Semantic conventions from the specification YAML. (#1891)
+- Spans created by the global `Tracer` obtained from `go.opentelemetry.io/otel`, prior to a functioning `TracerProvider` being set, now propagate the span context from their parent if one exists. (#1901)
+- The `"go.opentelemetry.io/otel".Tracer` function now accepts tracer options. (#1902)
+- Move the `go.opentelemetry.io/otel/unit` package to `go.opentelemetry.io/otel/metric/unit`. (#1903)
+- Changed `go.opentelemetry.io/otel/trace.TracerConfig` to conform to the [Contributing guidelines](CONTRIBUTING.md#config.) (#1921)
+- Changed `go.opentelemetry.io/otel/trace.SpanConfig` to conform to the [Contributing guidelines](CONTRIBUTING.md#config). (#1921)
+- Changed `span.End()` now only accepts Options that are allowed at `End()`. (#1921)
+- Changed `go.opentelemetry.io/otel/metric.InstrumentConfig` to conform to the [Contributing guidelines](CONTRIBUTING.md#config). (#1921)
+- Changed `go.opentelemetry.io/otel/metric.MeterConfig` to conform to the [Contributing guidelines](CONTRIBUTING.md#config). (#1921)
+- Refactored option types according to the contribution style guide. (#1882)
+- Move the `go.opentelemetry.io/otel/trace.TraceStateFromKeyValues` function to the `go.opentelemetry.io/otel/oteltest` package.
+  This function is preserved for testing purposes where it may be useful to create a `TraceState` from `attribute.KeyValue`s, but it is not intended for production use.
+  The new `ParseTraceState` function should be used to create a `TraceState`. (#1931)
+- Updated `MarshalJSON` method of the `go.opentelemetry.io/otel/trace.TraceState` type to marshal the type into the string representation of the `TraceState`. (#1931)
+- The `TraceState.Delete` method from the `go.opentelemetry.io/otel/trace` package no longer returns an error in addition to a `TraceState`. (#1931)
+- Updated `Get` method of the `TraceState` type from the `go.opentelemetry.io/otel/trace` package to accept a `string` instead of an `attribute.Key` type. (#1931)
+- Updated `Insert` method of the `TraceState` type from the `go.opentelemetry.io/otel/trace` package to accept a pair of `string`s instead of an `attribute.KeyValue` type. (#1931)
+- Updated `Delete` method of the `TraceState` type from the `go.opentelemetry.io/otel/trace` package to accept a `string` instead of an `attribute.Key` type. (#1931)
+- Renamed `NewExporter` to `New` in the `go.opentelemetry.io/otel/exporters/stdout` package. (#1985)
+- Renamed `NewExporter` to `New` in the `go.opentelemetry.io/otel/exporters/metric/prometheus` package. (#1985)
+- Renamed `NewExporter` to `New` in the `go.opentelemetry.io/otel/exporters/trace/jaeger` package. (#1985)
+- Renamed `NewExporter` to `New` in the `go.opentelemetry.io/otel/exporters/trace/zipkin` package. (#1985)
+- Renamed `NewExporter` to `New` in the `go.opentelemetry.io/otel/exporters/otlp` package. (#1985)
+- Renamed `NewUnstartedExporter` to `NewUnstarted` in the `go.opentelemetry.io/otel/exporters/otlp` package. (#1985)
+- The `go.opentelemetry.io/otel/semconv` package has been moved to `go.opentelemetry.io/otel/semconv/v1.4.0` to allow for multiple [telemetry schema](https://github.com/open-telemetry/oteps/blob/main/text/0152-telemetry-schemas.md) versions to be used concurrently. (#1987)
+- Metrics test helpers in `go.opentelemetry.io/otel/oteltest` have been moved to `go.opentelemetry.io/otel/metric/metrictest`. (#1988)
+
+### Deprecated
+
+- The `go.opentelemetry.io/otel/exporters/metric/prometheus` is deprecated, use `go.opentelemetry.io/otel/exporters/prometheus` instead. (#1993)
+- The `go.opentelemetry.io/otel/exporters/trace/jaeger` is deprecated, use `go.opentelemetry.io/otel/exporters/jaeger` instead. (#1993)
+- The `go.opentelemetry.io/otel/exporters/trace/zipkin` is deprecated, use `go.opentelemetry.io/otel/exporters/zipkin` instead. (#1993)
+
+### Removed
+
+- Removed `resource.WithoutBuiltin()`. Use `resource.New()`. (#1810)
+- Unexported types `resource.FromEnv`, `resource.Host`, and `resource.TelemetrySDK`, Use the corresponding `With*()` to use individually. (#1810)
+- Removed the `Tracer` and `IsRecording` method from the `ReadOnlySpan` in the `go.opentelemetry.io/otel/sdk/trace`.
+  The `Tracer` method is not a required to be included in this interface and given the mutable nature of the tracer that is associated with a span, this method is not appropriate.
+  The `IsRecording` method returns if the span is recording or not.
+  A read-only span value does not need to know if updates to it will be recorded or not.
+  By definition, it cannot be updated so there is no point in communicating if an update is recorded. (#1873)
+- Removed the `SpanSnapshot` type from the `go.opentelemetry.io/otel/sdk/trace` package.
+  The use of this type has been replaced with the use of the explicitly immutable `ReadOnlySpan` type.
+  When a concrete representation of a read-only span is needed for testing, the newly added `SpanStub` in the `go.opentelemetry.io/otel/sdk/trace/tracetest` package should be used. (#1873)
+- Removed the `Tracer` method from the `Span` interface in the `go.opentelemetry.io/otel/trace` package.
+  Using the same tracer that created a span introduces the error where an instrumentation library's `Tracer` is used by other code instead of their own.
+  The `"go.opentelemetry.io/otel".Tracer` function or a `TracerProvider` should be used to acquire a library specific `Tracer` instead. (#1900)
+  - The `TracerProvider()` method on the `Span` interface may also be used to obtain a `TracerProvider` using the same trace processing pipeline. (#2009)
+- The `http.url` attribute generated by `HTTPClientAttributesFromHTTPRequest` will no longer include username or password information. (#1919)
+- Removed `IsEmpty` method of the `TraceState` type in the `go.opentelemetry.io/otel/trace` package in favor of using the added `TraceState.Len` method. (#1931)
+- Removed `Set`, `Value`, `ContextWithValue`, `ContextWithoutValue`, and `ContextWithEmpty` functions in the `go.opentelemetry.io/otel/baggage` package.
+  Handling of baggage is now done using the added `Baggage` type and related context functions (`ContextWithBaggage`, `ContextWithoutBaggage`, and `FromContext`) in that package. (#1967)
+- The `InstallNewPipeline` and `NewExportPipeline` creation functions in all the exporters (prometheus, otlp, stdout, jaeger, and zipkin) have been removed.
+  These functions were deemed premature attempts to provide convenience that did not achieve this aim. (#1985)
+- The `go.opentelemetry.io/otel/exporters/otlp` exporter has been removed.  Use `go.opentelemetry.io/otel/exporters/otlp/otlptrace` instead. (#1990)
+- The `go.opentelemetry.io/otel/exporters/stdout` exporter has been removed.  Use `go.opentelemetry.io/otel/exporters/stdout/stdouttrace` or `go.opentelemetry.io/otel/exporters/stdout/stdoutmetric` instead. (#2005)
+
+### Fixed
+
+- Only report errors from the `"go.opentelemetry.io/otel/sdk/resource".Environment` function when they are not `nil`. (#1850, #1851)
+- The `Shutdown` method of the simple `SpanProcessor` in the `go.opentelemetry.io/otel/sdk/trace` package now honors the context deadline or cancellation. (#1616, #1856)
+- BatchSpanProcessor now drops span batches that failed to be exported. (#1860)
+- Use `http://localhost:14268/api/traces` as default Jaeger collector endpoint instead of `http://localhost:14250`. (#1898)
+- Allow trailing and leading whitespace in the parsing of a `tracestate` header. (#1931)
+- Add logic to determine if the channel is closed to fix Jaeger exporter test panic with close closed channel. (#1870, #1973)
+- Avoid transport security when OTLP endpoint is a Unix socket. (#2001)
+
+### Security
+
+## [0.20.0] - 2021-04-23
+
+### Added
+
+- The OTLP exporter now has two new convenience functions, `NewExportPipeline` and `InstallNewPipeline`, setup and install the exporter in tracing and metrics pipelines. (#1373)
+- Adds semantic conventions for exceptions. (#1492)
+- Added Jaeger Environment variables: `OTEL_EXPORTER_JAEGER_AGENT_HOST`, `OTEL_EXPORTER_JAEGER_AGENT_PORT`
+  These environment variables can be used to override Jaeger agent hostname and port (#1752)
+- Option `ExportTimeout` was added to batch span processor. (#1755)
+- `trace.TraceFlags` is now a defined type over `byte` and `WithSampled(bool) TraceFlags` and `IsSampled() bool` methods have been added to it. (#1770)
+- The `Event` and `Link` struct types from the `go.opentelemetry.io/otel` package now include a `DroppedAttributeCount` field to record the number of attributes that were not recorded due to configured limits being reached. (#1771)
+- The Jaeger exporter now reports dropped attributes for a Span event in the exported log. (#1771)
+- Adds test to check BatchSpanProcessor ignores `OnEnd` and `ForceFlush` post `Shutdown`. (#1772)
+- Extract resource attributes from the `OTEL_RESOURCE_ATTRIBUTES` environment variable and merge them with the `resource.Default` resource as well as resources provided to the `TracerProvider` and metric `Controller`. (#1785)
+- Added `WithOSType` resource configuration option to set OS (Operating System) type resource attribute (`os.type`). (#1788)
+- Added `WithProcess*` resource configuration options to set Process resource attributes. (#1788)
+  - `process.pid`
+  - `process.executable.name`
+  - `process.executable.path`
+  - `process.command_args`
+  - `process.owner`
+  - `process.runtime.name`
+  - `process.runtime.version`
+  - `process.runtime.description`
+- Adds `k8s.node.name` and `k8s.node.uid` attribute keys to the `semconv` package. (#1789)
+- Added support for configuring OTLP/HTTP and OTLP/gRPC Endpoints, TLS Certificates, Headers, Compression and Timeout via Environment Variables. (#1758, #1769 and #1811)
+  - `OTEL_EXPORTER_OTLP_ENDPOINT`
+  - `OTEL_EXPORTER_OTLP_TRACES_ENDPOINT`
+  - `OTEL_EXPORTER_OTLP_METRICS_ENDPOINT`
+  - `OTEL_EXPORTER_OTLP_HEADERS`
+  - `OTEL_EXPORTER_OTLP_TRACES_HEADERS`
+  - `OTEL_EXPORTER_OTLP_METRICS_HEADERS`
+  - `OTEL_EXPORTER_OTLP_COMPRESSION`
+  - `OTEL_EXPORTER_OTLP_TRACES_COMPRESSION`
+  - `OTEL_EXPORTER_OTLP_METRICS_COMPRESSION`
+  - `OTEL_EXPORTER_OTLP_TIMEOUT`
+  - `OTEL_EXPORTER_OTLP_TRACES_TIMEOUT`
+  - `OTEL_EXPORTER_OTLP_METRICS_TIMEOUT`
+  - `OTEL_EXPORTER_OTLP_CERTIFICATE`
+  - `OTEL_EXPORTER_OTLP_TRACES_CERTIFICATE`
+  - `OTEL_EXPORTER_OTLP_METRICS_CERTIFICATE`
+- Adds `otlpgrpc.WithTimeout` option for configuring timeout to the otlp/gRPC exporter. (#1821)
+- Adds `jaeger.WithMaxPacketSize` option for configuring maximum UDP packet size used when connecting to the Jaeger agent. (#1853)
+
+### Fixed
+
+- The `Span.IsRecording` implementation from `go.opentelemetry.io/otel/sdk/trace` always returns false when not being sampled. (#1750)
+- The Jaeger exporter now correctly sets tags for the Span status code and message.
+  This means it uses the correct tag keys (`"otel.status_code"`, `"otel.status_description"`) and does not set the status message as a tag unless it is set on the span. (#1761)
+- The Jaeger exporter now correctly records Span event's names using the `"event"` key for a tag.
+  Additionally, this tag is overridden, as specified in the OTel specification, if the event contains an attribute with that key. (#1768)
+- Zipkin Exporter: Ensure mapping between OTel and Zipkin span data complies with the specification. (#1688)
+- Fixed typo for default service name in Jaeger Exporter. (#1797)
+- Fix flaky OTLP for the reconnnection of the client connection. (#1527, #1814)
+- Fix Jaeger exporter dropping of span batches that exceed the UDP packet size limit.
+  Instead, the exporter now splits the batch into smaller sendable batches. (#1828)
+
+### Changed
+
+- Span `RecordError` now records an `exception` event to comply with the semantic convention specification. (#1492)
+- Jaeger exporter was updated to use thrift v0.14.1. (#1712)
+- Migrate from using internally built and maintained version of the OTLP to the one hosted at `go.opentelemetry.io/proto/otlp`. (#1713)
+- Migrate from using `github.com/gogo/protobuf` to `google.golang.org/protobuf` to match `go.opentelemetry.io/proto/otlp`. (#1713)
+- The storage of a local or remote Span in a `context.Context` using its SpanContext is unified to store just the current Span.
+  The Span's SpanContext can now self-identify as being remote or not.
+  This means that `"go.opentelemetry.io/otel/trace".ContextWithRemoteSpanContext` will now overwrite any existing current Span, not just existing remote Spans, and make it the current Span in a `context.Context`. (#1731)
+- Improve OTLP/gRPC exporter connection errors. (#1737)
+- Information about a parent span context in a `"go.opentelemetry.io/otel/export/trace".SpanSnapshot` is unified in a new `Parent` field.
+  The existing `ParentSpanID` and `HasRemoteParent` fields are removed in favor of this. (#1748)
+- The `ParentContext` field of the `"go.opentelemetry.io/otel/sdk/trace".SamplingParameters` is updated to hold a `context.Context` containing the parent span.
+  This changes it to make `SamplingParameters` conform with the OpenTelemetry specification. (#1749)
+- Updated Jaeger Environment Variables: `JAEGER_ENDPOINT`, `JAEGER_USER`, `JAEGER_PASSWORD`
+  to `OTEL_EXPORTER_JAEGER_ENDPOINT`, `OTEL_EXPORTER_JAEGER_USER`, `OTEL_EXPORTER_JAEGER_PASSWORD` in compliance with OTel specification. (#1752)
+- Modify `BatchSpanProcessor.ForceFlush` to abort after timeout/cancellation. (#1757)
+- The `DroppedAttributeCount` field of the `Span` in the `go.opentelemetry.io/otel` package now only represents the number of attributes dropped for the span itself.
+  It no longer is a conglomerate of itself, events, and link attributes that have been dropped. (#1771)
+- Make `ExportSpans` in Jaeger Exporter honor context deadline. (#1773)
+- Modify Zipkin Exporter default service name, use default resource's serviceName instead of empty. (#1777)
+- The `go.opentelemetry.io/otel/sdk/export/trace` package is merged into the `go.opentelemetry.io/otel/sdk/trace` package. (#1778)
+- The prometheus.InstallNewPipeline example is moved from comment to example test (#1796)
+- The convenience functions for the stdout exporter have been updated to return the `TracerProvider` implementation and enable the shutdown of the exporter. (#1800)
+- Replace the flush function returned from the Jaeger exporter's convenience creation functions (`InstallNewPipeline` and `NewExportPipeline`) with the `TracerProvider` implementation they create.
+  This enables the caller to shutdown and flush using the related `TracerProvider` methods. (#1822)
+- Updated the Jaeger exporter to have a default endpoint, `http://localhost:14250`, for the collector. (#1824)
+- Changed the function `WithCollectorEndpoint` in the Jaeger exporter to no longer accept an endpoint as an argument.
+  The endpoint can be passed with the `CollectorEndpointOption` using the `WithEndpoint` function or by setting the `OTEL_EXPORTER_JAEGER_ENDPOINT` environment variable value appropriately. (#1824)
+- The Jaeger exporter no longer batches exported spans itself, instead it relies on the SDK's `BatchSpanProcessor` for this functionality. (#1830)
+- The Jaeger exporter creation functions (`NewRawExporter`, `NewExportPipeline`, and `InstallNewPipeline`) no longer accept the removed `Option` type as a variadic argument. (#1830)
+
+### Removed
+
+- Removed Jaeger Environment variables: `JAEGER_SERVICE_NAME`, `JAEGER_DISABLED`, `JAEGER_TAGS`
+  These environment variables will no longer be used to override values of the Jaeger exporter (#1752)
+- No longer set the links for a `Span` in `go.opentelemetry.io/otel/sdk/trace` that is configured to be a new root.
+  This is unspecified behavior that the OpenTelemetry community plans to standardize in the future.
+  To prevent backwards incompatible changes when it is specified, these links are removed. (#1726)
+- Setting error status while recording error with Span from oteltest package. (#1729)
+- The concept of a remote and local Span stored in a context is unified to just the current Span.
+  Because of this `"go.opentelemetry.io/otel/trace".RemoteSpanContextFromContext` is removed as it is no longer needed.
+  Instead, `"go.opentelemetry.io/otel/trace".SpanContextFromContex` can be used to return the current Span.
+  If needed, that Span's `SpanContext.IsRemote()` can then be used to determine if it is remote or not. (#1731)
+- The `HasRemoteParent` field of the `"go.opentelemetry.io/otel/sdk/trace".SamplingParameters` is removed.
+  This field is redundant to the information returned from the `Remote` method of the `SpanContext` held in the `ParentContext` field. (#1749)
+- The `trace.FlagsDebug` and `trace.FlagsDeferred` constants have been removed and will be localized to the B3 propagator. (#1770)
+- Remove `Process` configuration, `WithProcessFromEnv` and `ProcessFromEnv`, and type from the Jaeger exporter package.
+  The information that could be configured in the `Process` struct should be configured in a `Resource` instead. (#1776, #1804)
+- Remove the `WithDisabled` option from the Jaeger exporter.
+  To disable the exporter unregister it from the `TracerProvider` or use a no-operation `TracerProvider`. (#1806)
+- Removed the functions `CollectorEndpointFromEnv` and `WithCollectorEndpointOptionFromEnv` from the Jaeger exporter.
+  These functions for retrieving specific environment variable values are redundant of other internal functions and
+  are not intended for end user use. (#1824)
+- Removed the Jaeger exporter `WithSDKOptions` `Option`.
+  This option was used to set SDK options for the exporter creation convenience functions.
+  These functions are provided as a way to easily setup or install the exporter with what are deemed reasonable SDK settings for common use cases.
+  If the SDK needs to be configured differently, the `NewRawExporter` function and direct setup of the SDK with the desired settings should be used. (#1825)
+- The `WithBufferMaxCount` and `WithBatchMaxCount` `Option`s from the Jaeger exporter are removed.
+  The exporter no longer batches exports, instead relying on the SDK's `BatchSpanProcessor` for this functionality. (#1830)
+- The Jaeger exporter `Option` type is removed.
+  The type is no longer used by the exporter to configure anything.
+  All the previous configurations these options provided were duplicates of SDK configuration.
+  They have been removed in favor of using the SDK configuration and focuses the exporter configuration to be only about the endpoints it will send telemetry to. (#1830)
+
+## [0.19.0] - 2021-03-18
+
+### Added
+
+- Added `Marshaler` config option to `otlphttp` to enable otlp over json or protobufs. (#1586)
+- A `ForceFlush` method to the `"go.opentelemetry.io/otel/sdk/trace".TracerProvider` to flush all registered `SpanProcessor`s. (#1608)
+- Added `WithSampler` and `WithSpanLimits` to tracer provider. (#1633, #1702)
+- `"go.opentelemetry.io/otel/trace".SpanContext` now has a `remote` property, and `IsRemote()` predicate, that is true when the `SpanContext` has been extracted from remote context data. (#1701)
+- A `Valid` method to the `"go.opentelemetry.io/otel/attribute".KeyValue` type. (#1703)
+
+### Changed
+
+- `trace.SpanContext` is now immutable and has no exported fields. (#1573)
+  - `trace.NewSpanContext()` can be used in conjunction with the `trace.SpanContextConfig` struct to initialize a new `SpanContext` where all values are known.
+- Update the `ForceFlush` method signature to the `"go.opentelemetry.io/otel/sdk/trace".SpanProcessor` to accept a `context.Context` and return an error. (#1608)
+- Update the `Shutdown` method to the `"go.opentelemetry.io/otel/sdk/trace".TracerProvider` return an error on shutdown failure. (#1608)
+- The SimpleSpanProcessor will now shut down the enclosed `SpanExporter` and gracefully ignore subsequent calls to `OnEnd` after `Shutdown` is called. (#1612)
+- `"go.opentelemetry.io/sdk/metric/controller.basic".WithPusher` is replaced with `WithExporter` to provide consistent naming across project. (#1656)
+- Added non-empty string check for trace `Attribute` keys. (#1659)
+- Add `description` to SpanStatus only when `StatusCode` is set to error. (#1662)
+- Jaeger exporter falls back to `resource.Default`'s `service.name` if the exported Span does not have one. (#1673)
+- Jaeger exporter populates Jaeger's Span Process from Resource. (#1673)
+- Renamed the `LabelSet` method of `"go.opentelemetry.io/otel/sdk/resource".Resource` to `Set`. (#1692)
+- Changed `WithSDK` to `WithSDKOptions` to accept variadic arguments of `TracerProviderOption` type in `go.opentelemetry.io/otel/exporters/trace/jaeger` package. (#1693)
+- Changed `WithSDK` to `WithSDKOptions` to accept variadic arguments of `TracerProviderOption` type in `go.opentelemetry.io/otel/exporters/trace/zipkin` package. (#1693)
+
+### Removed
+
+- Removed `serviceName` parameter from Zipkin exporter and uses resource instead. (#1549)
+- Removed `WithConfig` from tracer provider to avoid overriding configuration. (#1633)
+- Removed the exported `SimpleSpanProcessor` and `BatchSpanProcessor` structs.
+   These are now returned as a SpanProcessor interface from their respective constructors. (#1638)
+- Removed `WithRecord()` from `trace.SpanOption` when creating a span. (#1660)
+- Removed setting status to `Error` while recording an error as a span event in `RecordError`. (#1663)
+- Removed `jaeger.WithProcess` configuration option. (#1673)
+- Removed `ApplyConfig` method from `"go.opentelemetry.io/otel/sdk/trace".TracerProvider` and the now unneeded `Config` struct. (#1693)
+
+### Fixed
+
+- Jaeger Exporter: Ensure mapping between OTEL and Jaeger span data complies with the specification. (#1626)
+- `SamplingResult.TraceState` is correctly propagated to a newly created span's `SpanContext`. (#1655)
+- The `otel-collector` example now correctly flushes metric events prior to shutting down the exporter. (#1678)
+- Do not set span status message in `SpanStatusFromHTTPStatusCode` if it can be inferred from `http.status_code`. (#1681)
+- Synchronization issues in global trace delegate implementation. (#1686)
+- Reduced excess memory usage by global `TracerProvider`. (#1687)
+
+## [0.18.0] - 2021-03-03
+
+### Added
+
+- Added `resource.Default()` for use with meter and tracer providers. (#1507)
+- `AttributePerEventCountLimit` and `AttributePerLinkCountLimit` for `SpanLimits`. (#1535)
+- Added `Keys()` method to `propagation.TextMapCarrier` and `propagation.HeaderCarrier` to adapt `http.Header` to this interface. (#1544)
+- Added `code` attributes to `go.opentelemetry.io/otel/semconv` package. (#1558)
+- Compatibility testing suite in the CI system for the following systems. (#1567)
+   | OS      | Go Version | Architecture |
+   | ------- | ---------- | ------------ |
+   | Ubuntu  | 1.15       | amd64        |
+   | Ubuntu  | 1.14       | amd64        |
+   | Ubuntu  | 1.15       | 386          |
+   | Ubuntu  | 1.14       | 386          |
+   | MacOS   | 1.15       | amd64        |
+   | MacOS   | 1.14       | amd64        |
+   | Windows | 1.15       | amd64        |
+   | Windows | 1.14       | amd64        |
+   | Windows | 1.15       | 386          |
+   | Windows | 1.14       | 386          |
+
+### Changed
+
+- Replaced interface `oteltest.SpanRecorder` with its existing implementation
+  `StandardSpanRecorder`. (#1542)
+- Default span limit values to 128. (#1535)
+- Rename `MaxEventsPerSpan`, `MaxAttributesPerSpan` and `MaxLinksPerSpan` to `EventCountLimit`, `AttributeCountLimit` and `LinkCountLimit`, and move these fields into `SpanLimits`. (#1535)
+- Renamed the `otel/label` package to `otel/attribute`. (#1541)
+- Vendor the Jaeger exporter's dependency on Apache Thrift. (#1551)
+- Parallelize the CI linting and testing. (#1567)
+- Stagger timestamps in exact aggregator tests. (#1569)
+- Changed all examples to use `WithBatchTimeout(5 * time.Second)` rather than `WithBatchTimeout(5)`. (#1621)
+- Prevent end-users from implementing some interfaces (#1575)
+
+  ```
+      "otel/exporters/otlp/otlphttp".Option
+      "otel/exporters/stdout".Option
+      "otel/oteltest".Option
+      "otel/trace".TracerOption
+      "otel/trace".SpanOption
+      "otel/trace".EventOption
+      "otel/trace".LifeCycleOption
+      "otel/trace".InstrumentationOption
+      "otel/sdk/resource".Option
+      "otel/sdk/trace".ParentBasedSamplerOption
+      "otel/sdk/trace".ReadOnlySpan
+      "otel/sdk/trace".ReadWriteSpan
+  ```
+
+### Removed
+
+- Removed attempt to resample spans upon changing the span name with `span.SetName()`. (#1545)
+- The `test-benchmark` is no longer a dependency of the `precommit` make target. (#1567)
+- Removed the `test-386` make target.
+   This was replaced with a full compatibility testing suite (i.e. multi OS/arch) in the CI system. (#1567)
+
+### Fixed
+
+- The sequential timing check of timestamps in the stdout exporter are now setup explicitly to be sequential (#1571). (#1572)
+- Windows build of Jaeger tests now compiles with OS specific functions (#1576). (#1577)
+- The sequential timing check of timestamps of go.opentelemetry.io/otel/sdk/metric/aggregator/lastvalue are now setup explicitly to be sequential (#1578). (#1579)
+- Validate tracestate header keys with vendors according to the W3C TraceContext specification (#1475). (#1581)
+- The OTLP exporter includes related labels for translations of a GaugeArray (#1563). (#1570)
+
+## [0.17.0] - 2021-02-12
+
+### Changed
+
+- Rename project default branch from `master` to `main`. (#1505)
+- Reverse order in which `Resource` attributes are merged, per change in spec. (#1501)
+- Add tooling to maintain "replace" directives in go.mod files automatically. (#1528)
+- Create new modules: otel/metric, otel/trace, otel/oteltest, otel/sdk/export/metric, otel/sdk/metric (#1528)
+- Move metric-related public global APIs from otel to otel/metric/global. (#1528)
+
+## Fixed
+
+- Fixed otlpgrpc reconnection issue.
+- The example code in the README.md of `go.opentelemetry.io/otel/exporters/otlp` is moved to a compiled example test and used the new `WithAddress` instead of `WithEndpoint`. (#1513)
+- The otel-collector example now uses the default OTLP receiver port of the collector.
+
+## [0.16.0] - 2021-01-13
+
+### Added
+
+- Add the `ReadOnlySpan` and `ReadWriteSpan` interfaces to provide better control for accessing span data. (#1360)
+- `NewGRPCDriver` function returns a `ProtocolDriver` that maintains a single gRPC connection to the collector. (#1369)
+- Added documentation about the project's versioning policy. (#1388)
+- Added `NewSplitDriver` for OTLP exporter that allows sending traces and metrics to different endpoints. (#1418)
+- Added codeql worfklow to GitHub Actions (#1428)
+- Added Gosec workflow to GitHub Actions (#1429)
+- Add new HTTP driver for OTLP exporter in `exporters/otlp/otlphttp`. Currently it only supports the binary protobuf payloads. (#1420)
+- Add an OpenCensus exporter bridge. (#1444)
+
+### Changed
+
+- Rename `internal/testing` to `internal/internaltest`. (#1449)
+- Rename `export.SpanData` to `export.SpanSnapshot` and use it only for exporting spans. (#1360)
+- Store the parent's full `SpanContext` rather than just its span ID in the `span` struct. (#1360)
+- Improve span duration accuracy. (#1360)
+- Migrated CI/CD from CircleCI to GitHub Actions (#1382)
+- Remove duplicate checkout from GitHub Actions workflow (#1407)
+- Metric `array` aggregator renamed `exact` to match its `aggregation.Kind` (#1412)
+- Metric `exact` aggregator includes per-point timestamps (#1412)
+- Metric stdout exporter uses MinMaxSumCount aggregator for ValueRecorder instruments (#1412)
+- `NewExporter` from `exporters/otlp` now takes a `ProtocolDriver` as a parameter. (#1369)
+- Many OTLP Exporter options became gRPC ProtocolDriver options. (#1369)
+- Unify endpoint API that related to OTel exporter. (#1401)
+- Optimize metric histogram aggregator to re-use its slice of buckets. (#1435)
+- Metric aggregator Count() and histogram Bucket.Counts are consistently `uint64`. (1430)
+- Histogram aggregator accepts functional options, uses default boundaries if none given. (#1434)
+- `SamplingResult` now passed a `Tracestate` from the parent `SpanContext` (#1432)
+- Moved gRPC driver for OTLP exporter to `exporters/otlp/otlpgrpc`. (#1420)
+- The `TraceContext` propagator now correctly propagates `TraceState` through the `SpanContext`. (#1447)
+- Metric Push and Pull Controller components are combined into a single "basic" Controller:
+  - `WithExporter()` and `Start()` to configure Push behavior
+  - `Start()` is optional; use `Collect()` and `ForEach()` for Pull behavior
+  - `Start()` and `Stop()` accept Context. (#1378)
+- The `Event` type is moved from the `otel/sdk/export/trace` package to the `otel/trace` API package. (#1452)
+
+### Removed
+
+- Remove `errUninitializedSpan` as its only usage is now obsolete. (#1360)
+- Remove Metric export functionality related to quantiles and summary data points: this is not specified (#1412)
+- Remove DDSketch metric aggregator; our intention is to re-introduce this as an option of the histogram aggregator after [new OTLP histogram data types](https://github.com/open-telemetry/opentelemetry-proto/pull/226) are released (#1412)
+
+### Fixed
+
+- `BatchSpanProcessor.Shutdown()` will now shutdown underlying `export.SpanExporter`. (#1443)
+
+## [0.15.0] - 2020-12-10
+
+### Added
+
+- The `WithIDGenerator` `TracerProviderOption` is added to the `go.opentelemetry.io/otel/trace` package to configure an `IDGenerator` for the `TracerProvider`. (#1363)
+
+### Changed
+
+- The Zipkin exporter now uses the Span status code to determine. (#1328)
+- `NewExporter` and `Start` functions in `go.opentelemetry.io/otel/exporters/otlp` now receive `context.Context` as a first parameter. (#1357)
+- Move the OpenCensus example into `example` directory. (#1359)
+- Moved the SDK's `internal.IDGenerator` interface in to the `sdk/trace` package to enable support for externally-defined ID generators. (#1363)
+- Bump `github.com/google/go-cmp` from 0.5.3 to 0.5.4 (#1374)
+- Bump `github.com/golangci/golangci-lint` in `/internal/tools` (#1375)
+
+### Fixed
+
+- Metric SDK `SumObserver` and `UpDownSumObserver` instruments correctness fixes. (#1381)
+
+## [0.14.0] - 2020-11-19
+
+### Added
+
+- An `EventOption` and the related `NewEventConfig` function are added to the `go.opentelemetry.io/otel` package to configure Span events. (#1254)
+- A `TextMapPropagator` and associated `TextMapCarrier` are added to the `go.opentelemetry.io/otel/oteltest` package to test `TextMap` type propagators and their use. (#1259)
+- `SpanContextFromContext` returns `SpanContext` from context. (#1255)
+- `TraceState` has been added to `SpanContext`. (#1340)
+- `DeploymentEnvironmentKey` added to `go.opentelemetry.io/otel/semconv` package. (#1323)
+- Add an OpenCensus to OpenTelemetry tracing bridge. (#1305)
+- Add a parent context argument to `SpanProcessor.OnStart` to follow the specification. (#1333)
+- Add missing tests for `sdk/trace/attributes_map.go`. (#1337)
+
+### Changed
+
+- Move the `go.opentelemetry.io/otel/api/trace` package into `go.opentelemetry.io/otel/trace` with the following changes. (#1229) (#1307)
+  - `ID` has been renamed to `TraceID`.
+  - `IDFromHex` has been renamed to `TraceIDFromHex`.
+  - `EmptySpanContext` is removed.
+- Move the `go.opentelemetry.io/otel/api/trace/tracetest` package into `go.opentelemetry.io/otel/oteltest`. (#1229)
+- OTLP Exporter updates:
+  - supports OTLP v0.6.0 (#1230, #1354)
+  - supports configurable aggregation temporality (default: Cumulative, optional: Stateless). (#1296)
+- The Sampler is now called on local child spans. (#1233)
+- The `Kind` type from the `go.opentelemetry.io/otel/api/metric` package was renamed to `InstrumentKind` to more specifically describe what it is and avoid semantic ambiguity. (#1240)
+- The `MetricKind` method of the `Descriptor` type in the `go.opentelemetry.io/otel/api/metric` package was renamed to `Descriptor.InstrumentKind`.
+   This matches the returned type and fixes misuse of the term metric. (#1240)
+- Move test harness from the `go.opentelemetry.io/otel/api/apitest` package into `go.opentelemetry.io/otel/oteltest`. (#1241)
+- Move the `go.opentelemetry.io/otel/api/metric/metrictest` package into `go.opentelemetry.io/oteltest` as part of #964. (#1252)
+- Move the `go.opentelemetry.io/otel/api/metric` package into `go.opentelemetry.io/otel/metric` as part of #1303. (#1321)
+- Move the `go.opentelemetry.io/otel/api/metric/registry` package into `go.opentelemetry.io/otel/metric/registry` as a part of #1303. (#1316)
+- Move the `Number` type (together with related functions) from `go.opentelemetry.io/otel/api/metric` package into `go.opentelemetry.io/otel/metric/number` as a part of #1303. (#1316)
+- The function signature of the Span `AddEvent` method in `go.opentelemetry.io/otel` is updated to no longer take an unused context and instead take a required name and a variable number of `EventOption`s. (#1254)
+- The function signature of the Span `RecordError` method in `go.opentelemetry.io/otel` is updated to no longer take an unused context and instead take a required error value and a variable number of `EventOption`s. (#1254)
+- Move the `go.opentelemetry.io/otel/api/global` package to `go.opentelemetry.io/otel`. (#1262) (#1330)
+- Move the `Version` function from `go.opentelemetry.io/otel/sdk` to `go.opentelemetry.io/otel`. (#1330)
+- Rename correlation context header from `"otcorrelations"` to `"baggage"` to match the OpenTelemetry specification. (#1267)
+- Fix `Code.UnmarshalJSON` to work with valid JSON only. (#1276)
+- The `resource.New()` method changes signature to support builtin attributes and functional options, including `telemetry.sdk.*` and
+  `host.name` semantic conventions; the former method is renamed `resource.NewWithAttributes`. (#1235)
+- The Prometheus exporter now exports non-monotonic counters (i.e. `UpDownCounter`s) as gauges. (#1210)
+- Correct the `Span.End` method documentation in the `otel` API to state updates are not allowed on a span after it has ended. (#1310)
+- Updated span collection limits for attribute, event and link counts to 1000 (#1318)
+- Renamed `semconv.HTTPUrlKey` to `semconv.HTTPURLKey`. (#1338)
+
+### Removed
+
+- The `ErrInvalidHexID`, `ErrInvalidTraceIDLength`, `ErrInvalidSpanIDLength`, `ErrInvalidSpanIDLength`, or `ErrNilSpanID` from the `go.opentelemetry.io/otel` package are unexported now. (#1243)
+- The `AddEventWithTimestamp` method on the `Span` interface in `go.opentelemetry.io/otel` is removed due to its redundancy.
+   It is replaced by using the `AddEvent` method with a `WithTimestamp` option. (#1254)
+- The `MockSpan` and `MockTracer` types are removed from `go.opentelemetry.io/otel/oteltest`.
+   `Tracer` and `Span` from the same module should be used in their place instead. (#1306)
+- `WorkerCount` option is removed from `go.opentelemetry.io/otel/exporters/otlp`. (#1350)
+- Remove the following labels types: INT32, UINT32, UINT64 and FLOAT32. (#1314)
+
+### Fixed
+
+- Rename `MergeItererator` to `MergeIterator` in the `go.opentelemetry.io/otel/label` package. (#1244)
+- The `go.opentelemetry.io/otel/api/global` packages global TextMapPropagator now delegates functionality to a globally set delegate for all previously returned propagators. (#1258)
+- Fix condition in `label.Any`. (#1299)
+- Fix global `TracerProvider` to pass options to its configured provider. (#1329)
+- Fix missing handler for `ExactKind` aggregator in OTLP metrics transformer (#1309)
+
+## [0.13.0] - 2020-10-08
+
+### Added
+
+- OTLP Metric exporter supports Histogram aggregation. (#1209)
+- The `Code` struct from the `go.opentelemetry.io/otel/codes` package now supports JSON marshaling and unmarshaling as well as implements the `Stringer` interface. (#1214)
+- A Baggage API to implement the OpenTelemetry specification. (#1217)
+- Add Shutdown method to sdk/trace/provider, shutdown processors in the order they were registered. (#1227)
+
+### Changed
+
+- Set default propagator to no-op propagator. (#1184)
+- The `HTTPSupplier`, `HTTPExtractor`, `HTTPInjector`, and `HTTPPropagator` from the `go.opentelemetry.io/otel/api/propagation` package were replaced with unified `TextMapCarrier` and `TextMapPropagator` in the `go.opentelemetry.io/otel/propagation` package. (#1212) (#1325)
+- The `New` function from the `go.opentelemetry.io/otel/api/propagation` package was replaced with `NewCompositeTextMapPropagator` in the `go.opentelemetry.io/otel` package. (#1212)
+- The status codes of the `go.opentelemetry.io/otel/codes` package have been updated to match the latest OpenTelemetry specification.
+   They now are `Unset`, `Error`, and `Ok`.
+   They no longer track the gRPC codes. (#1214)
+- The `StatusCode` field of the `SpanData` struct in the `go.opentelemetry.io/otel/sdk/export/trace` package now uses the codes package from this package instead of the gRPC project. (#1214)
+- Move the `go.opentelemetry.io/otel/api/baggage` package into `go.opentelemetry.io/otel/baggage`. (#1217) (#1325)
+- A `Shutdown` method of `SpanProcessor` and all its implementations receives a context and returns an error. (#1264)
+
+### Fixed
+
+- Copies of data from arrays and slices passed to `go.opentelemetry.io/otel/label.ArrayValue()` are now used in the returned `Value` instead of using the mutable data itself. (#1226)
+
+### Removed
+
+- The `ExtractHTTP` and `InjectHTTP` functions from the `go.opentelemetry.io/otel/api/propagation` package were removed. (#1212)
+- The `Propagators` interface from the `go.opentelemetry.io/otel/api/propagation` package was removed to conform to the OpenTelemetry specification.
+   The explicit `TextMapPropagator` type can be used in its place as this is the `Propagator` type the specification defines. (#1212)
+- The `SetAttribute` method of the `Span` from the `go.opentelemetry.io/otel/api/trace` package was removed given its redundancy with the `SetAttributes` method. (#1216)
+- The internal implementation of Baggage storage is removed in favor of using the new Baggage API functionality. (#1217)
+- Remove duplicate hostname key `HostHostNameKey` in Resource semantic conventions. (#1219)
+- Nested array/slice support has been removed. (#1226)
+
+## [0.12.0] - 2020-09-24
+
+### Added
+
+- A `SpanConfigure` function in `go.opentelemetry.io/otel/api/trace` to create a new `SpanConfig` from `SpanOption`s. (#1108)
+- In the `go.opentelemetry.io/otel/api/trace` package, `NewTracerConfig` was added to construct new `TracerConfig`s.
+   This addition was made to conform with our project option conventions. (#1155)
+- Instrumentation library information was added to the Zipkin exporter. (#1119)
+- The `SpanProcessor` interface now has a `ForceFlush()` method. (#1166)
+- More semantic conventions for k8s as resource attributes. (#1167)
+
+### Changed
+
+- Add reconnecting udp connection type to Jaeger exporter.
+   This change adds a new optional implementation of the udp conn interface used to detect changes to an agent's host dns record.
+   It then adopts the new destination address to ensure the exporter doesn't get stuck. This change was ported from jaegertracing/jaeger-client-go#520. (#1063)
+- Replace `StartOption` and `EndOption` in `go.opentelemetry.io/otel/api/trace` with `SpanOption`.
+   This change is matched by replacing the `StartConfig` and `EndConfig` with a unified `SpanConfig`. (#1108)
+- Replace the `LinkedTo` span option in `go.opentelemetry.io/otel/api/trace` with `WithLinks`.
+   This is be more consistent with our other option patterns, i.e. passing the item to be configured directly instead of its component parts, and provides a cleaner function signature. (#1108)
+- The `go.opentelemetry.io/otel/api/trace` `TracerOption` was changed to an interface to conform to project option conventions. (#1109)
+- Move the `B3` and `TraceContext` from within the `go.opentelemetry.io/otel/api/trace` package to their own `go.opentelemetry.io/otel/propagators` package.
+    This removal of the propagators is reflective of the OpenTelemetry specification for these propagators as well as cleans up the `go.opentelemetry.io/otel/api/trace` API. (#1118)
+- Rename Jaeger tags used for instrumentation library information to reflect changes in OpenTelemetry specification. (#1119)
+- Rename `ProbabilitySampler` to `TraceIDRatioBased` and change semantics to ignore parent span sampling status. (#1115)
+- Move `tools` package under `internal`. (#1141)
+- Move `go.opentelemetry.io/otel/api/correlation` package to `go.opentelemetry.io/otel/api/baggage`. (#1142)
+   The `correlation.CorrelationContext` propagator has been renamed `baggage.Baggage`.  Other exported functions and types are unchanged.
+- Rename `ParentOrElse` sampler to `ParentBased` and allow setting samplers depending on parent span. (#1153)
+- In the `go.opentelemetry.io/otel/api/trace` package, `SpanConfigure` was renamed to `NewSpanConfig`. (#1155)
+- Change `dependabot.yml` to add a `Skip Changelog` label to dependabot-sourced PRs. (#1161)
+- The [configuration style guide](https://github.com/open-telemetry/opentelemetry-go/blob/master/CONTRIBUTING.md#config) has been updated to
+   recommend the use of `newConfig()` instead of `configure()`. (#1163)
+- The `otlp.Config` type has been unexported and changed to `otlp.config`, along with its initializer. (#1163)
+- Ensure exported interface types include parameter names and update the
+   Style Guide to reflect this styling rule. (#1172)
+- Don't consider unset environment variable for resource detection to be an error. (#1170)
+- Rename `go.opentelemetry.io/otel/api/metric.ConfigureInstrument` to `NewInstrumentConfig` and
+  `go.opentelemetry.io/otel/api/metric.ConfigureMeter` to `NewMeterConfig`.
+- ValueObserver instruments use LastValue aggregator by default. (#1165)
+- OTLP Metric exporter supports LastValue aggregation. (#1165)
+- Move the `go.opentelemetry.io/otel/api/unit` package to `go.opentelemetry.io/otel/unit`. (#1185)
+- Rename `Provider` to `MeterProvider` in the `go.opentelemetry.io/otel/api/metric` package. (#1190)
+- Rename `NoopProvider` to `NoopMeterProvider` in the `go.opentelemetry.io/otel/api/metric` package. (#1190)
+- Rename `NewProvider` to `NewMeterProvider` in the `go.opentelemetry.io/otel/api/metric/metrictest` package. (#1190)
+- Rename `Provider` to `MeterProvider` in the `go.opentelemetry.io/otel/api/metric/registry` package. (#1190)
+- Rename `NewProvider` to `NewMeterProvider` in the `go.opentelemetry.io/otel/api/metri/registryc` package. (#1190)
+- Rename `Provider` to `TracerProvider` in the `go.opentelemetry.io/otel/api/trace` package. (#1190)
+- Rename `NoopProvider` to `NoopTracerProvider` in the `go.opentelemetry.io/otel/api/trace` package. (#1190)
+- Rename `Provider` to `TracerProvider` in the `go.opentelemetry.io/otel/api/trace/tracetest` package. (#1190)
+- Rename `NewProvider` to `NewTracerProvider` in the `go.opentelemetry.io/otel/api/trace/tracetest` package. (#1190)
+- Rename `WrapperProvider` to `WrapperTracerProvider` in the `go.opentelemetry.io/otel/bridge/opentracing` package. (#1190)
+- Rename `NewWrapperProvider` to `NewWrapperTracerProvider` in the `go.opentelemetry.io/otel/bridge/opentracing` package. (#1190)
+- Rename `Provider` method of the pull controller to `MeterProvider` in the `go.opentelemetry.io/otel/sdk/metric/controller/pull` package. (#1190)
+- Rename `Provider` method of the push controller to `MeterProvider` in the `go.opentelemetry.io/otel/sdk/metric/controller/push` package. (#1190)
+- Rename `ProviderOptions` to `TracerProviderConfig` in the `go.opentelemetry.io/otel/sdk/trace` package. (#1190)
+- Rename `ProviderOption` to `TracerProviderOption` in the `go.opentelemetry.io/otel/sdk/trace` package. (#1190)
+- Rename `Provider` to `TracerProvider` in the `go.opentelemetry.io/otel/sdk/trace` package. (#1190)
+- Rename `NewProvider` to `NewTracerProvider` in the `go.opentelemetry.io/otel/sdk/trace` package. (#1190)
+- Renamed `SamplingDecision` values to comply with OpenTelemetry specification change. (#1192)
+- Renamed Zipkin attribute names from `ot.status_code & ot.status_description` to `otel.status_code & otel.status_description`. (#1201)
+- The default SDK now invokes registered `SpanProcessor`s in the order they were registered with the `TracerProvider`. (#1195)
+- Add test of spans being processed by the `SpanProcessor`s in the order they were registered. (#1203)
+
+### Removed
+
+- Remove the B3 propagator from `go.opentelemetry.io/otel/propagators`. It is now located in the
+   `go.opentelemetry.io/contrib/propagators/` module. (#1191)
+- Remove the semantic convention for HTTP status text, `HTTPStatusTextKey` from package `go.opentelemetry.io/otel/semconv`. (#1194)
+
+### Fixed
+
+- Zipkin example no longer mentions `ParentSampler`, corrected to `ParentBased`. (#1171)
+- Fix missing shutdown processor in otel-collector example. (#1186)
+- Fix missing shutdown processor in basic and namedtracer examples. (#1197)
+
+## [0.11.0] - 2020-08-24
+
+### Added
+
+- Support for exporting array-valued attributes via OTLP. (#992)
+- `Noop` and `InMemory` `SpanBatcher` implementations to help with testing integrations. (#994)
+- Support for filtering metric label sets. (#1047)
+- A dimensionality-reducing metric Processor. (#1057)
+- Integration tests for more OTel Collector Attribute types. (#1062)
+- A new `WithSpanProcessor` `ProviderOption` is added to the `go.opentelemetry.io/otel/sdk/trace` package to create a `Provider` and automatically register the `SpanProcessor`. (#1078)
+
+### Changed
+
+- Rename `sdk/metric/processor/test` to `sdk/metric/processor/processortest`. (#1049)
+- Rename `sdk/metric/controller/test` to `sdk/metric/controller/controllertest`. (#1049)
+- Rename `api/testharness` to `api/apitest`. (#1049)
+- Rename `api/trace/testtrace` to `api/trace/tracetest`. (#1049)
+- Change Metric Processor to merge multiple observations. (#1024)
+- The `go.opentelemetry.io/otel/bridge/opentracing` bridge package has been made into its own module.
+   This removes the package dependencies of this bridge from the rest of the OpenTelemetry based project. (#1038)
+- Renamed `go.opentelemetry.io/otel/api/standard` package to `go.opentelemetry.io/otel/semconv` to avoid the ambiguous and generic name `standard` and better describe the package as containing OpenTelemetry semantic conventions. (#1016)
+- The environment variable used for resource detection has been changed from `OTEL_RESOURCE_LABELS` to `OTEL_RESOURCE_ATTRIBUTES` (#1042)
+- Replace `WithSyncer` with `WithBatcher` in examples. (#1044)
+- Replace the `google.golang.org/grpc/codes` dependency in the API with an equivalent `go.opentelemetry.io/otel/codes` package. (#1046)
+- Merge the `go.opentelemetry.io/otel/api/label` and `go.opentelemetry.io/otel/api/kv` into the new `go.opentelemetry.io/otel/label` package. (#1060)
+- Unify Callback Function Naming.
+   Rename `*Callback` with `*Func`. (#1061)
+- CI builds validate against last two versions of Go, dropping 1.13 and adding 1.15. (#1064)
+- The `go.opentelemetry.io/otel/sdk/export/trace` interfaces `SpanSyncer` and `SpanBatcher` have been replaced with a specification compliant `Exporter` interface.
+   This interface still supports the export of `SpanData`, but only as a slice.
+   Implementation are also required now to return any error from `ExportSpans` if one occurs as well as implement a `Shutdown` method for exporter clean-up. (#1078)
+- The `go.opentelemetry.io/otel/sdk/trace` `NewBatchSpanProcessor` function no longer returns an error.
+   If a `nil` exporter is passed as an argument to this function, instead of it returning an error, it now returns a `BatchSpanProcessor` that handles the export of `SpanData` by not taking any action. (#1078)
+- The `go.opentelemetry.io/otel/sdk/trace` `NewProvider` function to create a `Provider` no longer returns an error, instead only a `*Provider`.
+   This change is related to `NewBatchSpanProcessor` not returning an error which was the only error this function would return. (#1078)
+
+### Removed
+
+- Duplicate, unused API sampler interface. (#999)
+   Use the [`Sampler` interface](https://github.com/open-telemetry/opentelemetry-go/blob/v0.11.0/sdk/trace/sampling.go) provided by the SDK instead.
+- The `grpctrace` instrumentation was moved to the `go.opentelemetry.io/contrib` repository and out of this repository.
+   This move includes moving the `grpc` example to the `go.opentelemetry.io/contrib` as well. (#1027)
+- The `WithSpan` method of the `Tracer` interface.
+   The functionality this method provided was limited compared to what a user can provide themselves.
+   It was removed with the understanding that if there is sufficient user need it can be added back based on actual user usage. (#1043)
+- The `RegisterSpanProcessor` and `UnregisterSpanProcessor` functions.
+   These were holdovers from an approach prior to the TracerProvider design. They were not used anymore. (#1077)
+- The `oterror` package. (#1026)
+- The `othttp` and `httptrace` instrumentations were moved to `go.opentelemetry.io/contrib`. (#1032)
+
+### Fixed
+
+- The `semconv.HTTPServerMetricAttributesFromHTTPRequest()` function no longer generates the high-cardinality `http.request.content.length` label. (#1031)
+- Correct instrumentation version tag in Jaeger exporter. (#1037)
+- The SDK span will now set an error event if the `End` method is called during a panic (i.e. it was deferred). (#1043)
+- Move internally generated protobuf code from the `go.opentelemetry.io/otel` to the OTLP exporter to reduce dependency overhead. (#1050)
+- The `otel-collector` example referenced outdated collector processors. (#1006)
+
+## [0.10.0] - 2020-07-29
+
+This release migrates the default OpenTelemetry SDK into its own Go module, decoupling the SDK from the API and reducing dependencies for instrumentation packages.
+
+### Added
+
+- The Zipkin exporter now has `NewExportPipeline` and `InstallNewPipeline` constructor functions to match the common pattern.
+    These function build a new exporter with default SDK options and register the exporter with the `global` package respectively. (#944)
+- Add propagator option for gRPC instrumentation. (#986)
+- The `testtrace` package now tracks the `trace.SpanKind` for each span. (#987)
+
+### Changed
+
+- Replace the `RegisterGlobal` `Option` in the Jaeger exporter with an `InstallNewPipeline` constructor function.
+   This matches the other exporter constructor patterns and will register a new exporter after building it with default configuration. (#944)
+- The trace (`go.opentelemetry.io/otel/exporters/trace/stdout`) and metric (`go.opentelemetry.io/otel/exporters/metric/stdout`) `stdout` exporters are now merged into a single exporter at `go.opentelemetry.io/otel/exporters/stdout`.
+   This new exporter was made into its own Go module to follow the pattern of all exporters and decouple it from the `go.opentelemetry.io/otel` module. (#956, #963)
+- Move the `go.opentelemetry.io/otel/exporters/test` test package to `go.opentelemetry.io/otel/sdk/export/metric/metrictest`. (#962)
+- The `go.opentelemetry.io/otel/api/kv/value` package was merged into the parent `go.opentelemetry.io/otel/api/kv` package. (#968)
+  - `value.Bool` was replaced with `kv.BoolValue`.
+  - `value.Int64` was replaced with `kv.Int64Value`.
+  - `value.Uint64` was replaced with `kv.Uint64Value`.
+  - `value.Float64` was replaced with `kv.Float64Value`.
+  - `value.Int32` was replaced with `kv.Int32Value`.
+  - `value.Uint32` was replaced with `kv.Uint32Value`.
+  - `value.Float32` was replaced with `kv.Float32Value`.
+  - `value.String` was replaced with `kv.StringValue`.
+  - `value.Int` was replaced with `kv.IntValue`.
+  - `value.Uint` was replaced with `kv.UintValue`.
+  - `value.Array` was replaced with `kv.ArrayValue`.
+- Rename `Infer` to `Any` in the `go.opentelemetry.io/otel/api/kv` package. (#972)
+- Change `othttp` to use the `httpsnoop` package to wrap the `ResponseWriter` so that optional interfaces (`http.Hijacker`, `http.Flusher`, etc.) that are implemented by the original `ResponseWriter`are also implemented by the wrapped `ResponseWriter`. (#979)
+- Rename `go.opentelemetry.io/otel/sdk/metric/aggregator/test` package to `go.opentelemetry.io/otel/sdk/metric/aggregator/aggregatortest`. (#980)
+- Make the SDK into its own Go module called `go.opentelemetry.io/otel/sdk`. (#985)
+- Changed the default trace `Sampler` from `AlwaysOn` to `ParentOrElse(AlwaysOn)`. (#989)
+
+### Removed
+
+- The `IndexedAttribute` function from the `go.opentelemetry.io/otel/api/label` package was removed in favor of `IndexedLabel` which it was synonymous with. (#970)
+
+### Fixed
+
+- Bump github.com/golangci/golangci-lint from 1.28.3 to 1.29.0 in /tools. (#953)
+- Bump github.com/google/go-cmp from 0.5.0 to 0.5.1. (#957)
+- Use `global.Handle` for span export errors in the OTLP exporter. (#946)
+- Correct Go language formatting in the README documentation. (#961)
+- Remove default SDK dependencies from the `go.opentelemetry.io/otel/api` package. (#977)
+- Remove default SDK dependencies from the `go.opentelemetry.io/otel/instrumentation` package. (#983)
+- Move documented examples for `go.opentelemetry.io/otel/instrumentation/grpctrace` interceptors into Go example tests. (#984)
+
+## [0.9.0] - 2020-07-20
+
+### Added
+
+- A new Resource Detector interface is included to allow resources to be automatically detected and included. (#939)
+- A Detector to automatically detect resources from an environment variable. (#939)
+- Github action to generate protobuf Go bindings locally in `internal/opentelemetry-proto-gen`. (#938)
+- OTLP .proto files from `open-telemetry/opentelemetry-proto` imported as a git submodule under `internal/opentelemetry-proto`.
+   References to `github.com/open-telemetry/opentelemetry-proto` changed to `go.opentelemetry.io/otel/internal/opentelemetry-proto-gen`. (#942)
+
+### Changed
+
+- Non-nil value `struct`s for key-value pairs will be marshalled using JSON rather than `Sprintf`. (#948)
+
+### Removed
+
+- Removed dependency on `github.com/open-telemetry/opentelemetry-collector`. (#943)
+
+## [0.8.0] - 2020-07-09
+
+### Added
+
+- The `B3Encoding` type to represent the B3 encoding(s) the B3 propagator can inject.
+   A value for HTTP supported encodings (Multiple Header: `MultipleHeader`, Single Header: `SingleHeader`) are included. (#882)
+- The `FlagsDeferred` trace flag to indicate if the trace sampling decision has been deferred. (#882)
+- The `FlagsDebug` trace flag to indicate if the trace is a debug trace. (#882)
+- Add `peer.service` semantic attribute. (#898)
+- Add database-specific semantic attributes. (#899)
+- Add semantic convention for `faas.coldstart` and `container.id`. (#909)
+- Add http content size semantic conventions. (#905)
+- Include `http.request_content_length` in HTTP request basic attributes. (#905)
+- Add semantic conventions for operating system process resource attribute keys. (#919)
+- The Jaeger exporter now has a `WithBatchMaxCount` option to specify the maximum number of spans sent in a batch. (#931)
+
+### Changed
+
+- Update `CONTRIBUTING.md` to ask for updates to `CHANGELOG.md` with each pull request. (#879)
+- Use lowercase header names for B3 Multiple Headers. (#881)
+- The B3 propagator `SingleHeader` field has been replaced with `InjectEncoding`.
+   This new field can be set to combinations of the `B3Encoding` bitmasks and will inject trace information in these encodings.
+   If no encoding is set, the propagator will default to `MultipleHeader` encoding. (#882)
+- The B3 propagator now extracts from either HTTP encoding of B3 (Single Header or Multiple Header) based on what is contained in the header.
+   Preference is given to Single Header encoding with Multiple Header being the fallback if Single Header is not found or is invalid.
+   This behavior change is made to dynamically support all correctly encoded traces received instead of having to guess the expected encoding prior to receiving. (#882)
+- Extend semantic conventions for RPC. (#900)
+- To match constant naming conventions in the `api/standard` package, the `FaaS*` key names are appended with a suffix of `Key`. (#920)
+  - `"api/standard".FaaSName` -> `FaaSNameKey`
+  - `"api/standard".FaaSID` -> `FaaSIDKey`
+  - `"api/standard".FaaSVersion` -> `FaaSVersionKey`
+  - `"api/standard".FaaSInstance` -> `FaaSInstanceKey`
+
+### Removed
+
+- The `FlagsUnused` trace flag is removed.
+   The purpose of this flag was to act as the inverse of `FlagsSampled`, the inverse of `FlagsSampled` is used instead. (#882)
+- The B3 header constants (`B3SingleHeader`, `B3DebugFlagHeader`, `B3TraceIDHeader`, `B3SpanIDHeader`, `B3SampledHeader`, `B3ParentSpanIDHeader`) are removed.
+   If B3 header keys are needed [the authoritative OpenZipkin package constants](https://pkg.go.dev/github.com/openzipkin/zipkin-go@v0.2.2/propagation/b3?tab=doc#pkg-constants) should be used instead. (#882)
+
+### Fixed
+
+- The B3 Single Header name is now correctly `b3` instead of the previous `X-B3`. (#881)
+- The B3 propagator now correctly supports sampling only values (`b3: 0`, `b3: 1`, or `b3: d`) for a Single B3 Header. (#882)
+- The B3 propagator now propagates the debug flag.
+   This removes the behavior of changing the debug flag into a set sampling bit.
+   Instead, this now follow the B3 specification and omits the `X-B3-Sampling` header. (#882)
+- The B3 propagator now tracks "unset" sampling state (meaning "defer the decision") and does not set the `X-B3-Sampling` header when injecting. (#882)
+- Bump github.com/itchyny/gojq from 0.10.3 to 0.10.4 in /tools. (#883)
+- Bump github.com/opentracing/opentracing-go from v1.1.1-0.20190913142402-a7454ce5950e to v1.2.0. (#885)
+- The tracing time conversion for OTLP spans is now correctly set to `UnixNano`. (#896)
+- Ensure span status is not set to `Unknown` when no HTTP status code is provided as it is assumed to be `200 OK`. (#908)
+- Ensure `httptrace.clientTracer` closes `http.headers` span. (#912)
+- Prometheus exporter will not apply stale updates or forget inactive metrics. (#903)
+- Add test for api.standard `HTTPClientAttributesFromHTTPRequest`. (#905)
+- Bump github.com/golangci/golangci-lint from 1.27.0 to 1.28.1 in /tools. (#901, #913)
+- Update otel-colector example to use the v0.5.0 collector. (#915)
+- The `grpctrace` instrumentation uses a span name conforming to the OpenTelemetry semantic conventions (does not contain a leading slash (`/`)). (#922)
+- The `grpctrace` instrumentation includes an `rpc.method` attribute now set to the gRPC method name. (#900, #922)
+- The `grpctrace` instrumentation `rpc.service` attribute now contains the package name if one exists.
+   This is in accordance with OpenTelemetry semantic conventions. (#922)
+- Correlation Context extractor will no longer insert an empty map into the returned context when no valid values are extracted. (#923)
+- Bump google.golang.org/api from 0.28.0 to 0.29.0 in /exporters/trace/jaeger. (#925)
+- Bump github.com/itchyny/gojq from 0.10.4 to 0.11.0 in /tools. (#926)
+- Bump github.com/golangci/golangci-lint from 1.28.1 to 1.28.2 in /tools. (#930)
+
+## [0.7.0] - 2020-06-26
+
+This release implements the v0.5.0 version of the OpenTelemetry specification.
+
+### Added
+
+- The othttp instrumentation now includes default metrics. (#861)
+- This CHANGELOG file to track all changes in the project going forward.
+- Support for array type attributes. (#798)
+- Apply transitive dependabot go.mod dependency updates as part of a new automatic Github workflow. (#844)
+- Timestamps are now passed to exporters for each export. (#835)
+- Add new `Accumulation` type to metric SDK to transport telemetry from `Accumulator`s to `Processor`s.
+   This replaces the prior `Record` `struct` use for this purpose. (#835)
+- New dependabot integration to automate package upgrades. (#814)
+- `Meter` and `Tracer` implementations accept instrumentation version version as an optional argument.
+   This instrumentation version is passed on to exporters. (#811) (#805) (#802)
+- The OTLP exporter includes the instrumentation version in telemetry it exports. (#811)
+- Environment variables for Jaeger exporter are supported. (#796)
+- New `aggregation.Kind` in the export metric API. (#808)
+- New example that uses OTLP and the collector. (#790)
+- Handle errors in the span `SetName` during span initialization. (#791)
+- Default service config to enable retries for retry-able failed requests in the OTLP exporter and an option to override this default. (#777)
+- New `go.opentelemetry.io/otel/api/oterror` package to uniformly support error handling and definitions for the project. (#778)
+- New `global` default implementation of the `go.opentelemetry.io/otel/api/oterror.Handler` interface to be used to handle errors prior to an user defined `Handler`.
+   There is also functionality for the user to register their `Handler` as well as a convenience function `Handle` to handle an error with this global `Handler`(#778)
+- Options to specify propagators for httptrace and grpctrace instrumentation. (#784)
+- The required `application/json` header for the Zipkin exporter is included in all exports. (#774)
+- Integrate HTTP semantics helpers from the contrib repository into the `api/standard` package. #769
+
+### Changed
+
+- Rename `Integrator` to `Processor` in the metric SDK. (#863)
+- Rename `AggregationSelector` to `AggregatorSelector`. (#859)
+- Rename `SynchronizedCopy` to `SynchronizedMove`. (#858)
+- Rename `simple` integrator to `basic` integrator. (#857)
+- Merge otlp collector examples. (#841)
+- Change the metric SDK to support cumulative, delta, and pass-through exporters directly.
+   With these changes, cumulative and delta specific exporters are able to request the correct kind of aggregation from the SDK. (#840)
+- The `Aggregator.Checkpoint` API is renamed to `SynchronizedCopy` and adds an argument, a different `Aggregator` into which the copy is stored. (#812)
+- The `export.Aggregator` contract is that `Update()` and `SynchronizedCopy()` are synchronized with each other.
+   All the aggregation interfaces (`Sum`, `LastValue`, ...) are not meant to be synchronized, as the caller is expected to synchronize aggregators at a higher level after the `Accumulator`.
+   Some of the `Aggregators` used unnecessary locking and that has been cleaned up. (#812)
+- Use of `metric.Number` was replaced by `int64` now that we use `sync.Mutex` in the `MinMaxSumCount` and `Histogram` `Aggregators`. (#812)
+- Replace `AlwaysParentSample` with `ParentSample(fallback)` to match the OpenTelemetry v0.5.0 specification. (#810)
+- Rename `sdk/export/metric/aggregator` to `sdk/export/metric/aggregation`. #808
+- Send configured headers with every request in the OTLP exporter, instead of just on connection creation. (#806)
+- Update error handling for any one off error handlers, replacing, instead, with the `global.Handle` function. (#791)
+- Rename `plugin` directory to `instrumentation` to match the OpenTelemetry specification. (#779)
+- Makes the argument order to Histogram and DDSketch `New()` consistent. (#781)
+
+### Removed
+
+- `Uint64NumberKind` and related functions from the API. (#864)
+- Context arguments from `Aggregator.Checkpoint` and `Integrator.Process` as they were unused. (#803)
+- `SpanID` is no longer included in parameters for sampling decision to match the OpenTelemetry specification. (#775)
+
+### Fixed
+
+- Upgrade OTLP exporter to opentelemetry-proto matching the opentelemetry-collector v0.4.0 release. (#866)
+- Allow changes to `go.sum` and `go.mod` when running dependabot tidy-up. (#871)
+- Bump github.com/stretchr/testify from 1.4.0 to 1.6.1. (#824)
+- Bump github.com/prometheus/client_golang from 1.7.0 to 1.7.1 in /exporters/metric/prometheus. (#867)
+- Bump google.golang.org/grpc from 1.29.1 to 1.30.0 in /exporters/trace/jaeger. (#853)
+- Bump google.golang.org/grpc from 1.29.1 to 1.30.0 in /exporters/trace/zipkin. (#854)
+- Bumps github.com/golang/protobuf from 1.3.2 to 1.4.2 (#848)
+- Bump github.com/stretchr/testify from 1.4.0 to 1.6.1 in /exporters/otlp (#817)
+- Bump github.com/golangci/golangci-lint from 1.25.1 to 1.27.0 in /tools (#828)
+- Bump github.com/prometheus/client_golang from 1.5.0 to 1.7.0 in /exporters/metric/prometheus (#838)
+- Bump github.com/stretchr/testify from 1.4.0 to 1.6.1 in /exporters/trace/jaeger (#829)
+- Bump github.com/benbjohnson/clock from 1.0.0 to 1.0.3 (#815)
+- Bump github.com/stretchr/testify from 1.4.0 to 1.6.1 in /exporters/trace/zipkin (#823)
+- Bump github.com/itchyny/gojq from 0.10.1 to 0.10.3 in /tools (#830)
+- Bump github.com/stretchr/testify from 1.4.0 to 1.6.1 in /exporters/metric/prometheus (#822)
+- Bump google.golang.org/grpc from 1.27.1 to 1.29.1 in /exporters/trace/zipkin (#820)
+- Bump google.golang.org/grpc from 1.27.1 to 1.29.1 in /exporters/trace/jaeger (#831)
+- Bump github.com/google/go-cmp from 0.4.0 to 0.5.0 (#836)
+- Bump github.com/google/go-cmp from 0.4.0 to 0.5.0 in /exporters/trace/jaeger (#837)
+- Bump github.com/google/go-cmp from 0.4.0 to 0.5.0 in /exporters/otlp (#839)
+- Bump google.golang.org/api from 0.20.0 to 0.28.0 in /exporters/trace/jaeger (#843)
+- Set span status from HTTP status code in the othttp instrumentation. (#832)
+- Fixed typo in push controller comment. (#834)
+- The `Aggregator` testing has been updated and cleaned. (#812)
+- `metric.Number(0)` expressions are replaced by `0` where possible. (#812)
+- Fixed `global` `handler_test.go` test failure. #804
+- Fixed `BatchSpanProcessor.Shutdown` to wait until all spans are processed. (#766)
+- Fixed OTLP example's accidental early close of exporter. (#807)
+- Ensure zipkin exporter reads and closes response body. (#788)
+- Update instrumentation to use `api/standard` keys instead of custom keys. (#782)
+- Clean up tools and RELEASING documentation. (#762)
+
+## [0.6.0] - 2020-05-21
+
+### Added
+
+- Support for `Resource`s in the prometheus exporter. (#757)
+- New pull controller. (#751)
+- New `UpDownSumObserver` instrument. (#750)
+- OpenTelemetry collector demo. (#711)
+- New `SumObserver` instrument. (#747)
+- New `UpDownCounter` instrument. (#745)
+- New timeout `Option` and configuration function `WithTimeout` to the push controller. (#742)
+- New `api/standards` package to implement semantic conventions and standard key-value generation. (#731)
+
+### Changed
+
+- Rename `Register*` functions in the metric API to `New*` for all `Observer` instruments. (#761)
+- Use `[]float64` for histogram boundaries, not `[]metric.Number`. (#758)
+- Change OTLP example to use exporter as a trace `Syncer` instead of as an unneeded `Batcher`. (#756)
+- Replace `WithResourceAttributes()` with `WithResource()` in the trace SDK. (#754)
+- The prometheus exporter now uses the new pull controller. (#751)
+- Rename `ScheduleDelayMillis` to `BatchTimeout` in the trace `BatchSpanProcessor`.(#752)
+- Support use of synchronous instruments in asynchronous callbacks (#725)
+- Move `Resource` from the `Export` method parameter into the metric export `Record`. (#739)
+- Rename `Observer` instrument to `ValueObserver`. (#734)
+- The push controller now has a method (`Provider()`) to return a `metric.Provider` instead of the old `Meter` method that acted as a `metric.Provider`. (#738)
+- Replace `Measure` instrument by `ValueRecorder` instrument. (#732)
+- Rename correlation context header from `"Correlation-Context"` to `"otcorrelations"` to match the OpenTelemetry specification. (#727)
+
+### Fixed
+
+- Ensure gRPC `ClientStream` override methods do not panic in grpctrace package. (#755)
+- Disable parts of `BatchSpanProcessor` test until a fix is found. (#743)
+- Fix `string` case in `kv` `Infer` function. (#746)
+- Fix panic in grpctrace client interceptors. (#740)
+- Refactor the `api/metrics` push controller and add `CheckpointSet` synchronization. (#737)
+- Rewrite span batch process queue batching logic. (#719)
+- Remove the push controller named Meter map. (#738)
+- Fix Histogram aggregator initial state (fix #735). (#736)
+- Ensure golang alpine image is running `golang-1.14` for examples. (#733)
+- Added test for grpctrace `UnaryInterceptorClient`. (#695)
+- Rearrange `api/metric` code layout. (#724)
+
+## [0.5.0] - 2020-05-13
+
+### Added
+
+- Batch `Observer` callback support. (#717)
+- Alias `api` types to root package of project. (#696)
+- Create basic `othttp.Transport` for simple client instrumentation. (#678)
+- `SetAttribute(string, interface{})` to the trace API. (#674)
+- Jaeger exporter option that allows user to specify custom http client. (#671)
+- `Stringer` and `Infer` methods to `key`s. (#662)
+
+### Changed
+
+- Rename `NewKey` in the `kv` package to just `Key`. (#721)
+- Move `core` and `key` to `kv` package. (#720)
+- Make the metric API `Meter` a `struct` so the abstract `MeterImpl` can be passed and simplify implementation. (#709)
+- Rename SDK `Batcher` to `Integrator` to match draft OpenTelemetry SDK specification. (#710)
+- Rename SDK `Ungrouped` integrator to `simple.Integrator` to match draft OpenTelemetry SDK specification. (#710)
+- Rename SDK `SDK` `struct` to `Accumulator` to match draft OpenTelemetry SDK specification. (#710)
+- Move `Number` from `core` to `api/metric` package. (#706)
+- Move `SpanContext` from `core` to `trace` package. (#692)
+- Change traceparent header from `Traceparent` to `traceparent` to implement the W3C specification. (#681)
+
+### Fixed
+
+- Update tooling to run generators in all submodules. (#705)
+- gRPC interceptor regexp to match methods without a service name. (#683)
+- Use a `const` for padding 64-bit B3 trace IDs. (#701)
+- Update `mockZipkin` listen address from `:0` to `127.0.0.1:0`. (#700)
+- Left-pad 64-bit B3 trace IDs with zero. (#698)
+- Propagate at least the first W3C tracestate header. (#694)
+- Remove internal `StateLocker` implementation. (#688)
+- Increase instance size CI system uses. (#690)
+- Add a `key` benchmark and use reflection in `key.Infer()`. (#679)
+- Fix internal `global` test by using `global.Meter` with `RecordBatch()`. (#680)
+- Reimplement histogram using mutex instead of `StateLocker`. (#669)
+- Switch `MinMaxSumCount` to a mutex lock implementation instead of `StateLocker`. (#667)
+- Update documentation to not include any references to `WithKeys`. (#672)
+- Correct misspelling. (#668)
+- Fix clobbering of the span context if extraction fails. (#656)
+- Bump `golangci-lint` and work around the corrupting bug. (#666) (#670)
+
+## [0.4.3] - 2020-04-24
+
+### Added
+
+- `Dockerfile` and `docker-compose.yml` to run example code. (#635)
+- New `grpctrace` package that provides gRPC client and server interceptors for both unary and stream connections. (#621)
+- New `api/label` package, providing common label set implementation. (#651)
+- Support for JSON marshaling of `Resources`. (#654)
+- `TraceID` and `SpanID` implementations for `Stringer` interface. (#642)
+- `RemoteAddrKey` in the othttp plugin to include the HTTP client address in top-level spans. (#627)
+- `WithSpanFormatter` option to the othttp plugin. (#617)
+- Updated README to include section for compatible libraries and include reference to the contrib repository. (#612)
+- The prometheus exporter now supports exporting histograms. (#601)
+- A `String` method to the `Resource` to return a hashable identifier for a now unique resource. (#613)
+- An `Iter` method to the `Resource` to return an array `AttributeIterator`. (#613)
+- An `Equal` method to the `Resource` test the equivalence of resources. (#613)
+- An iterable structure (`AttributeIterator`) for `Resource` attributes.
+
+### Changed
+
+- zipkin export's `NewExporter` now requires a `serviceName` argument to ensure this needed values is provided. (#644)
+- Pass `Resources` through the metrics export pipeline. (#659)
+
+### Removed
+
+- `WithKeys` option from the metric API. (#639)
+
+### Fixed
+
+- Use the `label.Set.Equivalent` value instead of an encoding in the batcher. (#658)
+- Correct typo `trace.Exporter` to `trace.SpanSyncer` in comments. (#653)
+- Use type names for return values in jaeger exporter. (#648)
+- Increase the visibility of the `api/key` package by updating comments and fixing usages locally. (#650)
+- `Checkpoint` only after `Update`; Keep records in the `sync.Map` longer. (#647)
+- Do not cache `reflect.ValueOf()` in metric Labels. (#649)
+- Batch metrics exported from the OTLP exporter based on `Resource` and labels. (#626)
+- Add error wrapping to the prometheus exporter. (#631)
+- Update the OTLP exporter batching of traces to use a unique `string` representation of an associated `Resource` as the batching key. (#623)
+- Update OTLP `SpanData` transform to only include the `ParentSpanID` if one exists. (#614)
+- Update `Resource` internal representation to uniquely and reliably identify resources. (#613)
+- Check return value from `CheckpointSet.ForEach` in prometheus exporter. (#622)
+- Ensure spans created by httptrace client tracer reflect operation structure. (#618)
+- Create a new recorder rather than reuse when multiple observations in same epoch for asynchronous instruments. #610
+- The default port the OTLP exporter uses to connect to the OpenTelemetry collector is updated to match the one the collector listens on by default. (#611)
+
+## [0.4.2] - 2020-03-31
+
+### Fixed
+
+- Fix `pre_release.sh` to update version in `sdk/opentelemetry.go`. (#607)
+- Fix time conversion from internal to OTLP in OTLP exporter. (#606)
+
+## [0.4.1] - 2020-03-31
+
+### Fixed
+
+- Update `tag.sh` to create signed tags. (#604)
+
+## [0.4.0] - 2020-03-30
+
+### Added
+
+- New API package `api/metric/registry` that exposes a `MeterImpl` wrapper for use by SDKs to generate unique instruments. (#580)
+- Script to verify examples after a new release. (#579)
+
+### Removed
+
+- The dogstatsd exporter due to lack of support.
+   This additionally removes support for statsd. (#591)
+- `LabelSet` from the metric API.
+   This is replaced by a `[]core.KeyValue` slice. (#595)
+- `Labels` from the metric API's `Meter` interface. (#595)
+
+### Changed
+
+- The metric `export.Labels` became an interface which the SDK implements and the `export` package provides a simple, immutable implementation of this interface intended for testing purposes. (#574)
+- Renamed `internal/metric.Meter` to `MeterImpl`. (#580)
+- Renamed `api/global/internal.obsImpl` to `asyncImpl`. (#580)
+
+### Fixed
+
+- Corrected missing return in mock span. (#582)
+- Update License header for all source files to match CNCF guidelines and include a test to ensure it is present. (#586) (#596)
+- Update to v0.3.0 of the OTLP in the OTLP exporter. (#588)
+- Update pre-release script to be compatible between GNU and BSD based systems. (#592)
+- Add a `RecordBatch` benchmark. (#594)
+- Moved span transforms of the OTLP exporter to the internal package. (#593)
+- Build both go-1.13 and go-1.14 in circleci to test for all supported versions of Go. (#569)
+- Removed unneeded allocation on empty labels in OLTP exporter. (#597)
+- Update `BatchedSpanProcessor` to process the queue until no data but respect max batch size. (#599)
+- Update project documentation godoc.org links to pkg.go.dev. (#602)
+
+## [0.3.0] - 2020-03-21
+
+This is a first official beta release, which provides almost fully complete metrics, tracing, and context propagation functionality.
+There is still a possibility of breaking changes.
+
+### Added
+
+- Add `Observer` metric instrument. (#474)
+- Add global `Propagators` functionality to enable deferred initialization for propagators registered before the first Meter SDK is installed. (#494)
+- Simplified export setup pipeline for the jaeger exporter to match other exporters. (#459)
+- The zipkin trace exporter. (#495)
+- The OTLP exporter to export metric and trace telemetry to the OpenTelemetry collector. (#497) (#544) (#545)
+- Add `StatusMessage` field to the trace `Span`. (#524)
+- Context propagation in OpenTracing bridge in terms of OpenTelemetry context propagation. (#525)
+- The `Resource` type was added to the SDK. (#528)
+- The global API now supports a `Tracer` and `Meter` function as shortcuts to getting a global `*Provider` and calling these methods directly. (#538)
+- The metric API now defines a generic `MeterImpl` interface to support general purpose `Meter` construction.
+   Additionally, `SyncImpl` and `AsyncImpl` are added to support general purpose instrument construction. (#560)
+- A metric `Kind` is added to represent the `MeasureKind`, `ObserverKind`, and `CounterKind`. (#560)
+- Scripts to better automate the release process. (#576)
+
+### Changed
+
+- Default to to use `AlwaysSampler` instead of `ProbabilitySampler` to match OpenTelemetry specification. (#506)
+- Renamed `AlwaysSampleSampler` to `AlwaysOnSampler` in the trace API. (#511)
+- Renamed `NeverSampleSampler` to `AlwaysOffSampler` in the trace API. (#511)
+- The `Status` field of the `Span` was changed to `StatusCode` to disambiguate with the added `StatusMessage`. (#524)
+- Updated the trace `Sampler` interface conform to the OpenTelemetry specification. (#531)
+- Rename metric API `Options` to `Config`. (#541)
+- Rename metric `Counter` aggregator to be `Sum`. (#541)
+- Unify metric options into `Option` from instrument specific options. (#541)
+- The trace API's `TraceProvider` now support `Resource`s. (#545)
+- Correct error in zipkin module name. (#548)
+- The jaeger trace exporter now supports `Resource`s. (#551)
+- Metric SDK now supports `Resource`s.
+   The `WithResource` option was added to configure a `Resource` on creation and the `Resource` method was added to the metric `Descriptor` to return the associated `Resource`. (#552)
+- Replace `ErrNoLastValue` and `ErrEmptyDataSet` by `ErrNoData` in the metric SDK. (#557)
+- The stdout trace exporter now supports `Resource`s. (#558)
+- The metric `Descriptor` is now included at the API instead of the SDK. (#560)
+- Replace `Ordered` with an iterator in `export.Labels`. (#567)
+
+### Removed
+
+- The vendor specific Stackdriver. It is now hosted on 3rd party vendor infrastructure. (#452)
+- The `Unregister` method for metric observers as it is not in the OpenTelemetry specification. (#560)
+- `GetDescriptor` from the metric SDK. (#575)
+- The `Gauge` instrument from the metric API. (#537)
+
+### Fixed
+
+- Make histogram aggregator checkpoint consistent. (#438)
+- Update README with import instructions and how to build and test. (#505)
+- The default label encoding was updated to be unique. (#508)
+- Use `NewRoot` in the othttp plugin for public endpoints. (#513)
+- Fix data race in `BatchedSpanProcessor`. (#518)
+- Skip test-386 for Mac OS 10.15.x (Catalina and upwards). #521
+- Use a variable-size array to represent ordered labels in maps. (#523)
+- Update the OTLP protobuf and update changed import path. (#532)
+- Use `StateLocker` implementation in `MinMaxSumCount`. (#546)
+- Eliminate goroutine leak in histogram stress test. (#547)
+- Update OTLP exporter with latest protobuf. (#550)
+- Add filters to the othttp plugin. (#556)
+- Provide an implementation of the `Header*` filters that do not depend on Go 1.14. (#565)
+- Encode labels once during checkpoint.
+   The checkpoint function is executed in a single thread so we can do the encoding lazily before passing the encoded version of labels to the exporter.
+   This is a cheap and quick way to avoid encoding the labels on every collection interval. (#572)
+- Run coverage over all packages in `COVERAGE_MOD_DIR`. (#573)
+
+## [0.2.3] - 2020-03-04
+
+### Added
+
+- `RecordError` method on `Span`s in the trace API to Simplify adding error events to spans. (#473)
+- Configurable push frequency for exporters setup pipeline. (#504)
+
+### Changed
+
+- Rename the `exporter` directory to `exporters`.
+   The `go.opentelemetry.io/otel/exporter/trace/jaeger` package was mistakenly released with a `v1.0.0` tag instead of `v0.1.0`.
+   This resulted in all subsequent releases not becoming the default latest.
+   A consequence of this was that all `go get`s pulled in the incompatible `v0.1.0` release of that package when pulling in more recent packages from other otel packages.
+   Renaming the `exporter` directory to `exporters` fixes this issue by renaming the package and therefore clearing any existing dependency tags.
+   Consequentially, this action also renames *all* exporter packages. (#502)
+
+### Removed
+
+- The `CorrelationContextHeader` constant in the `correlation` package is no longer exported. (#503)
+
+## [0.2.2] - 2020-02-27
+
+### Added
+
+- `HTTPSupplier` interface in the propagation API to specify methods to retrieve and store a single value for a key to be associated with a carrier. (#467)
+- `HTTPExtractor` interface in the propagation API to extract information from an `HTTPSupplier` into a context. (#467)
+- `HTTPInjector` interface in the propagation API to inject information into an `HTTPSupplier.` (#467)
+- `Config` and configuring `Option` to the propagator API. (#467)
+- `Propagators` interface in the propagation API to contain the set of injectors and extractors for all supported carrier formats. (#467)
+- `HTTPPropagator` interface in the propagation API to inject and extract from an `HTTPSupplier.` (#467)
+- `WithInjectors` and `WithExtractors` functions to the propagator API to configure injectors and extractors to use. (#467)
+- `ExtractHTTP` and `InjectHTTP` functions to apply configured HTTP extractors and injectors to a passed context. (#467)
+- Histogram aggregator. (#433)
+- `DefaultPropagator` function and have it return `trace.TraceContext` as the default context propagator. (#456)
+- `AlwaysParentSample` sampler to the trace API. (#455)
+- `WithNewRoot` option function to the trace API to specify the created span should be considered a root span. (#451)
+
+### Changed
+
+- Renamed `WithMap` to `ContextWithMap` in the correlation package. (#481)
+- Renamed `FromContext` to `MapFromContext` in the correlation package. (#481)
+- Move correlation context propagation to correlation package. (#479)
+- Do not default to putting remote span context into links. (#480)
+- `Tracer.WithSpan` updated to accept `StartOptions`. (#472)
+- Renamed `MetricKind` to `Kind` to not stutter in the type usage. (#432)
+- Renamed the `export` package to `metric` to match directory structure. (#432)
+- Rename the `api/distributedcontext` package to `api/correlation`. (#444)
+- Rename the `api/propagators` package to `api/propagation`. (#444)
+- Move the propagators from the `propagators` package into the `trace` API package. (#444)
+- Update `Float64Gauge`, `Int64Gauge`, `Float64Counter`, `Int64Counter`, `Float64Measure`, and `Int64Measure` metric methods to use value receivers instead of pointers. (#462)
+- Moved all dependencies of tools package to a tools directory. (#466)
+
+### Removed
+
+- Binary propagators. (#467)
+- NOOP propagator. (#467)
+
+### Fixed
+
+- Upgraded `github.com/golangci/golangci-lint` from `v1.21.0` to `v1.23.6` in `tools/`. (#492)
+- Fix a possible nil-dereference crash (#478)
+- Correct comments for `InstallNewPipeline` in the stdout exporter. (#483)
+- Correct comments for `InstallNewPipeline` in the dogstatsd exporter. (#484)
+- Correct comments for `InstallNewPipeline` in the prometheus exporter. (#482)
+- Initialize `onError` based on `Config` in prometheus exporter. (#486)
+- Correct module name in prometheus exporter README. (#475)
+- Removed tracer name prefix from span names. (#430)
+- Fix `aggregator_test.go` import package comment. (#431)
+- Improved detail in stdout exporter. (#436)
+- Fix a dependency issue (generate target should depend on stringer, not lint target) in Makefile. (#442)
+- Reorders the Makefile targets within `precommit` target so we generate files and build the code before doing linting, so we can get much nicer errors about syntax errors from the compiler. (#442)
+- Reword function documentation in gRPC plugin. (#446)
+- Send the `span.kind` tag to Jaeger from the jaeger exporter. (#441)
+- Fix `metadataSupplier` in the jaeger exporter to overwrite the header if existing instead of appending to it. (#441)
+- Upgraded to Go 1.13 in CI. (#465)
+- Correct opentelemetry.io URL in trace SDK documentation. (#464)
+- Refactored reference counting logic in SDK determination of stale records. (#468)
+- Add call to `runtime.Gosched` in instrument `acquireHandle` logic to not block the collector. (#469)
+
+## [0.2.1.1] - 2020-01-13
+
+### Fixed
+
+- Use stateful batcher on Prometheus exporter fixing regresion introduced in #395. (#428)
+
+## [0.2.1] - 2020-01-08
+
+### Added
+
+- Global meter forwarding implementation.
+   This enables deferred initialization for metric instruments registered before the first Meter SDK is installed. (#392)
+- Global trace forwarding implementation.
+   This enables deferred initialization for tracers registered before the first Trace SDK is installed. (#406)
+- Standardize export pipeline creation in all exporters. (#395)
+- A testing, organization, and comments for 64-bit field alignment. (#418)
+- Script to tag all modules in the project. (#414)
+
+### Changed
+
+- Renamed `propagation` package to `propagators`. (#362)
+- Renamed `B3Propagator` propagator to `B3`. (#362)
+- Renamed `TextFormatPropagator` propagator to `TextFormat`. (#362)
+- Renamed `BinaryPropagator` propagator to `Binary`. (#362)
+- Renamed `BinaryFormatPropagator` propagator to `BinaryFormat`. (#362)
+- Renamed `NoopTextFormatPropagator` propagator to `NoopTextFormat`. (#362)
+- Renamed `TraceContextPropagator` propagator to `TraceContext`. (#362)
+- Renamed `SpanOption` to `StartOption` in the trace API. (#369)
+- Renamed `StartOptions` to `StartConfig` in the trace API. (#369)
+- Renamed `EndOptions` to `EndConfig` in the trace API. (#369)
+- `Number` now has a pointer receiver for its methods. (#375)
+- Renamed `CurrentSpan` to `SpanFromContext` in the trace API. (#379)
+- Renamed `SetCurrentSpan` to `ContextWithSpan` in the trace API. (#379)
+- Renamed `Message` in Event to `Name` in the trace API. (#389)
+- Prometheus exporter no longer aggregates metrics, instead it only exports them. (#385)
+- Renamed `HandleImpl` to `BoundInstrumentImpl` in the metric API. (#400)
+- Renamed `Float64CounterHandle` to `Float64CounterBoundInstrument` in the metric API. (#400)
+- Renamed `Int64CounterHandle` to `Int64CounterBoundInstrument` in the metric API. (#400)
+- Renamed `Float64GaugeHandle` to `Float64GaugeBoundInstrument` in the metric API. (#400)
+- Renamed `Int64GaugeHandle` to `Int64GaugeBoundInstrument` in the metric API. (#400)
+- Renamed `Float64MeasureHandle` to `Float64MeasureBoundInstrument` in the metric API. (#400)
+- Renamed `Int64MeasureHandle` to `Int64MeasureBoundInstrument` in the metric API. (#400)
+- Renamed `Release` method for bound instruments in the metric API to `Unbind`. (#400)
+- Renamed `AcquireHandle` method for bound instruments in the metric API to `Bind`. (#400)
+- Renamed the `File` option in the stdout exporter to `Writer`. (#404)
+- Renamed all `Options` to `Config` for all metric exports where this wasn't already the case.
+
+### Fixed
+
+- Aggregator import path corrected. (#421)
+- Correct links in README. (#368)
+- The README was updated to match latest code changes in its examples. (#374)
+- Don't capitalize error statements. (#375)
+- Fix ignored errors. (#375)
+- Fix ambiguous variable naming. (#375)
+- Removed unnecessary type casting. (#375)
+- Use named parameters. (#375)
+- Updated release schedule. (#378)
+- Correct http-stackdriver example module name. (#394)
+- Removed the `http.request` span in `httptrace` package. (#397)
+- Add comments in the metrics SDK (#399)
+- Initialize checkpoint when creating ddsketch aggregator to prevent panic when merging into a empty one. (#402) (#403)
+- Add documentation of compatible exporters in the README. (#405)
+- Typo fix. (#408)
+- Simplify span check logic in SDK tracer implementation. (#419)
+
+## [0.2.0] - 2019-12-03
+
+### Added
+
+- Unary gRPC tracing example. (#351)
+- Prometheus exporter. (#334)
+- Dogstatsd metrics exporter. (#326)
+
+### Changed
+
+- Rename `MaxSumCount` aggregation to `MinMaxSumCount` and add the `Min` interface for this aggregation. (#352)
+- Rename `GetMeter` to `Meter`. (#357)
+- Rename `HTTPTraceContextPropagator` to `TraceContextPropagator`. (#355)
+- Rename `HTTPB3Propagator` to `B3Propagator`. (#355)
+- Rename `HTTPTraceContextPropagator` to `TraceContextPropagator`. (#355)
+- Move `/global` package to `/api/global`. (#356)
+- Rename `GetTracer` to `Tracer`. (#347)
+
+### Removed
+
+- `SetAttribute` from the `Span` interface in the trace API. (#361)
+- `AddLink` from the `Span` interface in the trace API. (#349)
+- `Link` from the `Span` interface in the trace API. (#349)
+
+### Fixed
+
+- Exclude example directories from coverage report. (#365)
+- Lint make target now implements automatic fixes with `golangci-lint` before a second run to report the remaining issues. (#360)
+- Drop `GO111MODULE` environment variable in Makefile as Go 1.13 is the project specified minimum version and this is environment variable is not needed for that version of Go. (#359)
+- Run the race checker for all test. (#354)
+- Redundant commands in the Makefile are removed. (#354)
+- Split the `generate` and `lint` targets of the Makefile. (#354)
+- Renames `circle-ci` target to more generic `ci` in Makefile. (#354)
+- Add example Prometheus binary to gitignore. (#358)
+- Support negative numbers with the `MaxSumCount`. (#335)
+- Resolve race conditions in `push_test.go` identified in #339. (#340)
+- Use `/usr/bin/env bash` as a shebang in scripts rather than `/bin/bash`. (#336)
+- Trace benchmark now tests both `AlwaysSample` and `NeverSample`.
+   Previously it was testing `AlwaysSample` twice. (#325)
+- Trace benchmark now uses a `[]byte` for `TraceID` to fix failing test. (#325)
+- Added a trace benchmark to test variadic functions in `setAttribute` vs `setAttributes` (#325)
+- The `defaultkeys` batcher was only using the encoded label set as its map key while building a checkpoint.
+   This allowed distinct label sets through, but any metrics sharing a label set could be overwritten or merged incorrectly.
+   This was corrected. (#333)
+
+## [0.1.2] - 2019-11-18
+
+### Fixed
+
+- Optimized the `simplelru` map for attributes to reduce the number of allocations. (#328)
+- Removed unnecessary unslicing of parameters that are already a slice. (#324)
+
+## [0.1.1] - 2019-11-18
+
+This release contains a Metrics SDK with stdout exporter and supports basic aggregations such as counter, gauges, array, maxsumcount, and ddsketch.
+
+### Added
+
+- Metrics stdout export pipeline. (#265)
+- Array aggregation for raw measure metrics. (#282)
+- The core.Value now have a `MarshalJSON` method. (#281)
+
+### Removed
+
+- `WithService`, `WithResources`, and `WithComponent` methods of tracers. (#314)
+- Prefix slash in `Tracer.Start()` for the Jaeger example. (#292)
+
+### Changed
+
+- Allocation in LabelSet construction to reduce GC overhead. (#318)
+- `trace.WithAttributes` to append values instead of replacing (#315)
+- Use a formula for tolerance in sampling tests. (#298)
+- Move export types into trace and metric-specific sub-directories. (#289)
+- `SpanKind` back to being based on an `int` type. (#288)
+
+### Fixed
+
+- URL to OpenTelemetry website in README. (#323)
+- Name of othttp default tracer. (#321)
+- `ExportSpans` for the stackdriver exporter now handles `nil` context. (#294)
+- CI modules cache to correctly restore/save from/to the cache. (#316)
+- Fix metric SDK race condition between `LoadOrStore` and the assignment `rec.recorder = i.meter.exporter.AggregatorFor(rec)`. (#293)
+- README now reflects the new code structure introduced with these changes. (#291)
+- Make the basic example work. (#279)
+
+## [0.1.0] - 2019-11-04
+
+This is the first release of open-telemetry go library.
+It contains api and sdk for trace and meter.
+
+### Added
+
+- Initial OpenTelemetry trace and metric API prototypes.
+- Initial OpenTelemetry trace, metric, and export SDK packages.
+- A wireframe bridge to support compatibility with OpenTracing.
+- Example code for a basic, http-stackdriver, http, jaeger, and named tracer setup.
+- Exporters for Jaeger, Stackdriver, and stdout.
+- Propagators for binary, B3, and trace-context protocols.
+- Project information and guidelines in the form of a README and CONTRIBUTING.
+- Tools to build the project and a Makefile to automate the process.
+- Apache-2.0 license.
+- CircleCI build CI manifest files.
+- CODEOWNERS file to track owners of this project.
+
+[Unreleased]: https://github.com/open-telemetry/opentelemetry-go/compare/v1.9.0...HEAD
+[1.9.0/0.0.3]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.9.0
+[1.8.0/0.31.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.8.0
+[1.7.0/0.30.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.7.0
+[0.29.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/metric/v0.29.0
+[1.6.3]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.6.3
+[1.6.2]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.6.2
+[1.6.1]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.6.1
+[1.6.0/0.28.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.6.0
+[1.5.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.5.0
+[1.4.1]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.4.1
+[1.4.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.4.0
+[1.3.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.3.0
+[1.2.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.2.0
+[1.1.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.1.0
+[1.0.1]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.0.1
+[Metrics 0.24.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/metric/v0.24.0
+[1.0.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.0.0
+[1.0.0-RC3]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.0.0-RC3
+[1.0.0-RC2]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.0.0-RC2
+[Experimental Metrics v0.22.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/metric/v0.22.0
+[1.0.0-RC1]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v1.0.0-RC1
+[0.20.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.20.0
+[0.19.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.19.0
+[0.18.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.18.0
+[0.17.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.17.0
+[0.16.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.16.0
+[0.15.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.15.0
+[0.14.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.14.0
+[0.13.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.13.0
+[0.12.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.12.0
+[0.11.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.11.0
+[0.10.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.10.0
+[0.9.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.9.0
+[0.8.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.8.0
+[0.7.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.7.0
+[0.6.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.6.0
+[0.5.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.5.0
+[0.4.3]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.4.3
+[0.4.2]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.4.2
+[0.4.1]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.4.1
+[0.4.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.4.0
+[0.3.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.3.0
+[0.2.3]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.2.3
+[0.2.2]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.2.2
+[0.2.1.1]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.2.1.1
+[0.2.1]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.2.1
+[0.2.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.2.0
+[0.1.2]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.1.2
+[0.1.1]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.1.1
+[0.1.0]: https://github.com/open-telemetry/opentelemetry-go/releases/tag/v0.1.0

vendor/go.opentelemetry.io/otel/CODEOWNERS

+#####################################################
+#
+# List of approvers for this repository
+#
+#####################################################
+#
+# Learn about membership in OpenTelemetry community:
+#  https://github.com/open-telemetry/community/blob/main/community-membership.md
+#
+#
+# Learn about CODEOWNERS file format:
+#  https://help.github.com/en/articles/about-code-owners
+#
+
+* @jmacd @MrAlias @Aneurysm9 @evantorrie @XSAM @dashpole @MadVikingGod @pellared @hanyuancheung @dmathieu
+
+CODEOWNERS @MrAlias @Aneurysm9 @MadVikingGod

vendor/go.opentelemetry.io/otel/CONTRIBUTING.md

+# Contributing to opentelemetry-go
+
+The Go special interest group (SIG) meets regularly. See the
+OpenTelemetry
+[community](https://github.com/open-telemetry/community#golang-sdk)
+repo for information on this and other language SIGs.
+
+See the [public meeting
+notes](https://docs.google.com/document/d/1A63zSWX0x2CyCK_LoNhmQC4rqhLpYXJzXbEPDUQ2n6w/edit#heading=h.9tngw7jdwd6b)
+for a summary description of past meetings. To request edit access,
+join the meeting or get in touch on
+[Slack](https://cloud-native.slack.com/archives/C01NPAXACKT).
+
+## Development
+
+You can view and edit the source code by cloning this repository:
+
+```sh
+git clone https://github.com/open-telemetry/opentelemetry-go.git
+```
+
+Run `make test` to run the tests instead of `go test`.
+
+There are some generated files checked into the repo. To make sure
+that the generated files are up-to-date, run `make` (or `make
+precommit` - the `precommit` target is the default).
+
+The `precommit` target also fixes the formatting of the code and
+checks the status of the go module files.
+
+If after running `make precommit` the output of `git status` contains
+`nothing to commit, working tree clean` then it means that everything
+is up-to-date and properly formatted.
+
+## Pull Requests
+
+### How to Send Pull Requests
+
+Everyone is welcome to contribute code to `opentelemetry-go` via
+GitHub pull requests (PRs).
+
+To create a new PR, fork the project in GitHub and clone the upstream
+repo:
+
+```sh
+go get -d go.opentelemetry.io/otel
+```
+
+(This may print some warning about "build constraints exclude all Go
+files", just ignore it.)
+
+This will put the project in `${GOPATH}/src/go.opentelemetry.io/otel`. You
+can alternatively use `git` directly with:
+
+```sh
+git clone https://github.com/open-telemetry/opentelemetry-go
+```
+
+(Note that `git clone` is *not* using the `go.opentelemetry.io/otel` name -
+that name is a kind of a redirector to GitHub that `go get` can
+understand, but `git` does not.)
+
+This would put the project in the `opentelemetry-go` directory in
+current working directory.
+
+Enter the newly created directory and add your fork as a new remote:
+
+```sh
+git remote add <YOUR_FORK> git@github.com:<YOUR_GITHUB_USERNAME>/opentelemetry-go
+```
+
+Check out a new branch, make modifications, run linters and tests, update
+`CHANGELOG.md`, and push the branch to your fork:
+
+```sh
+git checkout -b <YOUR_BRANCH_NAME>
+# edit files
+# update changelog
+make precommit
+git add -p
+git commit
+git push <YOUR_FORK> <YOUR_BRANCH_NAME>
+```
+
+Open a pull request against the main `opentelemetry-go` repo. Be sure to add the pull
+request ID to the entry you added to `CHANGELOG.md`.
+
+### How to Receive Comments
+
+* If the PR is not ready for review, please put `[WIP]` in the title,
+  tag it as `work-in-progress`, or mark it as
+  [`draft`](https://github.blog/2019-02-14-introducing-draft-pull-requests/).
+* Make sure CLA is signed and CI is clear.
+
+### How to Get PRs Merged
+
+A PR is considered to be **ready to merge** when:
+
+* It has received two approvals from Collaborators/Maintainers (at
+  different companies). This is not enforced through technical means
+  and a PR may be **ready to merge** with a single approval if the change
+  and its approach have been discussed and consensus reached.
+* Feedback has been addressed.
+* Any substantive changes to your PR will require that you clear any prior
+  Approval reviews, this includes changes resulting from other feedback. Unless
+  the approver explicitly stated that their approval will persist across
+  changes it should be assumed that the PR needs their review again. Other
+  project members (e.g. approvers, maintainers) can help with this if there are
+  any questions or if you forget to clear reviews.
+* It has been open for review for at least one working day. This gives
+  people reasonable time to review.
+* Trivial changes (typo, cosmetic, doc, etc.) do not have to wait for
+  one day and may be merged with a single Maintainer's approval.
+* `CHANGELOG.md` has been updated to reflect what has been
+  added, changed, removed, or fixed.
+* `README.md` has been updated if necessary.
+* Urgent fix can take exception as long as it has been actively
+  communicated.
+
+Any Maintainer can merge the PR once it is **ready to merge**.
+
+## Design Choices
+
+As with other OpenTelemetry clients, opentelemetry-go follows the
+[opentelemetry-specification](https://github.com/open-telemetry/opentelemetry-specification).
+
+It's especially valuable to read through the [library
+guidelines](https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/library-guidelines.md).
+
+### Focus on Capabilities, Not Structure Compliance
+
+OpenTelemetry is an evolving specification, one where the desires and
+use cases are clear, but the method to satisfy those uses cases are
+not.
+
+As such, Contributions should provide functionality and behavior that
+conforms to the specification, but the interface and structure is
+flexible.
+
+It is preferable to have contributions follow the idioms of the
+language rather than conform to specific API names or argument
+patterns in the spec.
+
+For a deeper discussion, see
+[this](https://github.com/open-telemetry/opentelemetry-specification/issues/165).
+
+## Documentation
+
+Each non-example Go Module should have its own `README.md` containing:
+
+- A pkg.go.dev badge which can be generated [here](https://pkg.go.dev/badge/).
+- Brief description.
+- Installation instructions (and requirements if applicable).
+- Hyperlink to an example. Depending on the component the example can be:
+  - An `example_test.go` like [here](exporters/stdout/stdouttrace/example_test.go).
+  - A sample Go application with its own `README.md`, like [here](example/zipkin).
+- Additional documentation sections such us:
+  - Configuration,
+  - Contributing,
+  - References.
+
+[Here](exporters/jaeger/README.md) is an example of a concise `README.md`.
+
+Moreover, it should be possible to navigate to any `README.md` from the
+root `README.md`.
+
+## Style Guide
+
+One of the primary goals of this project is that it is actually used by
+developers. With this goal in mind the project strives to build
+user-friendly and idiomatic Go code adhering to the Go community's best
+practices.
+
+For a non-comprehensive but foundational overview of these best practices
+the [Effective Go](https://golang.org/doc/effective_go.html) documentation
+is an excellent starting place.
+
+As a convenience for developers building this project the `make precommit`
+will format, lint, validate, and in some cases fix the changes you plan to
+submit. This check will need to pass for your changes to be able to be
+merged.
+
+In addition to idiomatic Go, the project has adopted certain standards for
+implementations of common patterns. These standards should be followed as a
+default, and if they are not followed documentation needs to be included as
+to the reasons why.
+
+### Configuration
+
+When creating an instantiation function for a complex `type T struct`, it is
+useful to allow variable number of options to be applied. However, the strong
+type system of Go restricts the function design options. There are a few ways
+to solve this problem, but we have landed on the following design.
+
+#### `config`
+
+Configuration should be held in a `struct` named `config`, or prefixed with
+specific type name this Configuration applies to if there are multiple
+`config` in the package. This type must contain configuration options.
+
+```go
+// config contains configuration options for a thing.
+type config struct {
+	// options ...
+}
+```
+
+In general the `config` type will not need to be used externally to the
+package and should be unexported. If, however, it is expected that the user
+will likely want to build custom options for the configuration, the `config`
+should be exported. Please, include in the documentation for the `config`
+how the user can extend the configuration.
+
+It is important that internal `config` are not shared across package boundaries.
+Meaning a `config` from one package should not be directly used by another. The
+one exception is the API packages.  The configs from the base API, eg.
+`go.opentelemetry.io/otel/trace.TracerConfig` and
+`go.opentelemetry.io/otel/metric.InstrumentConfig`, are intended to be consumed
+by the SDK therefor it is expected that these are exported.
+
+When a config is exported we want to maintain forward and backward
+compatibility, to achieve this no fields should be exported but should
+instead be accessed by methods.
+
+Optionally, it is common to include a `newConfig` function (with the same
+naming scheme). This function wraps any defaults setting and looping over
+all options to create a configured `config`.
+
+```go
+// newConfig returns an appropriately configured config.
+func newConfig(options ...Option) config {
+	// Set default values for config.
+	config := config{/* […] */}
+	for _, option := range options {
+		config = option.apply(config)
+	}
+	// Preform any validation here.
+	return config
+}
+```
+
+If validation of the `config` options is also preformed this can return an
+error as well that is expected to be handled by the instantiation function
+or propagated to the user.
+
+Given the design goal of not having the user need to work with the `config`,
+the `newConfig` function should also be unexported.
+
+#### `Option`
+
+To set the value of the options a `config` contains, a corresponding
+`Option` interface type should be used.
+
+```go
+type Option interface {
+	apply(config) config
+}
+```
+
+Having `apply` unexported makes sure that it will not be used externally.
+Moreover, the interface becomes sealed so the user cannot easily implement
+the interface on its own.
+
+The `apply` method should return a modified version of the passed config.
+This approach, instead of passing a pointer, is used to prevent the config from being allocated to the heap.
+
+The name of the interface should be prefixed in the same way the
+corresponding `config` is (if at all).
+
+#### Options
+
+All user configurable options for a `config` must have a related unexported
+implementation of the `Option` interface and an exported configuration
+function that wraps this implementation.
+
+The wrapping function name should be prefixed with `With*` (or in the
+special case of a boolean options `Without*`) and should have the following
+function signature.
+
+```go
+func With*(…) Option { … }
+```
+
+##### `bool` Options
+
+```go
+type defaultFalseOption bool
+
+func (o defaultFalseOption) apply(c config) config {
+	c.Bool = bool(o)
+    return c
+}
+
+// WithOption sets a T to have an option included.
+func WithOption() Option {
+	return defaultFalseOption(true)
+}
+```
+
+```go
+type defaultTrueOption bool
+
+func (o defaultTrueOption) apply(c config) config {
+	c.Bool = bool(o)
+    return c
+}
+
+// WithoutOption sets a T to have Bool option excluded.
+func WithoutOption() Option {
+	return defaultTrueOption(false)
+}
+```
+
+##### Declared Type Options
+
+```go
+type myTypeOption struct {
+	MyType MyType
+}
+
+func (o myTypeOption) apply(c config) config {
+	c.MyType = o.MyType
+    return c
+}
+
+// WithMyType sets T to have include MyType.
+func WithMyType(t MyType) Option {
+	return myTypeOption{t}
+}
+```
+
+##### Functional Options
+
+```go
+type optionFunc func(config) config
+
+func (fn optionFunc) apply(c config) config {
+	return fn(c)
+}
+
+// WithMyType sets t as MyType.
+func WithMyType(t MyType) Option {
+	return optionFunc(func(c config) config {
+		c.MyType = t
+        return c
+	})
+}
+```
+
+#### Instantiation
+
+Using this configuration pattern to configure instantiation with a `NewT`
+function.
+
+```go
+func NewT(options ...Option) T {…}
+```
+
+Any required parameters can be declared before the variadic `options`.
+
+#### Dealing with Overlap
+
+Sometimes there are multiple complex `struct` that share common
+configuration and also have distinct configuration. To avoid repeated
+portions of `config`s, a common `config` can be used with the union of
+options being handled with the `Option` interface.
+
+For example.
+
+```go
+// config holds options for all animals.
+type config struct {
+	Weight      float64
+	Color       string
+	MaxAltitude float64
+}
+
+// DogOption apply Dog specific options.
+type DogOption interface {
+	applyDog(config) config
+}
+
+// BirdOption apply Bird specific options.
+type BirdOption interface {
+	applyBird(config) config
+}
+
+// Option apply options for all animals.
+type Option interface {
+	BirdOption
+	DogOption
+}
+
+type weightOption float64
+
+func (o weightOption) applyDog(c config) config {
+	c.Weight = float64(o)
+	return c
+}
+
+func (o weightOption) applyBird(c config) config {
+	c.Weight = float64(o)
+	return c
+}
+
+func WithWeight(w float64) Option { return weightOption(w) }
+
+type furColorOption string
+
+func (o furColorOption) applyDog(c config) config {
+	c.Color = string(o)
+	return c
+}
+
+func WithFurColor(c string) DogOption { return furColorOption(c) }
+
+type maxAltitudeOption float64
+
+func (o maxAltitudeOption) applyBird(c config) config {
+	c.MaxAltitude = float64(o)
+	return c
+}
+
+func WithMaxAltitude(a float64) BirdOption { return maxAltitudeOption(a) }
+
+func NewDog(name string, o ...DogOption) Dog    {…}
+func NewBird(name string, o ...BirdOption) Bird {…}
+```
+
+### Interfaces
+
+To allow other developers to better comprehend the code, it is important
+to ensure it is sufficiently documented. One simple measure that contributes
+to this aim is self-documenting by naming method parameters. Therefore,
+where appropriate, methods of every exported interface type should have
+their parameters appropriately named.
+
+#### Interface Stability
+
+All exported stable interfaces that include the following warning in their
+doumentation are allowed to be extended with additional methods.
+
+> Warning: methods may be added to this interface in minor releases.
+
+Otherwise, stable interfaces MUST NOT be modified.
+
+If new functionality is needed for an interface that cannot be changed it MUST
+be added by including an additional interface. That added interface can be a
+simple interface for the specific functionality that you want to add or it can
+be a super-set of the original interface. For example, if you wanted to a
+`Close` method to the `Exporter` interface:
+
+```go
+type Exporter interface {
+	Export()
+}
+```
+
+A new interface, `Closer`, can be added:
+
+```go
+type Closer interface {
+	Close()
+}
+```
+
+Code that is passed the `Exporter` interface can now check to see if the passed
+value also satisfies the new interface. E.g.
+
+```go
+func caller(e Exporter) {
+	/* ... */
+	if c, ok := e.(Closer); ok {
+		c.Close()
+	}
+	/* ... */
+}
+```
+
+Alternatively, a new type that is the super-set of an `Exporter` can be created.
+
+```go
+type ClosingExporter struct {
+	Exporter
+	Close()
+}
+```
+
+This new type can be used similar to the simple interface above in that a
+passed `Exporter` type can be asserted to satisfy the `ClosingExporter` type
+and the `Close` method called.
+
+This super-set approach can be useful if there is explicit behavior that needs
+to be coupled with the original type and passed as a unified type to a new
+function, but, because of this coupling, it also limits the applicability of
+the added functionality. If there exist other interfaces where this
+functionality should be added, each one will need their own super-set
+interfaces and will duplicate the pattern. For this reason, the simple targeted
+interface that defines the specific functionality should be preferred.
+
+## Approvers and Maintainers
+
+Approvers:
+
+- [Evan Torrie](https://github.com/evantorrie), Verizon Media
+- [Josh MacDonald](https://github.com/jmacd), LightStep
+- [Sam Xie](https://github.com/XSAM), Cisco/AppDynamics
+- [David Ashpole](https://github.com/dashpole), Google
+- [Robert Pająk](https://github.com/pellared), Splunk
+- [Chester Cheung](https://github.com/hanyuancheung), Tencent
+- [Damien Mathieu](https://github.com/dmathieu), Auth0/Okta
+
+Maintainers:
+
+- [Aaron Clawson](https://github.com/MadVikingGod), LightStep
+- [Anthony Mirabella](https://github.com/Aneurysm9), AWS
+- [Tyler Yahn](https://github.com/MrAlias), Splunk
+
+Emeritus:
+
+- [Gustavo Silva Paiva](https://github.com/paivagustavo), LightStep
+
+### Become an Approver or a Maintainer
+
+See the [community membership document in OpenTelemetry community
+repo](https://github.com/open-telemetry/community/blob/main/community-membership.md).

vendor/go.opentelemetry.io/otel/LICENSE

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vendor/go.opentelemetry.io/otel/Makefile

+# Copyright The OpenTelemetry Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+TOOLS_MOD_DIR := ./internal/tools
+
+ALL_DOCS := $(shell find . -name '*.md' -type f | sort)
+ALL_GO_MOD_DIRS := $(shell find . -type f -name 'go.mod' -exec dirname {} \; | sort)
+OTEL_GO_MOD_DIRS := $(filter-out $(TOOLS_MOD_DIR), $(ALL_GO_MOD_DIRS))
+ALL_COVERAGE_MOD_DIRS := $(shell find . -type f -name 'go.mod' -exec dirname {} \; | egrep -v '^./example|^$(TOOLS_MOD_DIR)' | sort)
+
+GO = go
+TIMEOUT = 60
+
+.DEFAULT_GOAL := precommit
+
+.PHONY: precommit ci
+precommit: dependabot-generate license-check vanity-import-fix misspell go-mod-tidy golangci-lint-fix test-default
+ci: dependabot-check license-check lint vanity-import-check build test-default check-clean-work-tree test-coverage
+
+# Tools
+
+TOOLS = $(CURDIR)/.tools
+
+$(TOOLS):
+	@mkdir -p $@
+$(TOOLS)/%: | $(TOOLS)
+	cd $(TOOLS_MOD_DIR) && \
+	$(GO) build -o $@ $(PACKAGE)
+
+MULTIMOD = $(TOOLS)/multimod
+$(TOOLS)/multimod: PACKAGE=go.opentelemetry.io/build-tools/multimod
+
+SEMCONVGEN = $(TOOLS)/semconvgen
+$(TOOLS)/semconvgen: PACKAGE=go.opentelemetry.io/build-tools/semconvgen
+
+CROSSLINK = $(TOOLS)/crosslink
+$(TOOLS)/crosslink: PACKAGE=go.opentelemetry.io/build-tools/crosslink
+
+SEMCONVKIT = $(TOOLS)/semconvkit
+$(TOOLS)/semconvkit: PACKAGE=go.opentelemetry.io/otel/$(TOOLS_MOD_DIR)/semconvkit
+
+DBOTCONF = $(TOOLS)/dbotconf
+$(TOOLS)/dbotconf: PACKAGE=go.opentelemetry.io/build-tools/dbotconf
+
+GOLANGCI_LINT = $(TOOLS)/golangci-lint
+$(TOOLS)/golangci-lint: PACKAGE=github.com/golangci/golangci-lint/cmd/golangci-lint
+
+MISSPELL = $(TOOLS)/misspell
+$(TOOLS)/misspell: PACKAGE=github.com/client9/misspell/cmd/misspell
+
+GOCOVMERGE = $(TOOLS)/gocovmerge
+$(TOOLS)/gocovmerge: PACKAGE=github.com/wadey/gocovmerge
+
+STRINGER = $(TOOLS)/stringer
+$(TOOLS)/stringer: PACKAGE=golang.org/x/tools/cmd/stringer
+
+PORTO = $(TOOLS)/porto
+$(TOOLS)/porto: PACKAGE=github.com/jcchavezs/porto/cmd/porto
+
+GOJQ = $(TOOLS)/gojq
+$(TOOLS)/gojq: PACKAGE=github.com/itchyny/gojq/cmd/gojq
+
+.PHONY: tools
+tools: $(CROSSLINK) $(DBOTCONF) $(GOLANGCI_LINT) $(MISSPELL) $(GOCOVMERGE) $(STRINGER) $(PORTO) $(GOJQ) $(SEMCONVGEN) $(MULTIMOD) $(SEMCONVKIT)
+
+# Build
+
+.PHONY: generate build
+
+generate: $(OTEL_GO_MOD_DIRS:%=generate/%)
+generate/%: DIR=$*
+generate/%: | $(STRINGER) $(PORTO)
+	@echo "$(GO) generate $(DIR)/..." \
+		&& cd $(DIR) \
+		&& PATH="$(TOOLS):$${PATH}" $(GO) generate ./... && $(PORTO) -w .
+
+build: generate $(OTEL_GO_MOD_DIRS:%=build/%) $(OTEL_GO_MOD_DIRS:%=build-tests/%)
+build/%: DIR=$*
+build/%:
+	@echo "$(GO) build $(DIR)/..." \
+		&& cd $(DIR) \
+		&& $(GO) build ./...
+
+build-tests/%: DIR=$*
+build-tests/%:
+	@echo "$(GO) build tests $(DIR)/..." \
+		&& cd $(DIR) \
+		&& $(GO) list ./... \
+		| grep -v third_party \
+		| xargs $(GO) test -vet=off -run xxxxxMatchNothingxxxxx >/dev/null
+
+# Tests
+
+TEST_TARGETS := test-default test-bench test-short test-verbose test-race
+.PHONY: $(TEST_TARGETS) test
+test-default test-race: ARGS=-race
+test-bench:   ARGS=-run=xxxxxMatchNothingxxxxx -test.benchtime=1ms -bench=.
+test-short:   ARGS=-short
+test-verbose: ARGS=-v -race
+$(TEST_TARGETS): test
+test: $(OTEL_GO_MOD_DIRS:%=test/%)
+test/%: DIR=$*
+test/%:
+	@echo "$(GO) test -timeout $(TIMEOUT)s $(ARGS) $(DIR)/..." \
+		&& cd $(DIR) \
+		&& $(GO) list ./... \
+		| grep -v third_party \
+		| xargs $(GO) test -timeout $(TIMEOUT)s $(ARGS)
+
+COVERAGE_MODE    = atomic
+COVERAGE_PROFILE = coverage.out
+.PHONY: test-coverage
+test-coverage: | $(GOCOVMERGE)
+	@set -e; \
+	printf "" > coverage.txt; \
+	for dir in $(ALL_COVERAGE_MOD_DIRS); do \
+	  echo "$(GO) test -coverpkg=go.opentelemetry.io/otel/... -covermode=$(COVERAGE_MODE) -coverprofile="$(COVERAGE_PROFILE)" $${dir}/..."; \
+	  (cd "$${dir}" && \
+	    $(GO) list ./... \
+	    | grep -v third_party \
+	    | grep -v 'semconv/v.*' \
+	    | xargs $(GO) test -coverpkg=./... -covermode=$(COVERAGE_MODE) -coverprofile="$(COVERAGE_PROFILE)" && \
+	  $(GO) tool cover -html=coverage.out -o coverage.html); \
+	done; \
+	$(GOCOVMERGE) $$(find . -name coverage.out) > coverage.txt
+
+.PHONY: golangci-lint golangci-lint-fix
+golangci-lint-fix: ARGS=--fix
+golangci-lint-fix: golangci-lint
+golangci-lint: $(OTEL_GO_MOD_DIRS:%=golangci-lint/%)
+golangci-lint/%: DIR=$*
+golangci-lint/%: | $(GOLANGCI_LINT)
+	@echo 'golangci-lint $(if $(ARGS),$(ARGS) ,)$(DIR)' \
+		&& cd $(DIR) \
+		&& $(GOLANGCI_LINT) run --allow-serial-runners $(ARGS)
+
+.PHONY: crosslink
+crosslink: | $(CROSSLINK)
+	@echo "Updating intra-repository dependencies in all go modules" \
+		&& $(CROSSLINK) --root=$(shell pwd) --prune
+
+.PHONY: go-mod-tidy
+go-mod-tidy: $(ALL_GO_MOD_DIRS:%=go-mod-tidy/%)
+go-mod-tidy/%: DIR=$*
+go-mod-tidy/%: | crosslink
+	@echo "$(GO) mod tidy in $(DIR)" \
+		&& cd $(DIR) \
+		&& $(GO) mod tidy -compat=1.17
+
+.PHONY: lint-modules
+lint-modules: go-mod-tidy
+
+.PHONY: lint
+lint: misspell lint-modules golangci-lint
+
+.PHONY: vanity-import-check
+vanity-import-check: | $(PORTO)
+	@$(PORTO) --include-internal -l . || echo "(run: make vanity-import-fix)"
+
+.PHONY: vanity-import-fix
+vanity-import-fix: | $(PORTO)
+	@$(PORTO) --include-internal -w .
+
+.PHONY: misspell
+misspell: | $(MISSPELL)
+	@$(MISSPELL) -w $(ALL_DOCS)
+
+.PHONY: license-check
+license-check:
+	@licRes=$$(for f in $$(find . -type f \( -iname '*.go' -o -iname '*.sh' \) ! -path '**/third_party/*' ! -path './.git/*' ) ; do \
+	           awk '/Copyright The OpenTelemetry Authors|generated|GENERATED/ && NR<=3 { found=1; next } END { if (!found) print FILENAME }' $$f; \
+	   done); \
+	   if [ -n "$${licRes}" ]; then \
+	           echo "license header checking failed:"; echo "$${licRes}"; \
+	           exit 1; \
+	   fi
+
+DEPENDABOT_CONFIG = .github/dependabot.yml
+.PHONY: dependabot-check
+dependabot-check: | $(DBOTCONF)
+	@$(DBOTCONF) verify $(DEPENDABOT_CONFIG) || echo "(run: make dependabot-generate)"
+
+.PHONY: dependabot-generate
+dependabot-generate: | $(DBOTCONF)
+	@$(DBOTCONF) generate > $(DEPENDABOT_CONFIG)
+
+.PHONY: check-clean-work-tree
+check-clean-work-tree:
+	@if ! git diff --quiet; then \
+	  echo; \
+	  echo 'Working tree is not clean, did you forget to run "make precommit"?'; \
+	  echo; \
+	  git status; \
+	  exit 1; \
+	fi
+
+SEMCONVPKG ?= "semconv/"
+.PHONY: semconv-generate
+semconv-generate: | $(SEMCONVGEN) $(SEMCONVKIT)
+	@[ "$(TAG)" ] || ( echo "TAG unset: missing opentelemetry specification tag"; exit 1 )
+	@[ "$(OTEL_SPEC_REPO)" ] || ( echo "OTEL_SPEC_REPO unset: missing path to opentelemetry specification repo"; exit 1 )
+	@$(SEMCONVGEN) -i "$(OTEL_SPEC_REPO)/semantic_conventions/trace" -t "$(SEMCONVPKG)/template.j2" -s "$(TAG)"
+	@$(SEMCONVGEN) -i "$(OTEL_SPEC_REPO)/semantic_conventions/resource" -t "$(SEMCONVPKG)/template.j2" -s "$(TAG)"
+	@$(SEMCONVKIT) -output "$(SEMCONVPKG)/$(TAG)" -tag "$(TAG)"
+
+.PHONY: prerelease
+prerelease: | $(MULTIMOD)
+	@[ "${MODSET}" ] || ( echo ">> env var MODSET is not set"; exit 1 )
+	$(MULTIMOD) verify && $(MULTIMOD) prerelease -m ${MODSET}
+
+COMMIT ?= "HEAD"
+.PHONY: add-tags
+add-tags: | $(MULTIMOD)
+	@[ "${MODSET}" ] || ( echo ">> env var MODSET is not set"; exit 1 )
+	$(MULTIMOD) verify && $(MULTIMOD) tag -m ${MODSET} -c ${COMMIT}

vendor/go.opentelemetry.io/otel/README.md

+# OpenTelemetry-Go
+
+[![CI](https://github.com/open-telemetry/opentelemetry-go/workflows/ci/badge.svg)](https://github.com/open-telemetry/opentelemetry-go/actions?query=workflow%3Aci+branch%3Amain)
+[![codecov.io](https://codecov.io/gh/open-telemetry/opentelemetry-go/coverage.svg?branch=main)](https://app.codecov.io/gh/open-telemetry/opentelemetry-go?branch=main)
+[![PkgGoDev](https://pkg.go.dev/badge/go.opentelemetry.io/otel)](https://pkg.go.dev/go.opentelemetry.io/otel)
+[![Go Report Card](https://goreportcard.com/badge/go.opentelemetry.io/otel)](https://goreportcard.com/report/go.opentelemetry.io/otel)
+[![Slack](https://img.shields.io/badge/slack-@cncf/otel--go-brightgreen.svg?logo=slack)](https://cloud-native.slack.com/archives/C01NPAXACKT)
+
+OpenTelemetry-Go is the [Go](https://golang.org/) implementation of [OpenTelemetry](https://opentelemetry.io/).
+It provides a set of APIs to directly measure performance and behavior of your software and send this data to observability platforms.
+
+## Project Status
+
+| Signal  | Status     | Project |
+| ------- | ---------- | ------- |
+| Traces  | Stable     | N/A     |
+| Metrics | Alpha      | N/A     |
+| Logs    | Frozen [1] | N/A     |
+
+- [1]: The Logs signal development is halted for this project while we develop both Traces and Metrics.
+   No Logs Pull Requests are currently being accepted.
+
+Progress and status specific to this repository is tracked in our local
+[project boards](https://github.com/open-telemetry/opentelemetry-go/projects)
+and
+[milestones](https://github.com/open-telemetry/opentelemetry-go/milestones).
+
+Project versioning information and stability guarantees can be found in the
+[versioning documentation](./VERSIONING.md).
+
+### Compatibility
+
+OpenTelemetry-Go attempts to track the current supported versions of the
+[Go language](https://golang.org/doc/devel/release#policy). The release
+schedule after a new minor version of go is as follows:
+
+- The first release or one month, which ever is sooner, will add build steps for the new go version.
+- The first release after three months will remove support for the oldest go version.
+
+This project is tested on the following systems.
+
+| OS      | Go Version | Architecture |
+| ------- | ---------- | ------------ |
+| Ubuntu  | 1.18       | amd64        |
+| Ubuntu  | 1.17       | amd64        |
+| Ubuntu  | 1.18       | 386          |
+| Ubuntu  | 1.17       | 386          |
+| MacOS   | 1.18       | amd64        |
+| MacOS   | 1.17       | amd64        |
+| Windows | 1.18       | amd64        |
+| Windows | 1.17       | amd64        |
+| Windows | 1.18       | 386          |
+| Windows | 1.17       | 386          |
+
+While this project should work for other systems, no compatibility guarantees
+are made for those systems currently.
+
+## Getting Started
+
+You can find a getting started guide on [opentelemetry.io](https://opentelemetry.io/docs/go/getting-started/).
+
+OpenTelemetry's goal is to provide a single set of APIs to capture distributed
+traces and metrics from your application and send them to an observability
+platform. This project allows you to do just that for applications written in
+Go. There are two steps to this process: instrument your application, and
+configure an exporter.
+
+### Instrumentation
+
+To start capturing distributed traces and metric events from your application
+it first needs to be instrumented. The easiest way to do this is by using an
+instrumentation library for your code. Be sure to check out [the officially
+supported instrumentation
+libraries](https://github.com/open-telemetry/opentelemetry-go-contrib/tree/main/instrumentation).
+
+If you need to extend the telemetry an instrumentation library provides or want
+to build your own instrumentation for your application directly you will need
+to use the
+[Go otel](https://pkg.go.dev/go.opentelemetry.io/otel)
+package. The included [examples](./example/) are a good way to see some
+practical uses of this process.
+
+### Export
+
+Now that your application is instrumented to collect telemetry, it needs an
+export pipeline to send that telemetry to an observability platform.
+
+All officially supported exporters for the OpenTelemetry project are contained in the [exporters directory](./exporters).
+
+| Exporter                              | Metrics | Traces |
+| :-----------------------------------: | :-----: | :----: |
+| [Jaeger](./exporters/jaeger/)         |         | ✓      |
+| [OTLP](./exporters/otlp/)             | ✓       | ✓      |
+| [Prometheus](./exporters/prometheus/) | ✓       |        |
+| [stdout](./exporters/stdout/)         | ✓       | ✓      |
+| [Zipkin](./exporters/zipkin/)         |         | ✓      |
+
+## Contributing
+
+See the [contributing documentation](CONTRIBUTING.md).

vendor/go.opentelemetry.io/otel/RELEASING.md

+# Release Process
+
+## Semantic Convention Generation
+
+New versions of the [OpenTelemetry specification] mean new versions of the `semconv` package need to be generated.
+The `semconv-generate` make target is used for this.
+
+1. Checkout a local copy of the [OpenTelemetry specification] to the desired release tag.
+2. Run the `make semconv-generate ...` target from this repository.
+
+For example,
+
+```sh
+export TAG="v1.7.0" # Change to the release version you are generating.
+export OTEL_SPEC_REPO="/absolute/path/to/opentelemetry-specification"
+git -C "$OTEL_SPEC_REPO" checkout "tags/$TAG"
+make semconv-generate # Uses the exported TAG and OTEL_SPEC_REPO.
+```
+
+This should create a new sub-package of [`semconv`](./semconv).
+Ensure things look correct before submitting a pull request to include the addition.
+
+## Pre-Release
+
+First, decide which module sets will be released and update their versions
+in `versions.yaml`.  Commit this change to a new branch.
+
+Update go.mod for submodules to depend on the new release which will happen in the next step.
+
+1. Run the `prerelease` make target. It creates a branch
+    `prerelease_<module set>_<new tag>` that will contain all release changes.
+
+    ```
+    make prerelease MODSET=<module set>
+    ```
+
+2. Verify the changes.
+
+    ```
+    git diff ...prerelease_<module set>_<new tag>
+    ```
+
+    This should have changed the version for all modules to be `<new tag>`.
+    If these changes look correct, merge them into your pre-release branch:
+
+    ```go
+    git merge prerelease_<module set>_<new tag>
+    ```
+
+3. Update the [Changelog](./CHANGELOG.md).
+   - Make sure all relevant changes for this release are included and are in language that non-contributors to the project can understand.
+       To verify this, you can look directly at the commits since the `<last tag>`.
+
+       ```
+       git --no-pager log --pretty=oneline "<last tag>..HEAD"
+       ```
+
+   - Move all the `Unreleased` changes into a new section following the title scheme (`[<new tag>] - <date of release>`).
+   - Update all the appropriate links at the bottom.
+
+4. Push the changes to upstream and create a Pull Request on GitHub.
+    Be sure to include the curated changes from the [Changelog](./CHANGELOG.md) in the description.
+
+## Tag
+
+Once the Pull Request with all the version changes has been approved and merged it is time to tag the merged commit.
+
+***IMPORTANT***: It is critical you use the same tag that you used in the Pre-Release step!
+Failure to do so will leave things in a broken state. As long as you do not
+change `versions.yaml` between pre-release and this step, things should be fine.
+
+***IMPORTANT***: [There is currently no way to remove an incorrectly tagged version of a Go module](https://github.com/golang/go/issues/34189).
+It is critical you make sure the version you push upstream is correct.
+[Failure to do so will lead to minor emergencies and tough to work around](https://github.com/open-telemetry/opentelemetry-go/issues/331).
+
+1. For each module set that will be released, run the `add-tags` make target
+    using the `<commit-hash>` of the commit on the main branch for the merged Pull Request.
+
+    ```
+    make add-tags MODSET=<module set> COMMIT=<commit hash>
+    ```
+
+    It should only be necessary to provide an explicit `COMMIT` value if the
+    current `HEAD` of your working directory is not the correct commit.
+
+2. Push tags to the upstream remote (not your fork: `github.com/open-telemetry/opentelemetry-go.git`).
+    Make sure you push all sub-modules as well.
+
+    ```
+    git push upstream <new tag>
+    git push upstream <submodules-path/new tag>
+    ...
+    ```
+
+## Release
+
+Finally create a Release for the new `<new tag>` on GitHub.
+The release body should include all the release notes from the Changelog for this release.
+
+## Verify Examples
+
+After releasing verify that examples build outside of the repository.
+
+```
+./verify_examples.sh
+```
+
+The script copies examples into a different directory removes any `replace` declarations in `go.mod` and builds them.
+This ensures they build with the published release, not the local copy.
+
+## Post-Release
+
+### Contrib Repository
+
+Once verified be sure to [make a release for the `contrib` repository](https://github.com/open-telemetry/opentelemetry-go-contrib/blob/main/RELEASING.md) that uses this release.
+
+### Website Documentation
+
+Update [the documentation](./website_docs) for [the OpenTelemetry website](https://opentelemetry.io/docs/go/).
+Importantly, bump any package versions referenced to be the latest one you just released and ensure all code examples still compile and are accurate.
+
+[OpenTelemetry specification]: https://github.com/open-telemetry/opentelemetry-specification

vendor/go.opentelemetry.io/otel/VERSIONING.md

+# Versioning
+
+This document describes the versioning policy for this repository. This policy
+is designed so the following goals can be achieved.
+
+**Users are provided a codebase of value that is stable and secure.**
+
+## Policy
+
+* Versioning of this project will be idiomatic of a Go project using [Go
+  modules](https://github.com/golang/go/wiki/Modules).
+  * [Semantic import
+    versioning](https://github.com/golang/go/wiki/Modules#semantic-import-versioning)
+    will be used.
+    * Versions will comply with [semver
+      2.0](https://semver.org/spec/v2.0.0.html) with the following exceptions.
+      * New methods may be added to exported API interfaces. All exported
+        interfaces that fall within this exception will include the following
+        paragraph in their public documentation.
+
+        > Warning: methods may be added to this interface in minor releases.
+
+    * If a module is version `v2` or higher, the major version of the module
+      must be included as a `/vN` at the end of the module paths used in
+      `go.mod` files (e.g., `module go.opentelemetry.io/otel/v2`, `require
+      go.opentelemetry.io/otel/v2 v2.0.1`) and in the package import path
+      (e.g., `import "go.opentelemetry.io/otel/v2/trace"`). This includes the
+      paths used in `go get` commands (e.g., `go get
+      go.opentelemetry.io/otel/v2@v2.0.1`.  Note there is both a `/v2` and a
+      `@v2.0.1` in that example. One way to think about it is that the module
+      name now includes the `/v2`, so include `/v2` whenever you are using the
+      module name).
+    * If a module is version `v0` or `v1`, do not include the major version in
+      either the module path or the import path.
+  * Modules will be used to encapsulate signals and components.
+    * Experimental modules still under active development will be versioned at
+      `v0` to imply the stability guarantee defined by
+      [semver](https://semver.org/spec/v2.0.0.html#spec-item-4).
+
+      > Major version zero (0.y.z) is for initial development. Anything MAY
+      > change at any time. The public API SHOULD NOT be considered stable.
+
+    * Mature modules for which we guarantee a stable public API will be versioned
+      with a major version greater than `v0`.
+      * The decision to make a module stable will be made on a case-by-case
+        basis by the maintainers of this project.
+    * Experimental modules will start their versioning at `v0.0.0` and will
+      increment their minor version when backwards incompatible changes are
+      released and increment their patch version when backwards compatible
+      changes are released.
+    * All stable modules that use the same major version number will use the
+      same entire version number.
+      * Stable modules may be released with an incremented minor or patch
+        version even though that module has not been changed, but rather so
+        that it will remain at the same version as other stable modules that
+        did undergo change.
+      * When an experimental module becomes stable a new stable module version
+        will be released and will include this now stable module. The new
+        stable module version will be an increment of the minor version number
+        and will be applied to all existing stable modules as well as the newly
+        stable module being released.
+* Versioning of the associated [contrib
+  repository](https://github.com/open-telemetry/opentelemetry-go-contrib) of
+  this project will be idiomatic of a Go project using [Go
+  modules](https://github.com/golang/go/wiki/Modules).
+  * [Semantic import
+    versioning](https://github.com/golang/go/wiki/Modules#semantic-import-versioning)
+    will be used.
+    * Versions will comply with [semver 2.0](https://semver.org/spec/v2.0.0.html).
+    * If a module is version `v2` or higher, the
+      major version of the module must be included as a `/vN` at the end of the
+      module paths used in `go.mod` files (e.g., `module
+      go.opentelemetry.io/contrib/instrumentation/host/v2`, `require
+      go.opentelemetry.io/contrib/instrumentation/host/v2 v2.0.1`) and in the
+      package import path (e.g., `import
+      "go.opentelemetry.io/contrib/instrumentation/host/v2"`). This includes
+      the paths used in `go get` commands (e.g., `go get
+      go.opentelemetry.io/contrib/instrumentation/host/v2@v2.0.1`.  Note there
+      is both a `/v2` and a `@v2.0.1` in that example. One way to think about
+      it is that the module name now includes the `/v2`, so include `/v2`
+      whenever you are using the module name).
+    * If a module is version `v0` or `v1`, do not include the major version
+      in either the module path or the import path.
+  * In addition to public APIs, telemetry produced by stable instrumentation
+    will remain stable and backwards compatible. This is to avoid breaking
+    alerts and dashboard.
+  * Modules will be used to encapsulate instrumentation, detectors, exporters,
+    propagators, and any other independent sets of related components.
+    * Experimental modules still under active development will be versioned at
+      `v0` to imply the stability guarantee defined by
+      [semver](https://semver.org/spec/v2.0.0.html#spec-item-4).
+
+      > Major version zero (0.y.z) is for initial development. Anything MAY
+      > change at any time. The public API SHOULD NOT be considered stable.
+
+    * Mature modules for which we guarantee a stable public API and telemetry will
+      be versioned with a major version greater than `v0`.
+    * Experimental modules will start their versioning at `v0.0.0` and will
+      increment their minor version when backwards incompatible changes are
+      released and increment their patch version when backwards compatible
+      changes are released.
+    * Stable contrib modules cannot depend on experimental modules from this
+      project.
+    * All stable contrib modules of the same major version with this project
+      will use the same entire version as this project.
+      * Stable modules may be released with an incremented minor or patch
+        version even though that module's code has not been changed. Instead
+        the only change that will have been included is to have updated that
+        modules dependency on this project's stable APIs.
+      * When an experimental module in contrib becomes stable a new stable
+        module version will be released and will include this now stable
+        module. The new stable module version will be an increment of the minor
+        version number and will be applied to all existing stable contrib
+        modules, this project's modules, and the newly stable module being
+        released.
+  * Contrib modules will be kept up to date with this project's releases.
+    * Due to the dependency contrib modules will implicitly have on this
+      project's modules the release of stable contrib modules to match the
+      released version number will be staggered after this project's release.
+      There is no explicit time guarantee for how long after this projects
+      release the contrib release will be. Effort should be made to keep them
+      as close in time as possible.
+    * No additional stable release in this project can be made until the
+      contrib repository has a matching stable release.
+    * No release can be made in the contrib repository after this project's
+      stable release except for a stable release of the contrib repository.
+* GitHub releases will be made for all releases.
+* Go modules will be made available at Go package mirrors.
+
+## Example Versioning Lifecycle
+
+To better understand the implementation of the above policy the following
+example is provided. This project is simplified to include only the following
+modules and their versions:
+
+* `otel`: `v0.14.0`
+* `otel/trace`: `v0.14.0`
+* `otel/metric`: `v0.14.0`
+* `otel/baggage`: `v0.14.0`
+* `otel/sdk/trace`: `v0.14.0`
+* `otel/sdk/metric`: `v0.14.0`
+
+These modules have been developed to a point where the `otel/trace`,
+`otel/baggage`, and `otel/sdk/trace` modules have reached a point that they
+should be considered for a stable release. The `otel/metric` and
+`otel/sdk/metric` are still under active development and the `otel` module
+depends on both `otel/trace` and `otel/metric`.
+
+The `otel` package is refactored to remove its dependencies on `otel/metric` so
+it can be released as stable as well. With that done the following release
+candidates are made:
+
+* `otel`: `v1.0.0-RC1`
+* `otel/trace`: `v1.0.0-RC1`
+* `otel/baggage`: `v1.0.0-RC1`
+* `otel/sdk/trace`: `v1.0.0-RC1`
+
+The `otel/metric` and `otel/sdk/metric` modules remain at `v0.14.0`.
+
+A few minor issues are discovered in the `otel/trace` package. These issues are
+resolved with some minor, but backwards incompatible, changes and are released
+as a second release candidate:
+
+* `otel`: `v1.0.0-RC2`
+* `otel/trace`: `v1.0.0-RC2`
+* `otel/baggage`: `v1.0.0-RC2`
+* `otel/sdk/trace`: `v1.0.0-RC2`
+
+Notice that all module version numbers are incremented to adhere to our
+versioning policy.
+
+After these release candidates have been evaluated to satisfaction, they are
+released as version `v1.0.0`.
+
+* `otel`: `v1.0.0`
+* `otel/trace`: `v1.0.0`
+* `otel/baggage`: `v1.0.0`
+* `otel/sdk/trace`: `v1.0.0`
+
+Since both the `go` utility and the Go module system support [the semantic
+versioning definition of
+precedence](https://semver.org/spec/v2.0.0.html#spec-item-11), this release
+will correctly be interpreted as the successor to the previous release
+candidates.
+
+Active development of this project continues. The `otel/metric` module now has
+backwards incompatible changes to its API that need to be released and the
+`otel/baggage` module has a minor bug fix that needs to be released. The
+following release is made:
+
+* `otel`: `v1.0.1`
+* `otel/trace`: `v1.0.1`
+* `otel/metric`: `v0.15.0`
+* `otel/baggage`: `v1.0.1`
+* `otel/sdk/trace`: `v1.0.1`
+* `otel/sdk/metric`: `v0.15.0`
+
+Notice that, again, all stable module versions are incremented in unison and
+the `otel/sdk/metric` package, which depends on the `otel/metric` package, also
+bumped its version. This bump of the `otel/sdk/metric` package makes sense
+given their coupling, though it is not explicitly required by our versioning
+policy.
+
+As we progress, the `otel/metric` and `otel/sdk/metric` packages have reached a
+point where they should be evaluated for stability. The `otel` module is
+reintegrated with the `otel/metric` package and the following release is made:
+
+* `otel`: `v1.1.0-RC1`
+* `otel/trace`: `v1.1.0-RC1`
+* `otel/metric`: `v1.1.0-RC1`
+* `otel/baggage`: `v1.1.0-RC1`
+* `otel/sdk/trace`: `v1.1.0-RC1`
+* `otel/sdk/metric`: `v1.1.0-RC1`
+
+All the modules are evaluated and determined to a viable stable release. They
+are then released as version `v1.1.0` (the minor version is incremented to
+indicate the addition of new signal).
+
+* `otel`: `v1.1.0`
+* `otel/trace`: `v1.1.0`
+* `otel/metric`: `v1.1.0`
+* `otel/baggage`: `v1.1.0`
+* `otel/sdk/trace`: `v1.1.0`
+* `otel/sdk/metric`: `v1.1.0`

vendor/go.opencensus.io/tag/profile_not19.go → vendor/go.opentelemetry.io/otel/attribute/doc.go

-// Copyright 2018, OpenCensus Authors
+// Copyright The OpenTelemetry Authors
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -12,12 +12,5 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// +build !go1.9
-
-package tag
-
-import "context"
-
-func do(ctx context.Context, f func(ctx context.Context)) {
-	f(ctx)
-}
+// Package attribute provides key and value attributes.
+package attribute // import "go.opentelemetry.io/otel/attribute"

vendor/go.opentelemetry.io/otel/attribute/encoder.go

+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attribute // import "go.opentelemetry.io/otel/attribute"
+
+import (
+	"bytes"
+	"sync"
+	"sync/atomic"
+)
+
+type (
+	// Encoder is a mechanism for serializing an attribute set into a specific
+	// string representation that supports caching, to avoid repeated
+	// serialization. An example could be an exporter encoding the attribute
+	// set into a wire representation.
+	Encoder interface {
+		// Encode returns the serialized encoding of the attribute set using
+		// its Iterator. This result may be cached by a attribute.Set.
+		Encode(iterator Iterator) string
+
+		// ID returns a value that is unique for each class of attribute
+		// encoder. Attribute encoders allocate these using `NewEncoderID`.
+		ID() EncoderID
+	}
+
+	// EncoderID is used to identify distinct Encoder
+	// implementations, for caching encoded results.
+	EncoderID struct {
+		value uint64
+	}
+
+	// defaultAttrEncoder uses a sync.Pool of buffers to reduce the number of
+	// allocations used in encoding attributes. This implementation encodes a
+	// comma-separated list of key=value, with '/'-escaping of '=', ',', and
+	// '\'.
+	defaultAttrEncoder struct {
+		// pool is a pool of attribute set builders. The buffers in this pool
+		// grow to a size that most attribute encodings will not allocate new
+		// memory.
+		pool sync.Pool // *bytes.Buffer
+	}
+)
+
+// escapeChar is used to ensure uniqueness of the attribute encoding where
+// keys or values contain either '=' or ','.  Since there is no parser needed
+// for this encoding and its only requirement is to be unique, this choice is
+// arbitrary.  Users will see these in some exporters (e.g., stdout), so the
+// backslash ('\') is used as a conventional choice.
+const escapeChar = '\\'
+
+var (
+	_ Encoder = &defaultAttrEncoder{}
+
+	// encoderIDCounter is for generating IDs for other attribute encoders.
+	encoderIDCounter uint64
+
+	defaultEncoderOnce     sync.Once
+	defaultEncoderID       = NewEncoderID()
+	defaultEncoderInstance *defaultAttrEncoder
+)
+
+// NewEncoderID returns a unique attribute encoder ID. It should be called
+// once per each type of attribute encoder. Preferably in init() or in var
+// definition.
+func NewEncoderID() EncoderID {
+	return EncoderID{value: atomic.AddUint64(&encoderIDCounter, 1)}
+}
+
+// DefaultEncoder returns an attribute encoder that encodes attributes in such
+// a way that each escaped attribute's key is followed by an equal sign and
+// then by an escaped attribute's value. All key-value pairs are separated by
+// a comma.
+//
+// Escaping is done by prepending a backslash before either a backslash, equal
+// sign or a comma.
+func DefaultEncoder() Encoder {
+	defaultEncoderOnce.Do(func() {
+		defaultEncoderInstance = &defaultAttrEncoder{
+			pool: sync.Pool{
+				New: func() interface{} {
+					return &bytes.Buffer{}
+				},
+			},
+		}
+	})
+	return defaultEncoderInstance
+}
+
+// Encode is a part of an implementation of the AttributeEncoder interface.
+func (d *defaultAttrEncoder) Encode(iter Iterator) string {
+	buf := d.pool.Get().(*bytes.Buffer)
+	defer d.pool.Put(buf)
+	buf.Reset()
+
+	for iter.Next() {
+		i, keyValue := iter.IndexedAttribute()
+		if i > 0 {
+			_, _ = buf.WriteRune(',')
+		}
+		copyAndEscape(buf, string(keyValue.Key))
+
+		_, _ = buf.WriteRune('=')
+
+		if keyValue.Value.Type() == STRING {
+			copyAndEscape(buf, keyValue.Value.AsString())
+		} else {
+			_, _ = buf.WriteString(keyValue.Value.Emit())
+		}
+	}
+	return buf.String()
+}
+
+// ID is a part of an implementation of the AttributeEncoder interface.
+func (*defaultAttrEncoder) ID() EncoderID {
+	return defaultEncoderID
+}
+
+// copyAndEscape escapes `=`, `,` and its own escape character (`\`),
+// making the default encoding unique.
+func copyAndEscape(buf *bytes.Buffer, val string) {
+	for _, ch := range val {
+		switch ch {
+		case '=', ',', escapeChar:
+			_, _ = buf.WriteRune(escapeChar)
+		}
+		_, _ = buf.WriteRune(ch)
+	}
+}
+
+// Valid returns true if this encoder ID was allocated by
+// `NewEncoderID`.  Invalid encoder IDs will not be cached.
+func (id EncoderID) Valid() bool {
+	return id.value != 0
+}

vendor/go.opentelemetry.io/otel/attribute/iterator.go

+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attribute // import "go.opentelemetry.io/otel/attribute"
+
+// Iterator allows iterating over the set of attributes in order, sorted by
+// key.
+type Iterator struct {
+	storage *Set
+	idx     int
+}
+
+// MergeIterator supports iterating over two sets of attributes while
+// eliminating duplicate values from the combined set. The first iterator
+// value takes precedence.
+type MergeIterator struct {
+	one     oneIterator
+	two     oneIterator
+	current KeyValue
+}
+
+type oneIterator struct {
+	iter Iterator
+	done bool
+	attr KeyValue
+}
+
+// Next moves the iterator to the next position. Returns false if there are no
+// more attributes.
+func (i *Iterator) Next() bool {
+	i.idx++
+	return i.idx < i.Len()
+}
+
+// Label returns current KeyValue. Must be called only after Next returns
+// true.
+//
+// Deprecated: Use Attribute instead.
+func (i *Iterator) Label() KeyValue {
+	return i.Attribute()
+}
+
+// Attribute returns the current KeyValue of the Iterator. It must be called
+// only after Next returns true.
+func (i *Iterator) Attribute() KeyValue {
+	kv, _ := i.storage.Get(i.idx)
+	return kv
+}
+
+// IndexedLabel returns current index and attribute. Must be called only
+// after Next returns true.
+//
+// Deprecated: Use IndexedAttribute instead.
+func (i *Iterator) IndexedLabel() (int, KeyValue) {
+	return i.idx, i.Attribute()
+}
+
+// IndexedAttribute returns current index and attribute. Must be called only
+// after Next returns true.
+func (i *Iterator) IndexedAttribute() (int, KeyValue) {
+	return i.idx, i.Attribute()
+}
+
+// Len returns a number of attributes in the iterated set.
+func (i *Iterator) Len() int {
+	return i.storage.Len()
+}
+
+// ToSlice is a convenience function that creates a slice of attributes from
+// the passed iterator. The iterator is set up to start from the beginning
+// before creating the slice.
+func (i *Iterator) ToSlice() []KeyValue {
+	l := i.Len()
+	if l == 0 {
+		return nil
+	}
+	i.idx = -1
+	slice := make([]KeyValue, 0, l)
+	for i.Next() {
+		slice = append(slice, i.Attribute())
+	}
+	return slice
+}
+
+// NewMergeIterator returns a MergeIterator for merging two attribute sets.
+// Duplicates are resolved by taking the value from the first set.
+func NewMergeIterator(s1, s2 *Set) MergeIterator {
+	mi := MergeIterator{
+		one: makeOne(s1.Iter()),
+		two: makeOne(s2.Iter()),
+	}
+	return mi
+}
+
+func makeOne(iter Iterator) oneIterator {
+	oi := oneIterator{
+		iter: iter,
+	}
+	oi.advance()
+	return oi
+}
+
+func (oi *oneIterator) advance() {
+	if oi.done = !oi.iter.Next(); !oi.done {
+		oi.attr = oi.iter.Attribute()
+	}
+}
+
+// Next returns true if there is another attribute available.
+func (m *MergeIterator) Next() bool {
+	if m.one.done && m.two.done {
+		return false
+	}
+	if m.one.done {
+		m.current = m.two.attr
+		m.two.advance()
+		return true
+	}
+	if m.two.done {
+		m.current = m.one.attr
+		m.one.advance()
+		return true
+	}
+	if m.one.attr.Key == m.two.attr.Key {
+		m.current = m.one.attr // first iterator attribute value wins
+		m.one.advance()
+		m.two.advance()
+		return true
+	}
+	if m.one.attr.Key < m.two.attr.Key {
+		m.current = m.one.attr
+		m.one.advance()
+		return true
+	}
+	m.current = m.two.attr
+	m.two.advance()
+	return true
+}
+
+// Label returns the current value after Next() returns true.
+//
+// Deprecated: Use Attribute instead.
+func (m *MergeIterator) Label() KeyValue {
+	return m.current
+}
+
+// Attribute returns the current value after Next() returns true.
+func (m *MergeIterator) Attribute() KeyValue {
+	return m.current
+}

vendor/go.opentelemetry.io/otel/attribute/key.go

+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attribute // import "go.opentelemetry.io/otel/attribute"
+
+// Key represents the key part in key-value pairs. It's a string. The
+// allowed character set in the key depends on the use of the key.
+type Key string
+
+// Bool creates a KeyValue instance with a BOOL Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- Bool(name, value).
+func (k Key) Bool(v bool) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: BoolValue(v),
+	}
+}
+
+// BoolSlice creates a KeyValue instance with a BOOLSLICE Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- BoolSlice(name, value).
+func (k Key) BoolSlice(v []bool) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: BoolSliceValue(v),
+	}
+}
+
+// Int creates a KeyValue instance with an INT64 Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- Int(name, value).
+func (k Key) Int(v int) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: IntValue(v),
+	}
+}
+
+// IntSlice creates a KeyValue instance with an INT64SLICE Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- IntSlice(name, value).
+func (k Key) IntSlice(v []int) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: IntSliceValue(v),
+	}
+}
+
+// Int64 creates a KeyValue instance with an INT64 Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- Int64(name, value).
+func (k Key) Int64(v int64) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: Int64Value(v),
+	}
+}
+
+// Int64Slice creates a KeyValue instance with an INT64SLICE Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- Int64Slice(name, value).
+func (k Key) Int64Slice(v []int64) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: Int64SliceValue(v),
+	}
+}
+
+// Float64 creates a KeyValue instance with a FLOAT64 Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- Float64(name, value).
+func (k Key) Float64(v float64) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: Float64Value(v),
+	}
+}
+
+// Float64Slice creates a KeyValue instance with a FLOAT64SLICE Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- Float64(name, value).
+func (k Key) Float64Slice(v []float64) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: Float64SliceValue(v),
+	}
+}
+
+// String creates a KeyValue instance with a STRING Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- String(name, value).
+func (k Key) String(v string) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: StringValue(v),
+	}
+}
+
+// StringSlice creates a KeyValue instance with a STRINGSLICE Value.
+//
+// If creating both a key and value at the same time, use the provided
+// convenience function instead -- StringSlice(name, value).
+func (k Key) StringSlice(v []string) KeyValue {
+	return KeyValue{
+		Key:   k,
+		Value: StringSliceValue(v),
+	}
+}
+
+// Defined returns true for non-empty keys.
+func (k Key) Defined() bool {
+	return len(k) != 0
+}

vendor/go.opentelemetry.io/otel/attribute/kv.go

+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attribute // import "go.opentelemetry.io/otel/attribute"
+
+import (
+	"fmt"
+)
+
+// KeyValue holds a key and value pair.
+type KeyValue struct {
+	Key   Key
+	Value Value
+}
+
+// Valid returns if kv is a valid OpenTelemetry attribute.
+func (kv KeyValue) Valid() bool {
+	return kv.Key.Defined() && kv.Value.Type() != INVALID
+}
+
+// Bool creates a KeyValue with a BOOL Value type.
+func Bool(k string, v bool) KeyValue {
+	return Key(k).Bool(v)
+}
+
+// BoolSlice creates a KeyValue with a BOOLSLICE Value type.
+func BoolSlice(k string, v []bool) KeyValue {
+	return Key(k).BoolSlice(v)
+}
+
+// Int creates a KeyValue with an INT64 Value type.
+func Int(k string, v int) KeyValue {
+	return Key(k).Int(v)
+}
+
+// IntSlice creates a KeyValue with an INT64SLICE Value type.
+func IntSlice(k string, v []int) KeyValue {
+	return Key(k).IntSlice(v)
+}
+
+// Int64 creates a KeyValue with an INT64 Value type.
+func Int64(k string, v int64) KeyValue {
+	return Key(k).Int64(v)
+}
+
+// Int64Slice creates a KeyValue with an INT64SLICE Value type.
+func Int64Slice(k string, v []int64) KeyValue {
+	return Key(k).Int64Slice(v)
+}
+
+// Float64 creates a KeyValue with a FLOAT64 Value type.
+func Float64(k string, v float64) KeyValue {
+	return Key(k).Float64(v)
+}
+
+// Float64Slice creates a KeyValue with a FLOAT64SLICE Value type.
+func Float64Slice(k string, v []float64) KeyValue {
+	return Key(k).Float64Slice(v)
+}
+
+// String creates a KeyValue with a STRING Value type.
+func String(k, v string) KeyValue {
+	return Key(k).String(v)
+}
+
+// StringSlice creates a KeyValue with a STRINGSLICE Value type.
+func StringSlice(k string, v []string) KeyValue {
+	return Key(k).StringSlice(v)
+}
+
+// Stringer creates a new key-value pair with a passed name and a string
+// value generated by the passed Stringer interface.
+func Stringer(k string, v fmt.Stringer) KeyValue {
+	return Key(k).String(v.String())
+}

vendor/go.opentelemetry.io/otel/attribute/set.go

+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attribute // import "go.opentelemetry.io/otel/attribute"
+
+import (
+	"encoding/json"
+	"reflect"
+	"sort"
+)
+
+type (
+	// Set is the representation for a distinct attribute set. It manages an
+	// immutable set of attributes, with an internal cache for storing
+	// attribute encodings.
+	//
+	// This type supports the Equivalent method of comparison using values of
+	// type Distinct.
+	Set struct {
+		equivalent Distinct
+	}
+
+	// Distinct wraps a variable-size array of KeyValue, constructed with keys
+	// in sorted order. This can be used as a map key or for equality checking
+	// between Sets.
+	Distinct struct {
+		iface interface{}
+	}
+
+	// Filter supports removing certain attributes from attribute sets. When
+	// the filter returns true, the attribute will be kept in the filtered
+	// attribute set. When the filter returns false, the attribute is excluded
+	// from the filtered attribute set, and the attribute instead appears in
+	// the removed list of excluded attributes.
+	Filter func(KeyValue) bool
+
+	// Sortable implements sort.Interface, used for sorting KeyValue. This is
+	// an exported type to support a memory optimization. A pointer to one of
+	// these is needed for the call to sort.Stable(), which the caller may
+	// provide in order to avoid an allocation. See NewSetWithSortable().
+	Sortable []KeyValue
+)
+
+var (
+	// keyValueType is used in computeDistinctReflect.
+	keyValueType = reflect.TypeOf(KeyValue{})
+
+	// emptySet is returned for empty attribute sets.
+	emptySet = &Set{
+		equivalent: Distinct{
+			iface: [0]KeyValue{},
+		},
+	}
+)
+
+// EmptySet returns a reference to a Set with no elements.
+//
+// This is a convenience provided for optimized calling utility.
+func EmptySet() *Set {
+	return emptySet
+}
+
+// reflectValue abbreviates reflect.ValueOf(d).
+func (d Distinct) reflectValue() reflect.Value {
+	return reflect.ValueOf(d.iface)
+}
+
+// Valid returns true if this value refers to a valid Set.
+func (d Distinct) Valid() bool {
+	return d.iface != nil
+}
+
+// Len returns the number of attributes in this set.
+func (l *Set) Len() int {
+	if l == nil || !l.equivalent.Valid() {
+		return 0
+	}
+	return l.equivalent.reflectValue().Len()
+}
+
+// Get returns the KeyValue at ordered position idx in this set.
+func (l *Set) Get(idx int) (KeyValue, bool) {
+	if l == nil {
+		return KeyValue{}, false
+	}
+	value := l.equivalent.reflectValue()
+
+	if idx >= 0 && idx < value.Len() {
+		// Note: The Go compiler successfully avoids an allocation for
+		// the interface{} conversion here:
+		return value.Index(idx).Interface().(KeyValue), true
+	}
+
+	return KeyValue{}, false
+}
+
+// Value returns the value of a specified key in this set.
+func (l *Set) Value(k Key) (Value, bool) {
+	if l == nil {
+		return Value{}, false
+	}
+	rValue := l.equivalent.reflectValue()
+	vlen := rValue.Len()
+
+	idx := sort.Search(vlen, func(idx int) bool {
+		return rValue.Index(idx).Interface().(KeyValue).Key >= k
+	})
+	if idx >= vlen {
+		return Value{}, false
+	}
+	keyValue := rValue.Index(idx).Interface().(KeyValue)
+	if k == keyValue.Key {
+		return keyValue.Value, true
+	}
+	return Value{}, false
+}
+
+// HasValue tests whether a key is defined in this set.
+func (l *Set) HasValue(k Key) bool {
+	if l == nil {
+		return false
+	}
+	_, ok := l.Value(k)
+	return ok
+}
+
+// Iter returns an iterator for visiting the attributes in this set.
+func (l *Set) Iter() Iterator {
+	return Iterator{
+		storage: l,
+		idx:     -1,
+	}
+}
+
+// ToSlice returns the set of attributes belonging to this set, sorted, where
+// keys appear no more than once.
+func (l *Set) ToSlice() []KeyValue {
+	iter := l.Iter()
+	return iter.ToSlice()
+}
+
+// Equivalent returns a value that may be used as a map key. The Distinct type
+// guarantees that the result will equal the equivalent. Distinct value of any
+// attribute set with the same elements as this, where sets are made unique by
+// choosing the last value in the input for any given key.
+func (l *Set) Equivalent() Distinct {
+	if l == nil || !l.equivalent.Valid() {
+		return emptySet.equivalent
+	}
+	return l.equivalent
+}
+
+// Equals returns true if the argument set is equivalent to this set.
+func (l *Set) Equals(o *Set) bool {
+	return l.Equivalent() == o.Equivalent()
+}
+
+// Encoded returns the encoded form of this set, according to encoder.
+func (l *Set) Encoded(encoder Encoder) string {
+	if l == nil || encoder == nil {
+		return ""
+	}
+
+	return encoder.Encode(l.Iter())
+}
+
+func empty() Set {
+	return Set{
+		equivalent: emptySet.equivalent,
+	}
+}
+
+// NewSet returns a new Set. See the documentation for
+// NewSetWithSortableFiltered for more details.
+//
+// Except for empty sets, this method adds an additional allocation compared
+// with calls that include a Sortable.
+func NewSet(kvs ...KeyValue) Set {
+	// Check for empty set.
+	if len(kvs) == 0 {
+		return empty()
+	}
+	s, _ := NewSetWithSortableFiltered(kvs, new(Sortable), nil)
+	return s
+}
+
+// NewSetWithSortable returns a new Set. See the documentation for
+// NewSetWithSortableFiltered for more details.
+//
+// This call includes a Sortable option as a memory optimization.
+func NewSetWithSortable(kvs []KeyValue, tmp *Sortable) Set {
+	// Check for empty set.
+	if len(kvs) == 0 {
+		return empty()
+	}
+	s, _ := NewSetWithSortableFiltered(kvs, tmp, nil)
+	return s
+}
+
+// NewSetWithFiltered returns a new Set. See the documentation for
+// NewSetWithSortableFiltered for more details.
+//
+// This call includes a Filter to include/exclude attribute keys from the
+// return value. Excluded keys are returned as a slice of attribute values.
+func NewSetWithFiltered(kvs []KeyValue, filter Filter) (Set, []KeyValue) {
+	// Check for empty set.
+	if len(kvs) == 0 {
+		return empty(), nil
+	}
+	return NewSetWithSortableFiltered(kvs, new(Sortable), filter)
+}
+
+// NewSetWithSortableFiltered returns a new Set.
+//
+// Duplicate keys are eliminated by taking the last value.  This
+// re-orders the input slice so that unique last-values are contiguous
+// at the end of the slice.
+//
+// This ensures the following:
+//
+// - Last-value-wins semantics
+// - Caller sees the reordering, but doesn't lose values
+// - Repeated call preserve last-value wins.
+//
+// Note that methods are defined on Set, although this returns Set. Callers
+// can avoid memory allocations by:
+//
+// - allocating a Sortable for use as a temporary in this method
+// - allocating a Set for storing the return value of this constructor.
+//
+// The result maintains a cache of encoded attributes, by attribute.EncoderID.
+// This value should not be copied after its first use.
+//
+// The second []KeyValue return value is a list of attributes that were
+// excluded by the Filter (if non-nil).
+func NewSetWithSortableFiltered(kvs []KeyValue, tmp *Sortable, filter Filter) (Set, []KeyValue) {
+	// Check for empty set.
+	if len(kvs) == 0 {
+		return empty(), nil
+	}
+
+	*tmp = kvs
+
+	// Stable sort so the following de-duplication can implement
+	// last-value-wins semantics.
+	sort.Stable(tmp)
+
+	*tmp = nil
+
+	position := len(kvs) - 1
+	offset := position - 1
+
+	// The requirements stated above require that the stable
+	// result be placed in the end of the input slice, while
+	// overwritten values are swapped to the beginning.
+	//
+	// De-duplicate with last-value-wins semantics.  Preserve
+	// duplicate values at the beginning of the input slice.
+	for ; offset >= 0; offset-- {
+		if kvs[offset].Key == kvs[position].Key {
+			continue
+		}
+		position--
+		kvs[offset], kvs[position] = kvs[position], kvs[offset]
+	}
+	if filter != nil {
+		return filterSet(kvs[position:], filter)
+	}
+	return Set{
+		equivalent: computeDistinct(kvs[position:]),
+	}, nil
+}
+
+// filterSet reorders kvs so that included keys are contiguous at the end of
+// the slice, while excluded keys precede the included keys.
+func filterSet(kvs []KeyValue, filter Filter) (Set, []KeyValue) {
+	var excluded []KeyValue
+
+	// Move attributes that do not match the filter so they're adjacent before
+	// calling computeDistinct().
+	distinctPosition := len(kvs)
+
+	// Swap indistinct keys forward and distinct keys toward the
+	// end of the slice.
+	offset := len(kvs) - 1
+	for ; offset >= 0; offset-- {
+		if filter(kvs[offset]) {
+			distinctPosition--
+			kvs[offset], kvs[distinctPosition] = kvs[distinctPosition], kvs[offset]
+			continue
+		}
+	}
+	excluded = kvs[:distinctPosition]
+
+	return Set{
+		equivalent: computeDistinct(kvs[distinctPosition:]),
+	}, excluded
+}
+
+// Filter returns a filtered copy of this Set. See the documentation for
+// NewSetWithSortableFiltered for more details.
+func (l *Set) Filter(re Filter) (Set, []KeyValue) {
+	if re == nil {
+		return Set{
+			equivalent: l.equivalent,
+		}, nil
+	}
+
+	// Note: This could be refactored to avoid the temporary slice
+	// allocation, if it proves to be expensive.
+	return filterSet(l.ToSlice(), re)
+}
+
+// computeDistinct returns a Distinct using either the fixed- or
+// reflect-oriented code path, depending on the size of the input. The input
+// slice is assumed to already be sorted and de-duplicated.
+func computeDistinct(kvs []KeyValue) Distinct {
+	iface := computeDistinctFixed(kvs)
+	if iface == nil {
+		iface = computeDistinctReflect(kvs)
+	}
+	return Distinct{
+		iface: iface,
+	}
+}
+
+// computeDistinctFixed computes a Distinct for small slices. It returns nil
+// if the input is too large for this code path.
+func computeDistinctFixed(kvs []KeyValue) interface{} {
+	switch len(kvs) {
+	case 1:
+		ptr := new([1]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 2:
+		ptr := new([2]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 3:
+		ptr := new([3]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 4:
+		ptr := new([4]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 5:
+		ptr := new([5]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 6:
+		ptr := new([6]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 7:
+		ptr := new([7]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 8:
+		ptr := new([8]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 9:
+		ptr := new([9]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	case 10:
+		ptr := new([10]KeyValue)
+		copy((*ptr)[:], kvs)
+		return *ptr
+	default:
+		return nil
+	}
+}
+
+// computeDistinctReflect computes a Distinct using reflection, works for any
+// size input.
+func computeDistinctReflect(kvs []KeyValue) interface{} {
+	at := reflect.New(reflect.ArrayOf(len(kvs), keyValueType)).Elem()
+	for i, keyValue := range kvs {
+		*(at.Index(i).Addr().Interface().(*KeyValue)) = keyValue
+	}
+	return at.Interface()
+}
+
+// MarshalJSON returns the JSON encoding of the Set.
+func (l *Set) MarshalJSON() ([]byte, error) {
+	return json.Marshal(l.equivalent.iface)
+}
+
+// MarshalLog is the marshaling function used by the logging system to represent this exporter.
+func (l Set) MarshalLog() interface{} {
+	kvs := make(map[string]string)
+	for _, kv := range l.ToSlice() {
+		kvs[string(kv.Key)] = kv.Value.Emit()
+	}
+	return kvs
+}
+
+// Len implements sort.Interface.
+func (l *Sortable) Len() int {
+	return len(*l)
+}
+
+// Swap implements sort.Interface.
+func (l *Sortable) Swap(i, j int) {
+	(*l)[i], (*l)[j] = (*l)[j], (*l)[i]
+}
+
+// Less implements sort.Interface.
+func (l *Sortable) Less(i, j int) bool {
+	return (*l)[i].Key < (*l)[j].Key
+}

vendor/go.opentelemetry.io/otel/attribute/type_string.go

+// Code generated by "stringer -type=Type"; DO NOT EDIT.
+
+package attribute
+
+import "strconv"
+
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[INVALID-0]
+	_ = x[BOOL-1]
+	_ = x[INT64-2]
+	_ = x[FLOAT64-3]
+	_ = x[STRING-4]
+	_ = x[BOOLSLICE-5]
+	_ = x[INT64SLICE-6]
+	_ = x[FLOAT64SLICE-7]
+	_ = x[STRINGSLICE-8]
+}
+
+const _Type_name = "INVALIDBOOLINT64FLOAT64STRINGBOOLSLICEINT64SLICEFLOAT64SLICESTRINGSLICE"
+
+var _Type_index = [...]uint8{0, 7, 11, 16, 23, 29, 38, 48, 60, 71}
+
+func (i Type) String() string {
+	if i < 0 || i >= Type(len(_Type_index)-1) {
+		return "Type(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+	return _Type_name[_Type_index[i]:_Type_index[i+1]]
+}

vendor/go.opentelemetry.io/otel/attribute/value.go

+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attribute // import "go.opentelemetry.io/otel/attribute"
+
+import (
+	"encoding/json"
+	"fmt"
+	"strconv"
+
+	"go.opentelemetry.io/otel/internal"
+)
+
+//go:generate stringer -type=Type
+
+// Type describes the type of the data Value holds.
+type Type int // nolint: revive  // redefines builtin Type.
+
+// Value represents the value part in key-value pairs.
+type Value struct {
+	vtype    Type
+	numeric  uint64
+	stringly string
+	slice    interface{}
+}
+
+const (
+	// INVALID is used for a Value with no value set.
+	INVALID Type = iota
+	// BOOL is a boolean Type Value.
+	BOOL
+	// INT64 is a 64-bit signed integral Type Value.
+	INT64
+	// FLOAT64 is a 64-bit floating point Type Value.
+	FLOAT64
+	// STRING is a string Type Value.
+	STRING
+	// BOOLSLICE is a slice of booleans Type Value.
+	BOOLSLICE
+	// INT64SLICE is a slice of 64-bit signed integral numbers Type Value.
+	INT64SLICE
+	// FLOAT64SLICE is a slice of 64-bit floating point numbers Type Value.
+	FLOAT64SLICE
+	// STRINGSLICE is a slice of strings Type Value.
+	STRINGSLICE
+)
+
+// BoolValue creates a BOOL Value.
+func BoolValue(v bool) Value {
+	return Value{
+		vtype:   BOOL,
+		numeric: internal.BoolToRaw(v),
+	}
+}
+
+// BoolSliceValue creates a BOOLSLICE Value.
+func BoolSliceValue(v []bool) Value {
+	cp := make([]bool, len(v))
+	copy(cp, v)
+	return Value{
+		vtype: BOOLSLICE,
+		slice: &cp,
+	}
+}
+
+// IntValue creates an INT64 Value.
+func IntValue(v int) Value {
+	return Int64Value(int64(v))
+}
+
+// IntSliceValue creates an INTSLICE Value.
+func IntSliceValue(v []int) Value {
+	cp := make([]int64, 0, len(v))
+	for _, i := range v {
+		cp = append(cp, int64(i))
+	}
+	return Value{
+		vtype: INT64SLICE,
+		slice: &cp,
+	}
+}
+
+// Int64Value creates an INT64 Value.
+func Int64Value(v int64) Value {
+	return Value{
+		vtype:   INT64,
+		numeric: internal.Int64ToRaw(v),
+	}
+}
+
+// Int64SliceValue creates an INT64SLICE Value.
+func Int64SliceValue(v []int64) Value {
+	cp := make([]int64, len(v))
+	copy(cp, v)
+	return Value{
+		vtype: INT64SLICE,
+		slice: &cp,
+	}
+}
+
+// Float64Value creates a FLOAT64 Value.
+func Float64Value(v float64) Value {
+	return Value{
+		vtype:   FLOAT64,
+		numeric: internal.Float64ToRaw(v),
+	}
+}
+
+// Float64SliceValue creates a FLOAT64SLICE Value.
+func Float64SliceValue(v []float64) Value {
+	cp := make([]float64, len(v))
+	copy(cp, v)
+	return Value{
+		vtype: FLOAT64SLICE,
+		slice: &cp,
+	}
+}
+
+// StringValue creates a STRING Value.
+func StringValue(v string) Value {
+	return Value{
+		vtype:    STRING,
+		stringly: v,
+	}
+}
+
+// StringSliceValue creates a STRINGSLICE Value.
+func StringSliceValue(v []string) Value {
+	cp := make([]string, len(v))
+	copy(cp, v)
+	return Value{
+		vtype: STRINGSLICE,
+		slice: &cp,
+	}
+}
+
+// Type returns a type of the Value.
+func (v Value) Type() Type {
+	return v.vtype
+}
+
+// AsBool returns the bool value. Make sure that the Value's type is
+// BOOL.
+func (v Value) AsBool() bool {
+	return internal.RawToBool(v.numeric)
+}
+
+// AsBoolSlice returns the []bool value. Make sure that the Value's type is
+// BOOLSLICE.
+func (v Value) AsBoolSlice() []bool {
+	if s, ok := v.slice.(*[]bool); ok {
+		return *s
+	}
+	return nil
+}
+
+// AsInt64 returns the int64 value. Make sure that the Value's type is
+// INT64.
+func (v Value) AsInt64() int64 {
+	return internal.RawToInt64(v.numeric)
+}
+
+// AsInt64Slice returns the []int64 value. Make sure that the Value's type is
+// INT64SLICE.
+func (v Value) AsInt64Slice() []int64 {
+	if s, ok := v.slice.(*[]int64); ok {
+		return *s
+	}
+	return nil
+}
+
+// AsFloat64 returns the float64 value. Make sure that the Value's
+// type is FLOAT64.
+func (v Value) AsFloat64() float64 {
+	return internal.RawToFloat64(v.numeric)
+}
+
+// AsFloat64Slice returns the []float64 value. Make sure that the Value's type is
+// FLOAT64SLICE.
+func (v Value) AsFloat64Slice() []float64 {
+	if s, ok := v.slice.(*[]float64); ok {
+		return *s
+	}
+	return nil
+}
+
+// AsString returns the string value. Make sure that the Value's type
+// is STRING.
+func (v Value) AsString() string {
+	return v.stringly
+}
+
+// AsStringSlice returns the []string value. Make sure that the Value's type is
+// STRINGSLICE.
+func (v Value) AsStringSlice() []string {
+	if s, ok := v.slice.(*[]string); ok {
+		return *s
+	}
+	return nil
+}
+
+type unknownValueType struct{}
+
+// AsInterface returns Value's data as interface{}.
+func (v Value) AsInterface() interface{} {
+	switch v.Type() {
+	case BOOL:
+		return v.AsBool()
+	case BOOLSLICE:
+		return v.AsBoolSlice()
+	case INT64:
+		return v.AsInt64()
+	case INT64SLICE:
+		return v.AsInt64Slice()
+	case FLOAT64:
+		return v.AsFloat64()
+	case FLOAT64SLICE:
+		return v.AsFloat64Slice()
+	case STRING:
+		return v.stringly
+	case STRINGSLICE:
+		return v.AsStringSlice()
+	}
+	return unknownValueType{}
+}
+
+// Emit returns a string representation of Value's data.
+func (v Value) Emit() string {
+	switch v.Type() {
+	case BOOLSLICE:
+		return fmt.Sprint(*(v.slice.(*[]bool)))
+	case BOOL:
+		return strconv.FormatBool(v.AsBool())
+	case INT64SLICE:
+		return fmt.Sprint(*(v.slice.(*[]int64)))
+	case INT64:
+		return strconv.FormatInt(v.AsInt64(), 10)
+	case FLOAT64SLICE:
+		return fmt.Sprint(*(v.slice.(*[]float64)))
+	case FLOAT64:
+		return fmt.Sprint(v.AsFloat64())
+	case STRINGSLICE:
+		return fmt.Sprint(*(v.slice.(*[]string)))
+	case STRING:
+		return v.stringly
+	default:
+		return "unknown"
+	}
+}
+
+// MarshalJSON returns the JSON encoding of the Value.
+func (v Value) MarshalJSON() ([]byte, error) {
+	var jsonVal struct {
+		Type  string
+		Value interface{}
+	}
+	jsonVal.Type = v.Type().String()
+	jsonVal.Value = v.AsInterface()
+	return json.Marshal(jsonVal)
+}

vendor/go.opentelemetry.io/otel/baggage/baggage.go

+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package baggage // import "go.opentelemetry.io/otel/baggage"
+
+import (
+	"errors"
+	"fmt"
+	"net/url"
+	"regexp"
+	"strings"
+
+	"go.opentelemetry.io/otel/internal/baggage"
+)
+
+const (
+	maxMembers               = 180
+	maxBytesPerMembers       = 4096
+	maxBytesPerBaggageString = 8192
+
+	listDelimiter     = ","
+	keyValueDelimiter = "="
+	propertyDelimiter = ";"
+
+	keyDef      = `([\x21\x23-\x27\x2A\x2B\x2D\x2E\x30-\x39\x41-\x5a\x5e-\x7a\x7c\x7e]+)`
+	valueDef    = `([\x21\x23-\x2b\x2d-\x3a\x3c-\x5B\x5D-\x7e]*)`
+	keyValueDef = `\s*` + keyDef + `\s*` + keyValueDelimiter + `\s*` + valueDef + `\s*`
+)
+
+var (
+	keyRe      = regexp.MustCompile(`^` + keyDef + `$`)
+	valueRe    = regexp.MustCompile(`^` + valueDef + `$`)
+	propertyRe = regexp.MustCompile(`^(?:\s*` + keyDef + `\s*|` + keyValueDef + `)$`)
+)
+
+var (
+	errInvalidKey      = errors.New("invalid key")
+	errInvalidValue    = errors.New("invalid value")
+	errInvalidProperty = errors.New("invalid baggage list-member property")
+	errInvalidMember   = errors.New("invalid baggage list-member")
+	errMemberNumber    = errors.New("too many list-members in baggage-string")
+	errMemberBytes     = errors.New("list-member too large")
+	errBaggageBytes    = errors.New("baggage-string too large")
+)
+
+// Property is an additional metadata entry for a baggage list-member.
+type Property struct {
+	key, value string
+
+	// hasValue indicates if a zero-value value means the property does not
+	// have a value or if it was the zero-value.
+	hasValue bool
+
+	// hasData indicates whether the created property contains data or not.
+	// Properties that do not contain data are invalid with no other check
+	// required.
+	hasData bool
+}
+
+// NewKeyProperty returns a new Property for key.
+//
+// If key is invalid, an error will be returned.
+func NewKeyProperty(key string) (Property, error) {
+	if !keyRe.MatchString(key) {
+		return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidKey, key)
+	}
+
+	p := Property{key: key, hasData: true}
+	return p, nil
+}
+
+// NewKeyValueProperty returns a new Property for key with value.
+//
+// If key or value are invalid, an error will be returned.
+func NewKeyValueProperty(key, value string) (Property, error) {
+	if !keyRe.MatchString(key) {
+		return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidKey, key)
+	}
+	if !valueRe.MatchString(value) {
+		return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidValue, value)
+	}
+
+	p := Property{
+		key:      key,
+		value:    value,
+		hasValue: true,
+		hasData:  true,
+	}
+	return p, nil
+}
+
+func newInvalidProperty() Property {
+	return Property{}
+}
+
+// parseProperty attempts to decode a Property from the passed string. It
+// returns an error if the input is invalid according to the W3C Baggage
+// specification.
+func parseProperty(property string) (Property, error) {
+	if property == "" {
+		return newInvalidProperty(), nil
+	}
+
+	match := propertyRe.FindStringSubmatch(property)
+	if len(match) != 4 {
+		return newInvalidProperty(), fmt.Errorf("%w: %q", errInvalidProperty, property)
+	}
+
+	p := Property{hasData: true}
+	if match[1] != "" {
+		p.key = match[1]
+	} else {
+		p.key = match[2]
+		p.value = match[3]
+		p.hasValue = true
+	}
+
+	return p, nil
+}
+
+// validate ensures p conforms to the W3C Baggage specification, returning an
+// error otherwise.
+func (p Property) validate() error {
+	errFunc := func(err error) error {
+		return fmt.Errorf("invalid property: %w", err)
+	}
+
+	if !p.hasData {
+		return errFunc(fmt.Errorf("%w: %q", errInvalidProperty, p))
+	}
+
+	if !keyRe.MatchString(p.key) {
+		return errFunc(fmt.Errorf("%w: %q", errInvalidKey, p.key))
+	}
+	if p.hasValue && !valueRe.MatchString(p.value) {
+		return errFunc(fmt.Errorf("%w: %q", errInvalidValue, p.value))
+	}
+	if !p.hasValue && p.value != "" {
+		return errFunc(errors.New("inconsistent value"))
+	}
+	return nil
+}
+
+// Key returns the Property key.
+func (p Property) Key() string {
+	return p.key
+}
+
+// Value returns the Property value. Additionally, a boolean value is returned
+// indicating if the returned value is the empty if the Property has a value
+// that is empty or if the value is not set.
+func (p Property) Value() (string, bool) {
+	return p.value, p.hasValue
+}
+
+// String encodes Property into a string compliant with the W3C Baggage
+// specification.
+func (p Property) String() string {
+	if p.hasValue {
+		return fmt.Sprintf("%s%s%v", p.key, keyValueDelimiter, p.value)
+	}
+	return p.key
+}
+
+type properties []Property
+
+func fromInternalProperties(iProps []baggage.Property) properties {
+	if len(iProps) == 0 {
+		return nil
+	}
+
+	props := make(properties, len(iProps))
+	for i, p := range iProps {
+		props[i] = Property{
+			key:      p.Key,
+			value:    p.Value,
+			hasValue: p.HasValue,
+		}
+	}
+	return props
+}
+
+func (p properties) asInternal() []baggage.Property {
+	if len(p) == 0 {
+		return nil
+	}
+
+	iProps := make([]baggage.Property, len(p))
+	for i, prop := range p {
+		iProps[i] = baggage.Property{
+			Key:      prop.key,
+			Value:    prop.value,
+			HasValue: prop.hasValue,
+		}
+	}
+	return iProps
+}
+
+func (p properties) Copy() properties {
+	if len(p) == 0 {
+		return nil
+	}
+
+	props := make(properties, len(p))
+	copy(props, p)
+	return props
+}
+
+// validate ensures each Property in p conforms to the W3C Baggage
+// specification, returning an error otherwise.
+func (p properties) validate() error {
+	for _, prop := range p {
+		if err := prop.validate(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// String encodes properties into a string compliant with the W3C Baggage
+// specification.
+func (p properties) String() string {
+	props := make([]string, len(p))
+	for i, prop := range p {
+		props[i] = prop.String()
+	}
+	return strings.Join(props, propertyDelimiter)
+}
+
+// Member is a list-member of a baggage-string as defined by the W3C Baggage
+// specification.
+type Member struct {
+	key, value string
+	properties properties
+
+	// hasData indicates whether the created property contains data or not.
+	// Properties that do not contain data are invalid with no other check
+	// required.
+	hasData bool
+}
+
+// NewMember returns a new Member from the passed arguments. An error is
+// returned if the created Member would be invalid according to the W3C
+// Baggage specification.
+func NewMember(key, value string, props ...Property) (Member, error) {
+	m := Member{
+		key:        key,
+		value:      value,
+		properties: properties(props).Copy(),
+		hasData:    true,
+	}
+	if err := m.validate(); err != nil {
+		return newInvalidMember(), err
+	}
+
+	return m, nil
+}
+
+func newInvalidMember() Member {
+	return Member{}
+}
+
+// parseMember attempts to decode a Member from the passed string. It returns
+// an error if the input is invalid according to the W3C Baggage
+// specification.
+func parseMember(member string) (Member, error) {
+	if n := len(member); n > maxBytesPerMembers {
+		return newInvalidMember(), fmt.Errorf("%w: %d", errMemberBytes, n)
+	}
+
+	var (
+		key, value string
+		props      properties
+	)
+
+	parts := strings.SplitN(member, propertyDelimiter, 2)
+	switch len(parts) {
+	case 2:
+		// Parse the member properties.
+		for _, pStr := range strings.Split(parts[1], propertyDelimiter) {
+			p, err := parseProperty(pStr)
+			if err != nil {
+				return newInvalidMember(), err
+			}
+			props = append(props, p)
+		}
+		fallthrough
+	case 1:
+		// Parse the member key/value pair.
+
+		// Take into account a value can contain equal signs (=).
+		kv := strings.SplitN(parts[0], keyValueDelimiter, 2)
+		if len(kv) != 2 {
+			return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidMember, member)
+		}
+		// "Leading and trailing whitespaces are allowed but MUST be trimmed
+		// when converting the header into a data structure."
+		key = strings.TrimSpace(kv[0])
+		var err error
+		value, err = url.QueryUnescape(strings.TrimSpace(kv[1]))
+		if err != nil {
+			return newInvalidMember(), fmt.Errorf("%w: %q", err, value)
+		}
+		if !keyRe.MatchString(key) {
+			return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidKey, key)
+		}
+		if !valueRe.MatchString(value) {
+			return newInvalidMember(), fmt.Errorf("%w: %q", errInvalidValue, value)
+		}
+	default:
+		// This should never happen unless a developer has changed the string
+		// splitting somehow. Panic instead of failing silently and allowing
+		// the bug to slip past the CI checks.
+		panic("failed to parse baggage member")
+	}
+
+	return Member{key: key, value: value, properties: props, hasData: true}, nil
+}
+
+// validate ensures m conforms to the W3C Baggage specification, returning an
+// error otherwise.
+func (m Member) validate() error {
+	if !m.hasData {
+		return fmt.Errorf("%w: %q", errInvalidMember, m)
+	}
+
+	if !keyRe.MatchString(m.key) {
+		return fmt.Errorf("%w: %q", errInvalidKey, m.key)
+	}
+	if !valueRe.MatchString(m.value) {
+		return fmt.Errorf("%w: %q", errInvalidValue, m.value)
+	}
+	return m.properties.validate()
+}
+
+// Key returns the Member key.
+func (m Member) Key() string { return m.key }
+
+// Value returns the Member value.
+func (m Member) Value() string { return m.value }
+
+// Properties returns a copy of the Member properties.
+func (m Member) Properties() []Property { return m.properties.Copy() }
+
+// String encodes Member into a string compliant with the W3C Baggage
+// specification.
+func (m Member) String() string {
+	// A key is just an ASCII string, but a value is URL encoded UTF-8.
+	s := fmt.Sprintf("%s%s%s", m.key, keyValueDelimiter, url.QueryEscape(m.value))
+	if len(m.properties) > 0 {
+		s = fmt.Sprintf("%s%s%s", s, propertyDelimiter, m.properties.String())
+	}
+	return s
+}
+
+// Baggage is a list of baggage members representing the baggage-string as
+// defined by the W3C Baggage specification.
+type Baggage struct { //nolint:golint
+	list baggage.List
+}
+
+// New returns a new valid Baggage. It returns an error if it results in a
+// Baggage exceeding limits set in that specification.
+//
+// It expects all the provided members to have already been validated.
+func New(members ...Member) (Baggage, error) {
+	if len(members) == 0 {
+		return Baggage{}, nil
+	}
+
+	b := make(baggage.List)
+	for _, m := range members {
+		if !m.hasData {
+			return Baggage{}, errInvalidMember
+		}
+
+		// OpenTelemetry resolves duplicates by last-one-wins.
+		b[m.key] = baggage.Item{
+			Value:      m.value,
+			Properties: m.properties.asInternal(),
+		}
+	}
+
+	// Check member numbers after deduplication.
+	if len(b) > maxMembers {
+		return Baggage{}, errMemberNumber
+	}
+
+	bag := Baggage{b}
+	if n := len(bag.String()); n > maxBytesPerBaggageString {
+		return Baggage{}, fmt.Errorf("%w: %d", errBaggageBytes, n)
+	}
+
+	return bag, nil
+}
+
+// Parse attempts to decode a baggage-string from the passed string. It
+// returns an error if the input is invalid according to the W3C Baggage
+// specification.
+//
+// If there are duplicate list-members contained in baggage, the last one
+// defined (reading left-to-right) will be the only one kept. This diverges
+// from the W3C Baggage specification which allows duplicate list-members, but
+// conforms to the OpenTelemetry Baggage specification.
+func Parse(bStr string) (Baggage, error) {
+	if bStr == "" {
+		return Baggage{}, nil
+	}
+
+	if n := len(bStr); n > maxBytesPerBaggageString {
+		return Baggage{}, fmt.Errorf("%w: %d", errBaggageBytes, n)
+	}
+
+	b := make(baggage.List)
+	for _, memberStr := range strings.Split(bStr, listDelimiter) {
+		m, err := parseMember(memberStr)
+		if err != nil {
+			return Baggage{}, err
+		}
+		// OpenTelemetry resolves duplicates by last-one-wins.
+		b[m.key] = baggage.Item{
+			Value:      m.value,
+			Properties: m.properties.asInternal(),
+		}
+	}
+
+	// OpenTelemetry does not allow for duplicate list-members, but the W3C
+	// specification does. Now that we have deduplicated, ensure the baggage
+	// does not exceed list-member limits.
+	if len(b) > maxMembers {
+		return Baggage{}, errMemberNumber
+	}
+
+	return Baggage{b}, nil
+}
+
+// Member returns the baggage list-member identified by key.
+//
+// If there is no list-member matching the passed key the returned Member will
+// be a zero-value Member.
+// The returned member is not validated, as we assume the validation happened
+// when it was added to the Baggage.
+func (b Baggage) Member(key string) Member {
+	v, ok := b.list[key]
+	if !ok {
+		// We do not need to worry about distinguishing between the situation
+		// where a zero-valued Member is included in the Baggage because a
+		// zero-valued Member is invalid according to the W3C Baggage
+		// specification (it has an empty key).
+		return newInvalidMember()
+	}
+
+	return Member{
+		key:        key,
+		value:      v.Value,
+		properties: fromInternalProperties(v.Properties),
+	}
+}
+
+// Members returns all the baggage list-members.
+// The order of the returned list-members does not have significance.
+//
+// The returned members are not validated, as we assume the validation happened
+// when they were added to the Baggage.
+func (b Baggage) Members() []Member {
+	if len(b.list) == 0 {
+		return nil
+	}
+
+	members := make([]Member, 0, len(b.list))
+	for k, v := range b.list {
+		members = append(members, Member{
+			key:        k,
+			value:      v.Value,
+			properties: fromInternalProperties(v.Properties),
+		})
+	}
+	return members
+}
+
+// SetMember returns a copy the Baggage with the member included. If the
+// baggage contains a Member with the same key the existing Member is
+// replaced.
+//
+// If member is invalid according to the W3C Baggage specification, an error
+// is returned with the original Baggage.
+func (b Baggage) SetMember(member Member) (Baggage, error) {
+	if !member.hasData {
+		return b, errInvalidMember
+	}
+
+	n := len(b.list)
+	if _, ok := b.list[member.key]; !ok {
+		n++
+	}
+	list := make(baggage.List, n)
+
+	for k, v := range b.list {
+		// Do not copy if we are just going to overwrite.
+		if k == member.key {
+			continue
+		}
+		list[k] = v
+	}
+
+	list[member.key] = baggage.Item{
+		Value:      member.value,
+		Properties: member.properties.asInternal(),
+	}
+
+	return Baggage{list: list}, nil
+}
+
+// DeleteMember returns a copy of the Baggage with the list-member identified
+// by key removed.
+func (b Baggage) DeleteMember(key string) Baggage {
+	n := len(b.list)
+	if _, ok := b.list[key]; ok {
+		n--
+	}
+	list := make(baggage.List, n)
+
+	for k, v := range b.list {
+		if k == key {
+			continue
+		}
+		list[k] = v
+	}
+
+	return Baggage{list: list}
+}
+
+// Len returns the number of list-members in the Baggage.
+func (b Baggage) Len() int {
+	return len(b.list)
+}
+
+// String encodes Baggage into a string compliant with the W3C Baggage
+// specification. The returned string will be invalid if the Baggage contains
+// any invalid list-members.
+func (b Baggage) String() string {
+	members := make([]string, 0, len(b.list))
+	for k, v := range b.list {
+		members = append(members, Member{
+			key:        k,
+			value:      v.Value,
+			properties: fromInternalProperties(v.Properties),
+		}.String())
+	}
+	return strings.Join(members, listDelimiter)
+}