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README.md

+A very simple crawler
+=====================
+
+This tool can crawl a bunch of URLs for HTML content, and save the
+results in a nice WARC file. It has little control over its traffic,
+save for a limit on concurrent outbound requests. Its main purpose is
+to quickly and efficiently save websites for archival purposes.
+
+The *crawl* tool saves its state in a database, so it can be safely
+interrupted and restarted without issues.
+
+# Installation
+
+From this source directory (checked out in the correct place in your
+GOPATH), run:
+
+    $ go install cmd/crawl
+
+# Usage
+
+Just run *crawl* by passing the URLs of the websites you want to crawl
+as arguments on the command line:
+
+    $ crawl http://example.com/
+
+By default, the tool will store the output WARC file and its own
+database in the current directory. This can be controlled with the
+*--output* and *--state* command-line options.
+
+The crawling scope is controlled with a set of overlapping checks:
+
+* URL scheme must be one of *http* or *https*
+* URL must have one of the seeds as a prefix (an eventual *www.*
+  prefix is implicitly ignored)
+* maximum crawling depth can be controlled with the *--depth* option
+* resources related to a page (CSS, JS, etc) will always be fetched,
+  even if on external domains, if the *--include-related* option is
+  specified
+
+If the program is interrupted, running it again with the same command
+line from the same directory will cause it to resume crawling from
+where it stopped. At the end of a successful crawl, the database will
+be removed (unless you specify the *--keep* option, for debugging
+purposes).