slight refactoring of the icecast configuration to increase object reuse

api.go

@@ -2,6 +2,8 @@ package radioai
 
 import (
 	"bytes"
+	"crypto/rand"
+	"encoding/base64"
 	"encoding/json"
 	"errors"
 	"strings"
@@ -119,3 +121,10 @@ func (r *RadioAPI) GetMasterAddr() (string, error) {
 	}
 	return response[0].Value, nil
 }
+
+// GeneratePassword returns a new random password.
+func GeneratePassword() string {
+	b := make([]byte, 6)
+	rand.Read(b)
+	return base64.StdEncoding.EncodeToString(b)
+}

cmd/radioctl/radioctl.go

 package main
 
 import (
-	"crypto/rand"
-	"encoding/base64"
 	"flag"
 	"fmt"
 	"hash/crc32"
@@ -104,12 +102,6 @@ func generateUsername(path string) string {
 	return fmt.Sprintf("source%d", crc32.ChecksumIEEE([]byte(path)))
 }
 
-func generatePassword() string {
-	b := make([]byte, 6)
-	rand.Read(b)
-	return base64.StdEncoding.EncodeToString(b)
-}
-
 func createMount(args []string) {
 	path := args[0]
 	if !strings.HasPrefix(path, "/") {
@@ -125,7 +117,7 @@ func createMount(args []string) {
 
 	// Create the new mount, randomly generate source authentication.
 	username := generateUsername(path)
-	password := generatePassword()
+	password := radioai.GeneratePassword()
 	m := &radioai.Mount{
 		Name:     path,
 		Username: username,

icecast.go

@@ -6,16 +6,18 @@ import (
 )
 
 type IcecastController struct {
-	PublicIp       string
-	ConfigFile     string
-	InitScript     string
+	PublicIp   string
+	ConfigFile string
+	InitScript string
+	config     *icecastConfig
 }
 
 func NewIcecastController(publicIp string) *IcecastController {
 	return &IcecastController{
-		PublicIp:       publicIp,
-		ConfigFile:     "/etc/icecast2/icecast.conf",
-		InitScript:     "/etc/init.d/icecast2",
+		PublicIp:   publicIp,
+		ConfigFile: "/etc/icecast2/icecast.conf",
+		InitScript: "/etc/init.d/icecast2",
+		config:     newIcecastConfig(publicIp),
 	}
 }
 
@@ -31,8 +33,8 @@ func (ic *IcecastController) Update(conf *ClusterConfig, isMaster bool, masterAd
 	tmpf := ic.ConfigFile + ".tmp"
 	defer os.Remove(tmpf)
 
-	iconfig := NewIcecastConfig(conf, ic.PublicIp, isMaster, masterAddr)
-	if err := iconfig.EncodeToFile(tmpf); err != nil {
+	ic.config.Update(conf, isMaster, masterAddr)
+	if err := ic.config.EncodeToFile(tmpf); err != nil {
 		return err
 	}
 

icecast_config.go

@@ -79,7 +79,7 @@ type iceMountConfig struct {
 	OnDisconnect     string `xml:"on-disconnect,omitempty"`
 }
 
-type IcecastConfig struct {
+type icecastConfig struct {
 	XMLName   xml.Name
 	Limits    iceLimitsConfig         `xml:"limits"`
 	Auth      iceAuthenticationConfig `xml:"authentication"`
@@ -93,11 +93,13 @@ type IcecastConfig struct {
 	Mounts    []iceMountConfig        `xml:"mount"`
 }
 
-func defaultDebianConfig() *IcecastConfig {
-	sourcePw := "x"
-	adminPw := "password"
+func defaultDebianConfig(publicIp string) *icecastConfig {
+	// Pick some random passwords on startup. We don't use them,
+	// but icecast is happier if they're set.
+	sourcePw := GeneratePassword()
+	adminPw := GeneratePassword()
 
-	return &IcecastConfig{
+	return &icecastConfig{
 		XMLName: xml.Name{"", "icecast"},
 		Limits: iceLimitsConfig{
 			Clients:        maxClients,
@@ -115,6 +117,7 @@ func defaultDebianConfig() *IcecastConfig {
 			AdminUser:      "admin",
 			AdminPassword:  adminPw,
 		},
+		Hostname: publicIp,
 		Fileserve: 1,
 		Paths: icePathsConfig{
 			Basedir:   "/usr/share/icecast2",
@@ -133,12 +136,14 @@ func defaultDebianConfig() *IcecastConfig {
 			{"0.0.0.0", baseHttpPort, 0},
 			{"0.0.0.0", shoutHttpPort, 1},
 		},
-		Relays: []iceRelayConfig{},
-		Mounts: []iceMountConfig{},
 	}
 }
 
-func (c *IcecastConfig) Encode() ([]byte, error) {
+func newIcecastConfig(publicIp string) *icecastConfig {
+	return defaultDebianConfig(publicIp)
+}
+
+func (c *icecastConfig) Encode() ([]byte, error) {
 	var buf bytes.Buffer
 
 	output, err := xml.MarshalIndent(c, "", "  ")
@@ -152,7 +157,7 @@ func (c *IcecastConfig) Encode() ([]byte, error) {
 	return buf.Bytes(), nil
 }
 
-func (c *IcecastConfig) EncodeToFile(path string) error {
+func (c *icecastConfig) EncodeToFile(path string) error {
 	file, err := os.Create(path)
 	if err != nil {
 		return err
@@ -196,15 +201,20 @@ func mountToRelay(masterAddr string, m *Mount) iceRelayConfig {
 	}
 }
 
-func NewIcecastConfig(config *ClusterConfig, publicIp string, isMaster bool, masterAddr string) *IcecastConfig {
-	iconf := defaultDebianConfig()
-	iconf.Hostname = publicIp
-	for _, m := range config.ListMounts() {
-		if isMaster {
-			iconf.Mounts = append(iconf.Mounts, mountToConfig(m))
-		} else {
-			iconf.Relays = append(iconf.Relays, mountToRelay(masterAddr, m))
+func (ic *icecastConfig) Update(config *ClusterConfig, isMaster bool, masterAddr string) {
+	ic.Mounts = nil
+	ic.Relays = nil
+	if isMaster {
+		mounts := make([]iceMountConfig, 0)
+		for _, m := range config.ListMounts() {
+			mounts = append(mounts, mountToConfig(m))
+		}
+		ic.Mounts = mounts
+	} else {
+		relays := make([]iceRelayConfig, 0)
+		for _, m := range config.ListMounts() {
+			relays = append(relays, mountToRelay(masterAddr, m))
 		}
+		ic.Relays = relays
 	}
-	return iconf
 }

icecast_config_test.go

@@ -15,7 +15,8 @@ func TestIcecastConfig(t *testing.T) {
 	c.setMount(mount)
 
 	// Test a relay config.
-	ice := NewIcecastConfig(c, "1.2.3.4", false, "2.3.4.5")
+	ice := newIcecastConfig("1.2.3.4")
+	ice.Update(c, false, "2.3.4.5")
 	output, err := ice.Encode()
 	if err != nil {
 		t.Fatal(err)
@@ -29,7 +30,8 @@ func TestIcecastConfig(t *testing.T) {
 	}
 
 	// Test a master config.
-	ice = NewIcecastConfig(c, "1.2.3.4", true, "2.3.4.5")
+	ice = newIcecastConfig("1.2.3.4")
+	ice.Update(c, true, "2.3.4.5")
 	output, err = ice.Encode()
 	if err != nil {
 		t.Fatal(err)

node.go

@@ -110,7 +110,13 @@ func (w *ConfigSyncer) syncer() {
 				continue
 			}
 
+			// Update the 'last seen' index, so that if
+			// the Watcher dies, it knows where to start
+			// from and we do not have to download the
+			// full configuration again.
 			w.index = response.Index
+
+			// Trigger an update.
 			trigger(w.upch)
 
 		case <-w.stop: