Integrate auth.AccessController into registry app

This changeset integrates the AccessController into the main registry app. This
includes support for configuration and a test implementation, called "silly"
auth. Auth is only enabled if the configuration is present but takes measure to
ensure that configuration errors don't allow the appserver to start with open
access.

configuration/configuration_test.go

@@ -29,6 +29,12 @@ var configStruct = Configuration{
 			"port":      42,
 		},
 	},
+	Auth: Auth{
+		"silly": Parameters{
+			"realm":   "silly",
+			"service": "silly",
+		},
+	},
 	Reporting: Reporting{
 		Bugsnag: BugsnagReporting{
 			APIKey: "BugsnagApiKey",
@@ -51,6 +57,10 @@ storage:
     secretkey: SUPERSECRET
     host: ~
     port: 42
+auth:
+  silly:
+    realm: silly
+    service: silly
 reporting:
   bugsnag:
     apikey: BugsnagApiKey
@@ -62,6 +72,10 @@ var inmemoryConfigYamlV0_1 = `
 version: 0.1
 loglevel: info
 storage: inmemory
+auth:
+  silly:
+    realm: silly
+    service: silly
 `
 
 type ConfigSuite struct {
@@ -113,10 +127,13 @@ func (suite *ConfigSuite) TestParseIncomplete(c *C) {
 	c.Assert(err, NotNil)
 
 	suite.expectedConfig.Storage = Storage{"filesystem": Parameters{"rootdirectory": "/tmp/testroot"}}
+	suite.expectedConfig.Auth = Auth{"silly": Parameters{"realm": "silly"}}
 	suite.expectedConfig.Reporting = Reporting{}
 
 	os.Setenv("REGISTRY_STORAGE", "filesystem")
 	os.Setenv("REGISTRY_STORAGE_FILESYSTEM_ROOTDIRECTORY", "/tmp/testroot")
+	os.Setenv("REGISTRY_AUTH", "silly")
+	os.Setenv("REGISTRY_AUTH_SILLY_REALM", "silly")
 
 	config, err := Parse(bytes.NewReader([]byte(incompleteConfigYaml)))
 	c.Assert(err, IsNil)
@@ -259,5 +276,10 @@ func copyConfig(config Configuration) *Configuration {
 		NewRelic: NewRelicReporting{config.Reporting.NewRelic.LicenseKey, config.Reporting.NewRelic.Name},
 	}
 
+	configCopy.Auth = Auth{config.Auth.Type(): Parameters{}}
+	for k, v := range config.Auth.Parameters() {
+		configCopy.Auth.setParameter(k, v)
+	}
+
 	return configCopy
 }