Enable tag drift 02

command/agent/agent.go

@@ -290,6 +290,9 @@ func (a *Agent) consulConfig() *consul.Config {
 	if a.config.SessionTTLMinRaw != "" {
 		base.SessionTTLMin = a.config.SessionTTLMin
 	}
+	if a.config.EnableTagDrift {
+		base.EnableTagDrift = true
+	}
 
 	// Format the build string
 	revision := a.config.Revision

command/agent/command.go

@@ -109,6 +109,8 @@ func (c *Command) readConfig() *Config {
 		"number of retries for joining -wan")
 	cmdFlags.StringVar(&retryIntervalWan, "retry-interval-wan", "",
 		"interval between join -wan attempts")
+	cmdFlags.BoolVar(&cmdConfig.EnableTagDrift, "enable_tag_drift", false,
+		"enable tag drift - ignore tags during anti-entropy")
 
 	if err := cmdFlags.Parse(c.args); err != nil {
 		return nil
@@ -745,6 +747,7 @@ AFTER_MIGRATE:
 	c.Ui.Info(fmt.Sprintf("Gossip encrypt: %v, RPC-TLS: %v, TLS-Incoming: %v",
 		gossipEncrypted, config.VerifyOutgoing, config.VerifyIncoming))
 	c.Ui.Info(fmt.Sprintf("         Atlas: %s", atlas))
+	c.Ui.Info(fmt.Sprintf("EnableTagDrift: %v", config.EnableTagDrift))
 
 	// Enable log streaming
 	c.Ui.Info("")

command/agent/config.go

@@ -395,6 +395,10 @@ type Config struct {
 	// Minimum Session TTL
 	SessionTTLMin    time.Duration `mapstructure:"-"`
 	SessionTTLMinRaw string        `mapstructure:"session_ttl_min"`
+
+	// EnableTagDrift when true will inhibit comparison
+	// of service tags during anti-entropy
+	EnableTagDrift bool `mapstructure:"enable_tag_drift"`
 }
 
 // UnixSocketPermissions contains information about a unix socket, and
@@ -1068,6 +1072,9 @@ func MergeConfig(a, b *Config) *Config {
 			result.HTTPAPIResponseHeaders[field] = value
 		}
 	}
+	if b.EnableTagDrift {
+		result.EnableTagDrift = true
+	}
 
 	// Copy the start join addresses
 	result.StartJoin = make([]string, 0, len(a.StartJoin)+len(b.StartJoin))

command/agent/config_test.go

@@ -555,6 +555,10 @@ func TestDecodeConfig(t *testing.T) {
 		t.Fatalf("bad: %#v", config)
 	}
 
+	if config.EnableTagDrift {
+		t.Fatalf("EnableTagDrift should be false by default.  Actual config: %#v", config)
+	}
+
 	// ACLs
 	input = `{"acl_token": "1234", "acl_datacenter": "dc2",
 	"acl_ttl": "60s", "acl_down_policy": "deny",
@@ -1214,6 +1218,7 @@ func TestMergeConfig(t *testing.T) {
 			RPC:        &net.TCPAddr{},
 			RPCRaw:     "127.0.0.5:1233",
 		},
+		EnableTagDrift: false,
 	}
 
 	c := MergeConfig(a, b)

command/agent/local.go

@@ -378,6 +378,13 @@ func (l *localState) setSyncState() error {
 			continue
 		}
 
+		if l.config.EnableTagDrift {
+			l.logger.Printf("[DEBUG] Tag drift enabled.")
+			existing.Tags = service.Tags
+		} else {
+			l.logger.Printf("[DEBUG] Tag drift disabled.")
+		}
+
 		// If our definition is different, we need to update it
 		equal := reflect.DeepEqual(existing, service)
 		l.serviceStatus[id] = syncStatus{inSync: equal}

consul/config.go

@@ -203,6 +203,10 @@ type Config struct {
 	// UserEventHandler callback can be used to handle incoming
 	// user events. This function should not block.
 	UserEventHandler func(serf.UserEvent)
+
+	// EnableTagDrift when true will inhibit comparison
+	// of service tags during anti-entropy
+	EnableTagDrift bool
 }
 
 // CheckVersion is used to check if the ProtocolVersion is valid