MM-27493 Shared channels (MVP) (#17301)

Remote Cluster Service
- provides ability for multiple Mattermost cluster instances to create a trusted connection with each other and exchange messages
- trusted connections are managed via slash commands (for now)
- facilitates features requiring inter-cluster communication, such as Shared Channels
Shared Channels Service
- provides ability to shared channels between one or more Mattermost cluster instances (using trusted connection)
- sharing/unsharing of channels is managed via slash commands (for now)

einterfaces/metrics.go

@@ -66,6 +66,13 @@ type MetricsInterface interface {
 	ObserveEnabledUsers(users int64)
 	GetLoggerMetricsCollector() logr.MetricsCollector
 
+	IncrementRemoteClusterMsgSentCounter(remoteID string)
+	IncrementRemoteClusterMsgReceivedCounter(remoteID string)
+	IncrementRemoteClusterMsgErrorsCounter(remoteID string, timeout bool)
+	ObserveRemoteClusterPingDuration(remoteID string, elapsed float64)
+	ObserveRemoteClusterClockSkew(remoteID string, skew float64)
+	IncrementRemoteClusterConnStateChangeCounter(remoteID string, online bool)
+
 	IncrementJobActive(jobType string)
 	DecrementJobActive(jobType string)
 

einterfaces/mocks/MetricsInterface.go

@@ -180,6 +180,26 @@ func (_m *MetricsInterface) IncrementPostsSearchCounter() {
 	_m.Called()
 }
 
+// IncrementRemoteClusterConnStateChangeCounter provides a mock function with given fields: remoteID, online
+func (_m *MetricsInterface) IncrementRemoteClusterConnStateChangeCounter(remoteID string, online bool) {
+	_m.Called(remoteID, online)
+}
+
+// IncrementRemoteClusterMsgErrorsCounter provides a mock function with given fields: remoteID, timeout
+func (_m *MetricsInterface) IncrementRemoteClusterMsgErrorsCounter(remoteID string, timeout bool) {
+	_m.Called(remoteID, timeout)
+}
+
+// IncrementRemoteClusterMsgReceivedCounter provides a mock function with given fields: remoteID
+func (_m *MetricsInterface) IncrementRemoteClusterMsgReceivedCounter(remoteID string) {
+	_m.Called(remoteID)
+}
+
+// IncrementRemoteClusterMsgSentCounter provides a mock function with given fields: remoteID
+func (_m *MetricsInterface) IncrementRemoteClusterMsgSentCounter(remoteID string) {
+	_m.Called(remoteID)
+}
+
 // IncrementUserIndexCounter provides a mock function with given fields:
 func (_m *MetricsInterface) IncrementUserIndexCounter() {
 	_m.Called()
@@ -255,6 +275,16 @@ func (_m *MetricsInterface) ObservePostsSearchDuration(elapsed float64) {
 	_m.Called(elapsed)
 }
 
+// ObserveRemoteClusterClockSkew provides a mock function with given fields: remoteID, skew
+func (_m *MetricsInterface) ObserveRemoteClusterClockSkew(remoteID string, skew float64) {
+	_m.Called(remoteID, skew)
+}
+
+// ObserveRemoteClusterPingDuration provides a mock function with given fields: remoteID, elapsed
+func (_m *MetricsInterface) ObserveRemoteClusterPingDuration(remoteID string, elapsed float64) {
+	_m.Called(remoteID, elapsed)
+}
+
 // ObserveStoreMethodDuration provides a mock function with given fields: method, success, elapsed
 func (_m *MetricsInterface) ObserveStoreMethodDuration(method string, success string, elapsed float64) {
 	_m.Called(method, success, elapsed)