[MM-54757] Stop broadcasting channel_deleted/channel_restored messages from private channels to non-members (#27001)

* [MM-54757] Stop broadcasting channel_deleted/channel_restored messages from private channels to non-members

* Remove unnecessary return

---------

Co-authored-by: Mattermost Build <build@mattermost.com>

server/channels/app/channel.go

@@ -764,7 +764,12 @@ func (a *App) RestoreChannel(c request.CTX, channel *model.Channel, userID strin
 	channel.DeleteAt = 0
 	a.Srv().Platform().InvalidateCacheForChannel(channel)
 
-	message := model.NewWebSocketEvent(model.WebsocketEventChannelRestored, channel.TeamId, "", "", nil, "")
+	var message *model.WebSocketEvent
+	if channel.Type == model.ChannelTypeOpen {
+		message = model.NewWebSocketEvent(model.WebsocketEventChannelRestored, channel.TeamId, "", "", nil, "")
+	} else {
+		message = model.NewWebSocketEvent(model.WebsocketEventChannelRestored, "", channel.Id, "", nil, "")
+	}
 	message.Add("channel_id", channel.Id)
 	a.Publish(message)
 
@@ -1497,7 +1502,12 @@ func (a *App) DeleteChannel(c request.CTX, channel *model.Channel, userID string
 
 	a.Srv().Platform().InvalidateCacheForChannel(channel)
 
-	message := model.NewWebSocketEvent(model.WebsocketEventChannelDeleted, channel.TeamId, "", "", nil, "")
+	var message *model.WebSocketEvent
+	if channel.Type == model.ChannelTypeOpen {
+		message = model.NewWebSocketEvent(model.WebsocketEventChannelDeleted, channel.TeamId, "", "", nil, "")
+	} else {
+		message = model.NewWebSocketEvent(model.WebsocketEventChannelDeleted, "", channel.Id, "", nil, "")
+	}
 	message.Add("channel_id", channel.Id)
 	message.Add("delete_at", deleteAt)
 	a.Publish(message)
@@ -3078,8 +3088,13 @@ func (a *App) PermanentDeleteChannel(c request.CTX, channel *model.Channel) *mod
 	}
 
 	a.Srv().Platform().InvalidateCacheForChannel(channel)
-	message := model.NewWebSocketEvent(model.WebsocketEventChannelDeleted, channel.TeamId, "", "", nil, "")
 
+	var message *model.WebSocketEvent
+	if channel.Type == model.ChannelTypeOpen {
+		message = model.NewWebSocketEvent(model.WebsocketEventChannelDeleted, channel.TeamId, "", "", nil, "")
+	} else {
+		message = model.NewWebSocketEvent(model.WebsocketEventChannelDeleted, "", channel.Id, "", nil, "")
+	}
 	message.Add("channel_id", channel.Id)
 	message.Add("delete_at", deleteAt)
 	a.Publish(message)

server/channels/app/channel_test.go

@@ -2854,3 +2854,101 @@ func TestPatchChannelMembersNotifyProps(t *testing.T) {
 		assert.NotNil(t, appErr)
 	})
 }
+
+func TestDeleteChannel(t *testing.T) {
+	th := Setup(t).InitBasic()
+	defer th.TearDown()
+
+	t.Run("should send the correct websocket events", func(t *testing.T) {
+		user1 := th.CreateUser()
+		user2 := th.CreateUser()
+
+		channel1 := th.CreateChannel(th.Context, th.BasicTeam)
+		channel2 := th.CreatePrivateChannel(th.Context, th.BasicTeam)
+
+		th.LinkUserToTeam(user1, th.BasicTeam)
+		th.LinkUserToTeam(user2, th.BasicTeam)
+		th.AddUserToChannel(user1, channel1)
+		th.AddUserToChannel(user1, channel2)
+
+		eventTypesFilter := []model.WebsocketEventType{model.WebsocketEventChannelDeleted}
+
+		messages1, closeWS1 := connectFakeWebSocket(t, th, user1.Id, "", eventTypesFilter)
+		defer closeWS1()
+		messages2, closeWS2 := connectFakeWebSocket(t, th, user2.Id, "", eventTypesFilter)
+		defer closeWS2()
+
+		err := th.App.DeleteChannel(th.Context, channel1, "")
+		require.Nil(t, err)
+
+		received := <-messages1
+		assert.Equal(t, model.WebsocketEventChannelDeleted, received.EventType())
+		received = <-messages2
+		assert.Equal(t, model.WebsocketEventChannelDeleted, received.EventType())
+
+		err = th.App.DeleteChannel(th.Context, channel2, "")
+		require.Nil(t, err)
+
+		select {
+		case shouldNotReceive := <-messages2:
+			assert.NotEqual(t, model.WebsocketEventChannelDeleted, shouldNotReceive.EventType())
+		case <-time.After(2 * time.Second):
+		}
+
+		received = <-messages1
+		assert.Equal(t, model.WebsocketEventChannelDeleted, received.EventType())
+	})
+}
+
+func TestRestoreChannel(t *testing.T) {
+	th := Setup(t).InitBasic()
+	defer th.TearDown()
+
+	t.Run("should send the correct websocket events", func(t *testing.T) {
+		user1 := th.CreateUser()
+		user2 := th.CreateUser()
+
+		channel1 := th.CreateChannel(th.Context, th.BasicTeam)
+		channel2 := th.CreatePrivateChannel(th.Context, th.BasicTeam)
+
+		th.LinkUserToTeam(user1, th.BasicTeam)
+		th.LinkUserToTeam(user2, th.BasicTeam)
+		th.AddUserToChannel(user1, channel1)
+		th.AddUserToChannel(user1, channel2)
+
+		err := th.App.DeleteChannel(th.Context, channel1, "")
+		require.Nil(t, err)
+		err = th.App.DeleteChannel(th.Context, channel2, "")
+		require.Nil(t, err)
+
+		channel1.DeleteAt = time.Now().UnixMilli()
+		channel2.DeleteAt = time.Now().UnixMilli()
+
+		eventTypesFilter := []model.WebsocketEventType{model.WebsocketEventChannelRestored}
+
+		messages1, closeWS1 := connectFakeWebSocket(t, th, user1.Id, "", eventTypesFilter)
+		defer closeWS1()
+		messages2, closeWS2 := connectFakeWebSocket(t, th, user2.Id, "", eventTypesFilter)
+		defer closeWS2()
+
+		_, err = th.App.RestoreChannel(th.Context, channel1, "")
+		require.Nil(t, err)
+
+		received := <-messages1
+		assert.Equal(t, model.WebsocketEventChannelRestored, received.EventType())
+		received = <-messages2
+		assert.Equal(t, model.WebsocketEventChannelRestored, received.EventType())
+
+		_, err = th.App.RestoreChannel(th.Context, channel2, "")
+		require.Nil(t, err)
+
+		select {
+		case shouldNotReceive := <-messages2:
+			assert.NotEqual(t, model.WebsocketEventChannelRestored, shouldNotReceive.EventType())
+		case <-time.After(2 * time.Second):
+		}
+
+		received = <-messages1
+		assert.Equal(t, model.WebsocketEventChannelRestored, received.EventType())
+	})
+}