MM-28249 Auto follow threads (#15878)

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

app/app_iface.go

@@ -685,6 +685,7 @@ type AppIface interface {
 	GetTeamsForUser(userId string) ([]*model.Team, *model.AppError)
 	GetTeamsUnreadForUser(excludeTeamId string, userId string) ([]*model.TeamUnread, *model.AppError)
 	GetTermsOfService(id string) (*model.TermsOfService, *model.AppError)
+	GetThreadMembershipsForUser(userId string) ([]*model.ThreadMembership, error)
 	GetUploadSession(uploadId string) (*model.UploadSession, *model.AppError)
 	GetUploadSessionsForUser(userId string) ([]*model.UploadSession, *model.AppError)
 	GetUser(userId string) (*model.User, *model.AppError)

app/notification.go

@@ -159,20 +159,37 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 
 	mentionedUsersList := make([]string, 0, len(mentions.Mentions))
 	updateMentionChans := []chan *model.AppError{}
+	mentionAutofollowChans := []chan *model.AppError{}
+
+	// for each mention, make sure to update thread autofollow
+	for id := range mentions.Mentions {
+		mac := make(chan *model.AppError, 1)
+		go func(userId string) {
+			defer close(mac)
+			if *a.Config().ServiceSettings.ThreadAutoFollow && post.RootId != "" {
+				nErr := a.Srv().Store.Thread().CreateMembershipIfNeeded(userId, post.RootId)
+				if nErr != nil {
+					mac <- model.NewAppError("SendNotifications", "app.channel.autofollow.app_error", nil, nErr.Error(), http.StatusInternalServerError)
+					return
+				}
+			}
+			mac <- nil
+		}(id)
+		mentionAutofollowChans = append(mentionAutofollowChans, mac)
+	}
 
 	for id := range mentions.Mentions {
 		mentionedUsersList = append(mentionedUsersList, id)
 
 		umc := make(chan *model.AppError, 1)
 		go func(userId string) {
+			defer close(umc)
 			nErr := a.Srv().Store.Channel().IncrementMentionCount(post.ChannelId, userId)
 			if nErr != nil {
 				umc <- model.NewAppError("SendNotifications", "app.channel.increment_mention_count.app_error", nil, nErr.Error(), http.StatusInternalServerError)
-			} else {
-				umc <- nil
+				return
 			}
-
-			close(umc)
+			umc <- nil
 		}(id)
 		updateMentionChans = append(updateMentionChans, umc)
 	}
@@ -254,6 +271,17 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 		}
 	}
 
+	// Log the problems that might have occurred while auto following the thread
+	for _, mac := range mentionAutofollowChans {
+		if err := <-mac; err != nil {
+			mlog.Warn(
+				"Failed to update thread autofollow from mention",
+				mlog.String("post_id", post.Id),
+				mlog.String("channel_id", post.ChannelId),
+				mlog.Err(err),
+			)
+		}
+	}
 	sendPushNotifications := false
 	if *a.Config().EmailSettings.SendPushNotifications {
 		pushServer := *a.Config().EmailSettings.PushNotificationServer

app/opentracing/opentracing_layer.go

@@ -8397,6 +8397,28 @@ func (a *OpenTracingAppLayer) GetTermsOfService(id string) (*model.TermsOfServic
 	return resultVar0, resultVar1
 }
 
+func (a *OpenTracingAppLayer) GetThreadMembershipsForUser(userId string) ([]*model.ThreadMembership, error) {
+	origCtx := a.ctx
+	span, newCtx := tracing.StartSpanWithParentByContext(a.ctx, "app.GetThreadMembershipsForUser")
+
+	a.ctx = newCtx
+	a.app.Srv().Store.SetContext(newCtx)
+	defer func() {
+		a.app.Srv().Store.SetContext(origCtx)
+		a.ctx = origCtx
+	}()
+
+	defer span.Finish()
+	resultVar0, resultVar1 := a.app.GetThreadMembershipsForUser(userId)
+
+	if resultVar1 != nil {
+		span.LogFields(spanlog.Error(resultVar1))
+		ext.Error.Set(span, true)
+	}
+
+	return resultVar0, resultVar1
+}
+
 func (a *OpenTracingAppLayer) GetTotalUsersStats(viewRestrictions *model.ViewUsersRestrictions) (*model.UsersStats, *model.AppError) {
 	origCtx := a.ctx
 	span, newCtx := tracing.StartSpanWithParentByContext(a.ctx, "app.GetTotalUsersStats")

app/post.go

@@ -443,6 +443,12 @@ func (a *App) handlePostEvents(post *model.Post, user *model.User, channel *mode
 		return err
 	}
 
+	if *a.Config().ServiceSettings.ThreadAutoFollow && post.RootId != "" {
+		if err := a.Srv().Store.Thread().CreateMembershipIfNeeded(post.UserId, post.RootId); err != nil {
+			return err
+		}
+	}
+
 	if post.Type != model.POST_AUTO_RESPONDER { // don't respond to an auto-responder
 		a.Srv().Go(func() {
 			_, err := a.SendAutoResponseIfNecessary(channel, user)
@@ -1450,3 +1456,7 @@ func isPostMention(user *model.User, post *model.Post, keywords map[string][]str
 
 	return false
 }
+
+func (a *App) GetThreadMembershipsForUser(userId string) ([]*model.ThreadMembership, error) {
+	return a.Srv().Store.Thread().GetMembershipsForUser(userId)
+}

app/post_test.go

@@ -1846,3 +1846,60 @@ func TestFillInPostProps(t *testing.T) {
 		assert.Equal(t, post1.Props, model.StringInterface{"disable_group_highlight": true})
 	})
 }
+
+func TestThreadMembership(t *testing.T) {
+	t.Run("should update memberships for conversation participants", func(t *testing.T) {
+		th := Setup(t).InitBasic()
+		defer th.TearDown()
+
+		user1 := th.BasicUser
+		user2 := th.BasicUser2
+
+		channel := th.CreateChannel(th.BasicTeam)
+		th.AddUserToChannel(user2, channel)
+
+		postRoot, err := th.App.CreatePost(&model.Post{
+			UserId:    user1.Id,
+			ChannelId: channel.Id,
+			Message:   "root post",
+		}, channel, false, true)
+		require.Nil(t, err)
+
+		_, err = th.App.CreatePost(&model.Post{
+			UserId:    user1.Id,
+			ChannelId: channel.Id,
+			RootId:    postRoot.Id,
+			Message:   fmt.Sprintf("@%s", user2.Username),
+		}, channel, false, true)
+		require.Nil(t, err)
+
+		// first user should now be part of the thread since they replied to a post
+		memberships, err2 := th.App.GetThreadMembershipsForUser(user1.Id)
+		require.Nil(t, err2)
+		require.Len(t, memberships, 1)
+		// second user should also be part of a thread since they were mentioned
+		memberships, err2 = th.App.GetThreadMembershipsForUser(user2.Id)
+		require.Nil(t, err2)
+		require.Len(t, memberships, 1)
+
+		post2, err := th.App.CreatePost(&model.Post{
+			UserId:    user2.Id,
+			ChannelId: channel.Id,
+			Message:   "second post",
+		}, channel, false, true)
+		require.Nil(t, err)
+
+		_, err = th.App.CreatePost(&model.Post{
+			UserId:    user2.Id,
+			ChannelId: channel.Id,
+			RootId:    post2.Id,
+			Message:   fmt.Sprintf("@%s", user1.Username),
+		}, channel, false, true)
+		require.Nil(t, err)
+
+		// first user should now be part of two threads
+		memberships, err2 = th.App.GetThreadMembershipsForUser(user1.Id)
+		require.Nil(t, err2)
+		require.Len(t, memberships, 2)
+	})
+}