#4755 Combining consecutive user join/leave system messages to single message and few other changes. (#5945)

fix 7 and 8

remove @ at "{username} joined the channel"

refactor and update test

api/post_test.go

@@ -394,7 +394,7 @@ func TestUpdatePost(t *testing.T) {
 		}
 	}
 
-	post3 := &model.Post{ChannelId: channel1.Id, Message: "zz" + model.NewId() + "a", Type: model.POST_JOIN_LEAVE}
+	post3 := &model.Post{ChannelId: channel1.Id, Message: "zz" + model.NewId() + "a", Type: model.POST_HEADER_CHANGE}
 	rpost3, err := Client.CreatePost(post3)
 	if err != nil {
 		t.Fatal(err)

api4/post_test.go

@@ -359,7 +359,7 @@ func TestUpdatePost(t *testing.T) {
 		t.Fatal("failed to updates")
 	}
 
-	post2 := &model.Post{ChannelId: channel.Id, Message: "zz" + model.NewId() + "a", Type: model.POST_JOIN_LEAVE}
+	post2 := &model.Post{ChannelId: channel.Id, Message: "zz" + model.NewId() + "a", Type: model.POST_HEADER_CHANGE}
 	rpost2, resp := Client.CreatePost(post2)
 	CheckNoError(t, resp)
 

app/channel.go

@@ -897,19 +897,75 @@ func JoinChannel(channel *model.Channel, userId string) *model.AppError {
 	return nil
 }
 
-func postJoinChannelMessage(user *model.User, channel *model.Channel) *model.AppError {
+func createUserActivitySystemMessage(channel *model.Channel, user *model.User, otherUsername, messageType, message string) *model.AppError {
+	props := model.StringInterface{"username": user.Username}
+	if messageType == model.POST_ADD_TO_CHANNEL {
+		props["addedUsername"] = otherUsername
+	}
+
+	if messageType == model.POST_REMOVE_FROM_CHANNEL {
+		props["removedUsername"] = user.Username
+		delete(props, "username")
+	}
+
 	post := &model.Post{
 		ChannelId: channel.Id,
-		Message:   fmt.Sprintf(utils.T("api.channel.join_channel.post_and_forget"), user.Username),
-		Type:      model.POST_JOIN_CHANNEL,
+		Message:   message,
+		Type:      messageType,
 		UserId:    user.Id,
-		Props: model.StringInterface{
-			"username": user.Username,
-		},
+		Props:     props,
 	}
 
 	if _, err := CreatePost(post, channel.TeamId, false); err != nil {
-		return model.NewLocAppError("postJoinChannelMessage", "api.channel.post_user_add_remove_message_and_forget.error", nil, err.Error())
+		return model.NewLocAppError("createUserActivitySystemMessage", "api.channel.create_user_activity_post.error", nil, err.Error())
+	}
+
+	return nil
+}
+
+func updateUserActivitySystemMessage(post *model.Post, username, otherUsername, messageType, messageToAdd string) *model.AppError {
+	post.Message += " " + messageToAdd
+	props := model.StringMap{"type": messageType, "username": username}
+	if messageType == model.POST_ADD_TO_CHANNEL {
+		props["addedUsername"] = otherUsername
+	}
+
+	if messageType == model.POST_REMOVE_FROM_CHANNEL {
+		props["removedUsername"] = username
+		delete(props, "username")
+	}
+
+	if val, ok := post.Props["messages"]; ok {
+		post.Props["messages"] = append(val.([]interface{}), props)
+	} else {
+		oldProps := make(model.StringInterface)
+		for key, value := range post.Props {
+			oldProps[key] = value
+		}
+		oldProps["type"] = post.Type
+		post.Props["messages"] = []interface{}{oldProps, props}
+	}
+
+	if _, err := UpdatePost(post, false); err != nil {
+		return model.NewLocAppError("updateUserActivitySystemMessage", "api.channel.update_user_activity_post.error", nil, err.Error())
+	}
+
+	return nil
+}
+
+func postJoinChannelMessage(user *model.User, channel *model.Channel) *model.AppError {
+	message := fmt.Sprintf(utils.T("api.channel.join_channel.post_and_forget"), user.Username)
+
+	if post, err := GetLastPostForChannel(channel.Id); err != nil {
+		return err
+	} else if post.IsUserActivitySystemMessage() {
+		if err := updateUserActivitySystemMessage(post, user.Username, "", model.POST_JOIN_CHANNEL, message); err != nil {
+			return err
+		}
+	} else {
+		if err := createUserActivitySystemMessage(channel, user, "", model.POST_JOIN_CHANNEL, message); err != nil {
+			return err
+		}
 	}
 
 	return nil
@@ -954,55 +1010,64 @@ func LeaveChannel(channelId string, userId string) *model.AppError {
 }
 
 func postLeaveChannelMessage(user *model.User, channel *model.Channel) *model.AppError {
-	post := &model.Post{
-		ChannelId: channel.Id,
-		Message:   fmt.Sprintf(utils.T("api.channel.leave.left"), user.Username),
-		Type:      model.POST_LEAVE_CHANNEL,
-		UserId:    user.Id,
-		Props: model.StringInterface{
-			"username": user.Username,
-		},
-	}
+	message := fmt.Sprintf(utils.T("api.channel.leave.left"), user.Username)
 
-	if _, err := CreatePost(post, channel.TeamId, false); err != nil {
-		return model.NewLocAppError("postLeaveChannelMessage", "api.channel.post_user_add_remove_message_and_forget.error", nil, err.Error())
+	if post, err := GetLastPostForChannel(channel.Id); err != nil {
+		return err
+	} else if post.IsUserActivitySystemMessage() {
+		if err := updateUserActivitySystemMessage(post, user.Username, "", model.POST_LEAVE_CHANNEL, message); err != nil {
+			return err
+		}
+	} else {
+		if err := createUserActivitySystemMessage(channel, user, "", model.POST_LEAVE_CHANNEL, message); err != nil {
+			return err
+		}
 	}
 
 	return nil
 }
 
 func PostAddToChannelMessage(user *model.User, addedUser *model.User, channel *model.Channel) *model.AppError {
-	post := &model.Post{
-		ChannelId: channel.Id,
-		Message:   fmt.Sprintf(utils.T("api.channel.add_member.added"), addedUser.Username, user.Username),
-		Type:      model.POST_ADD_TO_CHANNEL,
-		UserId:    user.Id,
-		Props: model.StringInterface{
-			"username":      user.Username,
-			"addedUsername": addedUser.Username,
-		},
-	}
+	message := fmt.Sprintf(utils.T("api.channel.add_member.added"), user.Username, addedUser.Username)
 
-	if _, err := CreatePost(post, channel.TeamId, false); err != nil {
-		return model.NewLocAppError("postAddToChannelMessage", "api.channel.post_user_add_remove_message_and_forget.error", nil, err.Error())
+	if post, err := GetLastPostForChannel(channel.Id); err != nil {
+		return err
+	} else if post.IsUserActivitySystemMessage() {
+		if err := updateUserActivitySystemMessage(post, user.Username, addedUser.Username, model.POST_ADD_TO_CHANNEL, message); err != nil {
+			return err
+		}
+
+		SendNotificationsForSystemMessageAddRemove(user, addedUser, channel, post)
+	} else {
+		if err := createUserActivitySystemMessage(channel, user, addedUser.Username, model.POST_ADD_TO_CHANNEL, message); err != nil {
+			return err
+		}
 	}
 
 	return nil
 }
 
 func PostRemoveFromChannelMessage(removerUserId string, removedUser *model.User, channel *model.Channel) *model.AppError {
-	post := &model.Post{
-		ChannelId: channel.Id,
-		Message:   fmt.Sprintf(utils.T("api.channel.remove_member.removed"), removedUser.Username),
-		Type:      model.POST_REMOVE_FROM_CHANNEL,
-		UserId:    removerUserId,
-		Props: model.StringInterface{
-			"removedUsername": removedUser.Username,
-		},
+	message := fmt.Sprintf(utils.T("api.channel.remove_member.removed"), removedUser.Username)
+
+	removerUser, err := GetUser(removerUserId)
+	if err != nil {
+		fmt.Printf("err: %+v\n", err)
+		return err
 	}
 
-	if _, err := CreatePost(post, channel.TeamId, false); err != nil {
-		return model.NewLocAppError("postRemoveFromChannelMessage", "api.channel.post_user_add_remove_message_and_forget.error", nil, err.Error())
+	if post, err := GetLastPostForChannel(channel.Id); err != nil {
+		return err
+	} else if post.IsUserActivitySystemMessage() {
+		if err := updateUserActivitySystemMessage(post, removedUser.Username, removerUser.Username, model.POST_REMOVE_FROM_CHANNEL, message); err != nil {
+			return err
+		}
+
+		SendNotificationsForSystemMessageAddRemove(removerUser, removedUser, channel, post)
+	} else {
+		if err := createUserActivitySystemMessage(channel, removedUser, removerUser.Username, model.POST_ADD_TO_CHANNEL, message); err != nil {
+			return err
+		}
 	}
 
 	return nil
@@ -1046,20 +1111,28 @@ func RemoveUserFromChannel(userIdToRemove string, removerUserId string, channel
 		return err
 	}
 
-	var user *model.User
-	if user, err = GetUser(userIdToRemove); err != nil {
+	var userToRemove *model.User
+	if userToRemove, err = GetUser(userIdToRemove); err != nil {
 		return err
 	}
 
 	if userIdToRemove == removerUserId {
-		postLeaveChannelMessage(user, channel)
+		postLeaveChannelMessage(userToRemove, channel)
 	} else {
-		go PostRemoveFromChannelMessage(removerUserId, user, channel)
+		go PostRemoveFromChannelMessage(removerUserId, userToRemove, channel)
 	}
 
 	return nil
 }
 
+func GetLastPostForChannel(channelId string) (*model.Post, *model.AppError) {
+	result := <-Srv.Store.Post().GetLastPostForChannel(channelId)
+	if result.Err != nil {
+		return nil, result.Err
+	}
+	return result.Data.(*model.Post), nil
+}
+
 func GetNumberOfChannelsOnTeam(teamId string) (int, *model.AppError) {
 	// Get total number of channels on current team
 	if result := <-Srv.Store.Channel().GetTeamChannels(teamId); result.Err != nil {

app/channel_test.go

@@ -1,6 +1,11 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
 package app
 
 import (
+	"fmt"
+	"reflect"
 	"testing"
 
 	"github.com/mattermost/platform/model"
@@ -64,3 +69,193 @@ func TestPermanentDeleteChannel(t *testing.T) {
 		t.Error("outgoing webhook wasn't deleted")
 	}
 }
+
+func PostUserActivitySystemMessage(t *testing.T, testFunc func(user *model.User, channel *model.Channel) *model.AppError, postType string, messageKey string) {
+	th := Setup().InitBasic()
+
+	// Test when last post was a leave/join post
+	user := &model.User{Id: model.NewId(), Email: "test@example.com", Username: "test"}
+
+	post := &model.Post{
+		ChannelId: th.BasicChannel.Id, UserId: user.Id, Type: postType, Message: "message",
+		Props: model.StringInterface{"username": user.Username},
+	}
+	post = (<-Srv.Store.Post().Save(post)).Data.(*model.Post)
+
+	testFunc(user, th.BasicChannel)
+	post = (<-Srv.Store.Post().GetSingle(post.Id)).Data.(*model.Post)
+	if post.Message != "message "+fmt.Sprintf(utils.T(messageKey), user.Username) {
+		t.Fatal("Leave/join a channel message wasn't appended to last leave/join post")
+	}
+
+	if !reflect.DeepEqual(
+		post.Props["messages"].([]interface{}),
+		[]interface{}{
+			map[string]interface{}{"type": postType, "username": user.Username},
+			map[string]interface{}{"type": postType, "username": user.Username},
+		},
+	) {
+		t.Fatal("Invalid leave/join a channel props")
+	}
+
+	// Test when last post was not a leave/join post
+	post.Id = ""
+	post.Message = "message1"
+	post.Type = model.POST_DEFAULT
+	post.Props = nil
+	post = (<-Srv.Store.Post().Save(post)).Data.(*model.Post)
+
+	testFunc(user, th.BasicChannel)
+	post = (<-Srv.Store.Post().GetSingle(post.Id)).Data.(*model.Post)
+	if post.Message == "message1 "+fmt.Sprintf(utils.T(messageKey), user.Username) {
+		t.Fatal("Leave/join a channel message was appended to last non leave/join post")
+	}
+
+	if _, ok := post.Props["messages"]; ok {
+		t.Fatal("Invalid leave/join a channel props. \"message\" shouldn't be present")
+	}
+}
+
+func TestPostJoinChannelMessage(t *testing.T) {
+	PostUserActivitySystemMessage(t, postJoinChannelMessage, model.POST_JOIN_CHANNEL, "api.channel.join_channel.post_and_forget")
+}
+
+func TestPostLeaveChannelMessage(t *testing.T) {
+	PostUserActivitySystemMessage(t, postLeaveChannelMessage, model.POST_LEAVE_CHANNEL, "api.channel.leave.left")
+}
+
+func TestPostAddToChannelMessage(t *testing.T) {
+	th := Setup().InitBasic()
+
+	// Test when last post was a user activity system message post
+	user := &model.User{Id: model.NewId(), Email: "test@example.com", Username: "test"}
+	addedUser := &model.User{Id: model.NewId(), Email: "test1@example.com", Username: "test1"}
+
+	post := &model.Post{
+		ChannelId: th.BasicChannel.Id, UserId: user.Id, Type: model.POST_ADD_TO_CHANNEL, Message: "message",
+		Props: model.StringInterface{"username": user.Username, "addedUsername": addedUser.Username},
+	}
+	post = (<-Srv.Store.Post().Save(post)).Data.(*model.Post)
+
+	PostAddToChannelMessage(user, addedUser, th.BasicChannel)
+	post = (<-Srv.Store.Post().GetSingle(post.Id)).Data.(*model.Post)
+	if post.Message != "message "+fmt.Sprintf(utils.T("api.channel.add_member.added"), user.Username, addedUser.Username) {
+		t.Fatal("Add message wasn't appended to last user activity system message post")
+	}
+
+	if !reflect.DeepEqual(
+		post.Props["messages"].([]interface{}),
+		[]interface{}{
+			map[string]interface{}{"type": model.POST_ADD_TO_CHANNEL, "username": user.Username, "addedUsername": addedUser.Username},
+			map[string]interface{}{"type": model.POST_ADD_TO_CHANNEL, "username": user.Username, "addedUsername": addedUser.Username},
+		},
+	) {
+		t.Fatal("Invalid added to channel props")
+	}
+
+	// Test when last post was not a user activity system message post
+	post.Id = ""
+	post.Message = "message1"
+	post.Type = model.POST_DEFAULT
+	post.Props = nil
+	post = (<-Srv.Store.Post().Save(post)).Data.(*model.Post)
+
+	PostAddToChannelMessage(user, addedUser, th.BasicChannel)
+	post = (<-Srv.Store.Post().GetSingle(post.Id)).Data.(*model.Post)
+	if post.Message == "message1\n"+fmt.Sprintf(utils.T("api.channel.add_member.added"), addedUser.Username, user.Username) {
+		t.Fatal("Added to channel message was appended to last non user activity system message post")
+	}
+
+	if _, ok := post.Props["messages"]; ok {
+		t.Fatal("Invalid added to channel props. \"message\" shouldn't be present")
+	}
+}
+
+func TestPostRemoveFromChannelMessage(t *testing.T) {
+	th := Setup().InitBasic()
+	user := th.BasicUser
+
+	// // Test when last post was a user activity system message post
+	removedUser := &model.User{Id: model.NewId(), Email: "test1@example.com", Username: "test1"}
+
+	post := &model.Post{
+		ChannelId: th.BasicChannel.Id, UserId: user.Id, Type: model.POST_REMOVE_FROM_CHANNEL, Message: "message",
+		Props: model.StringInterface{"removedUsername": removedUser.Username},
+	}
+	post = (<-Srv.Store.Post().Save(post)).Data.(*model.Post)
+
+	PostRemoveFromChannelMessage(user.Id, removedUser, th.BasicChannel)
+	post = (<-Srv.Store.Post().GetSingle(post.Id)).Data.(*model.Post)
+	if post.Message != "message "+fmt.Sprintf(utils.T("api.channel.remove_member.removed"), removedUser.Username) {
+		t.Fatal("Post removed from a channel message wasn't appended to last user activity system message post")
+	}
+
+	if !reflect.DeepEqual(
+		post.Props["messages"].([]interface{}),
+		[]interface{}{
+			map[string]interface{}{"type": model.POST_REMOVE_FROM_CHANNEL, "removedUsername": removedUser.Username},
+			map[string]interface{}{"type": model.POST_REMOVE_FROM_CHANNEL, "removedUsername": removedUser.Username},
+		},
+	) {
+		t.Fatal("Invalid removed from a channel props")
+	}
+
+	// Test when last post was not a user activity system message post
+	post.Id = ""
+	post.Message = "message1"
+	post.Type = model.POST_DEFAULT
+	post.Props = nil
+	post = (<-Srv.Store.Post().Save(post)).Data.(*model.Post)
+
+	PostRemoveFromChannelMessage(user.Id, removedUser, th.BasicChannel)
+	post = (<-Srv.Store.Post().GetSingle(post.Id)).Data.(*model.Post)
+	if post.Message == "message1 "+fmt.Sprintf(utils.T("api.channel.remove_member.removed"), removedUser.Username) {
+		t.Fatal("Post removed from a channel message was appended to last non user activity system message post")
+	}
+
+	if _, ok := post.Props["messages"]; ok {
+		t.Fatal("Invalid removed from a channel props. \"message\" shouldn't be present")
+	}
+}
+
+func TestGetLastPostForChannel(t *testing.T) {
+	th := Setup().InitBasic()
+	user := th.BasicUser
+
+	post1 := &model.Post{
+		ChannelId: th.BasicChannel.Id,
+		UserId:    user.Id,
+		Message:   "message",
+	}
+	post1 = (<-Srv.Store.Post().Save(post1)).Data.(*model.Post)
+
+	rpost1, err := GetLastPostForChannel(th.BasicChannel.Id)
+	if err != nil {
+		t.Fatal("Last post should have been returned")
+	}
+
+	if post1.Message != rpost1.Message {
+		t.Fatal("Should match post message")
+	}
+
+	post2 := &model.Post{
+		ChannelId: th.BasicChannel.Id,
+		UserId:    user.Id,
+		Message:   "message",
+	}
+	post2 = (<-Srv.Store.Post().Save(post2)).Data.(*model.Post)
+
+	rpost2, err := GetLastPostForChannel(th.BasicChannel.Id)
+	if err != nil {
+		t.Fatal("Last post should have been returned")
+	}
+
+	if post2.Message != rpost2.Message {
+		t.Fatal("Should match post message")
+	}
+
+	_, err = GetLastPostForChannel(model.NewId())
+	if err != nil {
+		t.Fatal("Should not return err")
+	}
+}

app/notification.go

@@ -306,6 +306,91 @@ func SendNotifications(post *model.Post, team *model.Team, channel *model.Channe
 	return mentionedUsersList, nil
 }
 
+func SendNotificationsForSystemMessageAddRemove(user *model.User, otherUser *model.User, channel *model.Channel, post *model.Post) *model.AppError {
+	otherUserChannelMember, _ := GetChannelMember(channel.Id, otherUser.Id)
+	team, err := GetTeam(channel.TeamId)
+	if err != nil {
+		return err
+	}
+
+	err = (<-Srv.Store.Channel().IncrementMentionCount(channel.Id, otherUser.Id)).Err
+	if err != nil {
+		return err
+	}
+
+	if utils.Cfg.EmailSettings.SendEmailNotifications {
+		userAllowsEmails := otherUser.NotifyProps[model.EMAIL_NOTIFY_PROP] != "false"
+		if otherUserChannelMember != nil {
+			channelEmail, ok := otherUserChannelMember.NotifyProps[model.EMAIL_NOTIFY_PROP]
+			if ok && channelEmail != model.CHANNEL_NOTIFY_DEFAULT {
+				userAllowsEmails = channelEmail != "false"
+			}
+		}
+
+		var status *model.Status
+		var err *model.AppError
+		if status, err = GetStatus(otherUser.Id); err != nil {
+			status = &model.Status{
+				UserId:         otherUser.Id,
+				Status:         model.STATUS_OFFLINE,
+				Manual:         false,
+				LastActivityAt: 0,
+				ActiveChannel:  "",
+			}
+		}
+
+		senderName := utils.T("system.message.name")
+		if userAllowsEmails && status.Status != model.STATUS_ONLINE && otherUser.DeleteAt == 0 {
+			if err = sendNotificationEmail(post, otherUser, channel, team, senderName, user); err != nil {
+				return err
+			}
+		}
+	}
+
+	if otherUserChannelMember != nil {
+		sendPushNotifications := false
+		if *utils.Cfg.EmailSettings.SendPushNotifications {
+			pushServer := *utils.Cfg.EmailSettings.PushNotificationServer
+			if pushServer == model.MHPNS && (!utils.IsLicensed || !*utils.License.Features.MHPNS) {
+				l4g.Warn(utils.T("api.post.send_notifications_and_forget.push_notification.mhpnsWarn"))
+				sendPushNotifications = false
+			} else {
+				sendPushNotifications = true
+			}
+		}
+
+		channelName := channel.DisplayName
+		senderUsername := user.Username
+
+		if sendPushNotifications {
+			var status *model.Status
+			var err *model.AppError
+			if status, err = GetStatus(otherUser.Id); err != nil {
+				status = &model.Status{UserId: otherUser.Id, Status: model.STATUS_OFFLINE, Manual: false, LastActivityAt: 0, ActiveChannel: ""}
+			}
+
+			if ShouldSendPushNotification(otherUser, otherUserChannelMember.NotifyProps, true, status, post) {
+				if err = sendPushNotification(post, otherUser, channel, senderUsername, channelName, true); err != nil {
+					return err
+				}
+			}
+		}
+
+		message := model.NewWebSocketEvent(model.WEBSOCKET_EVENT_POSTED, "", post.ChannelId, "", nil)
+		message.Add("post", post.ToJson())
+		message.Add("channel_type", channel.Type)
+		message.Add("channel_display_name", channelName)
+		message.Add("channel_name", channel.Name)
+		message.Add("sender_name", senderUsername)
+		message.Add("team_id", channel.TeamId)
+		message.Add("mentions", otherUser.Username)
+
+		Publish(message)
+	}
+
+	return nil
+}
+
 func sendNotificationEmail(post *model.Post, user *model.User, channel *model.Channel, team *model.Team, senderName string, sender *model.User) *model.AppError {
 	if channel.IsGroupOrDirect() {
 		if result := <-Srv.Store.Team().GetTeamsByUserId(user.Id); result.Err != nil {

app/post.go

@@ -250,8 +250,8 @@ func UpdatePost(post *model.Post, safeUpdate bool) (*model.Post, *model.AppError
 			return nil, err
 		}
 
-		if oldPost.IsSystemMessage() {
-			err := model.NewAppError("UpdatePost", "api.post.update_post.system_message.app_error", nil, "id="+post.Id, http.StatusBadRequest)
+		if oldPost.IsSystemMessage() && !oldPost.IsUserActivitySystemMessage() {
+			err := model.NewAppError("updatePost", "api.post.update_post.system_message.app_error", nil, "id="+post.Id, http.StatusBadRequest)
 			return nil, err
 		}
 

i18n/en.json

@@ -153,7 +153,7 @@
   },
   {
     "id": "api.channel.add_member.added",
-    "translation": "%v added to the channel by %v"
+    "translation": "%v added %v to the channel."
   },
   {
     "id": "api.channel.add_member.find_channel.app_error",
@@ -297,7 +297,7 @@
   },
   {
     "id": "api.channel.join_channel.post_and_forget",
-    "translation": "%v has joined the channel."
+    "translation": "%v joined the channel."
   },
   {
     "id": "api.channel.leave.default.app_error",
@@ -313,7 +313,7 @@
   },
   {
     "id": "api.channel.leave.left",
-    "translation": "%v has left the channel."
+    "translation": "%v left the channel."
   },
   {
     "id": "api.channel.post_update_channel_displayname_message_and_forget.create_post.error",
@@ -347,6 +347,14 @@
     "id": "api.channel.post_update_channel_header_message_and_forget.updated_to",
     "translation": "%s updated the channel header to: %s"
   },
+  {
+    "id": "api.channel.create_user_activity_post.error",
+    "translation": "Failed to create user activity system message like add, remove, join or leave"
+  },
+  {
+    "id": "api.channel.update_user_activity_post.error",
+    "translation": "Failed to update user activity system message like add, remove, join or leave"
+  },
   {
     "id": "api.channel.post_user_add_remove_message_and_forget.error",
     "translation": "Failed to post join/leave message"

model/post.go

@@ -205,6 +205,15 @@ func (o *Post) IsSystemMessage() bool {
 	return len(o.Type) >= len(POST_SYSTEM_MESSAGE_PREFIX) && o.Type[:len(POST_SYSTEM_MESSAGE_PREFIX)] == POST_SYSTEM_MESSAGE_PREFIX
 }
 
+func (o *Post) IsUserActivitySystemMessage() bool {
+	return o.Type == POST_JOIN_LEAVE ||
+		o.Type == POST_JOIN_CHANNEL ||
+		o.Type == POST_LEAVE_CHANNEL ||
+		o.Type == POST_ADD_REMOVE ||
+		o.Type == POST_ADD_TO_CHANNEL ||
+		o.Type == POST_REMOVE_FROM_CHANNEL
+}
+
 func (p *Post) Patch(patch *PostPatch) {
 	if patch.IsPinned != nil {
 		p.IsPinned = *patch.IsPinned

model/post_test.go

@@ -113,3 +113,48 @@ func TestPostIsSystemMessage(t *testing.T) {
 		t.Fatalf("TestPostIsSystemMessage failed, expected post2.IsSystemMessage() to be true")
 	}
 }
+
+func TestPostIsUserActivitySystemMessage(t *testing.T) {
+	post1 := Post{Message: "test_1"}
+	post1.PreSave()
+
+	if post1.IsUserActivitySystemMessage() {
+		t.Fatalf("TestPostIsUserActivitySystemMessage failed, expected post1.IsSystemMessage() to be false")
+	}
+
+	post2 := Post{Message: "test_2", Type: POST_JOIN_LEAVE}
+	post2.PreSave()
+	if !post2.IsUserActivitySystemMessage() {
+		t.Fatalf("TestPostIsUserActivitySystemMessage failed, expected post2.IsSystemMessage() to be true")
+	}
+
+	post3 := Post{Message: "test_3", Type: POST_JOIN_CHANNEL}
+	post3.PreSave()
+	if !post3.IsUserActivitySystemMessage() {
+		t.Fatalf("TestPostIsUserActivitySystemMessage failed, expected post3.IsSystemMessage() to be true")
+	}
+
+	post4 := Post{Message: "test_4", Type: POST_LEAVE_CHANNEL}
+	post4.PreSave()
+	if !post4.IsUserActivitySystemMessage() {
+		t.Fatalf("TestPostIsUserActivitySystemMessage failed, expected post4.IsSystemMessage() to be true")
+	}
+
+	post5 := Post{Message: "test_5", Type: POST_ADD_REMOVE}
+	post5.PreSave()
+	if !post5.IsUserActivitySystemMessage() {
+		t.Fatalf("TestPostIsUserActivitySystemMessage failed, expected post5.IsSystemMessage() to be true")
+	}
+
+	post6 := Post{Message: "test_6", Type: POST_ADD_TO_CHANNEL}
+	post6.PreSave()
+	if !post6.IsUserActivitySystemMessage() {
+		t.Fatalf("TestPostIsUserActivitySystemMessage failed, expected post6.IsSystemMessage() to be true")
+	}
+
+	post7 := Post{Message: "test_7", Type: POST_REMOVE_FROM_CHANNEL}
+	post7.PreSave()
+	if !post7.IsUserActivitySystemMessage() {
+		t.Fatalf("TestPostIsUserActivitySystemMessage failed, expected post7.IsSystemMessage() to be true")
+	}
+}

store/sql_post_store.go

@@ -97,8 +97,7 @@ func (s SqlPostStore) Save(post *model.Post) StoreChannel {
 		} else {
 			time := post.UpdateAt
 
-			if post.Type != model.POST_JOIN_LEAVE && post.Type != model.POST_JOIN_CHANNEL && post.Type != model.POST_LEAVE_CHANNEL &&
-				post.Type != model.POST_ADD_REMOVE && post.Type != model.POST_ADD_TO_CHANNEL && post.Type != model.POST_REMOVE_FROM_CHANNEL {
+			if !post.IsUserActivitySystemMessage() {
 				s.GetMaster().Exec("UPDATE Channels SET LastPostAt = :LastPostAt, TotalMsgCount = TotalMsgCount + 1 WHERE Id = :ChannelId", map[string]interface{}{"LastPostAt": time, "ChannelId": post.ChannelId})
 			} else {
 				// don't update TotalMsgCount for unimportant messages so that the channel isn't marked as unread
@@ -1355,3 +1354,29 @@ func (s SqlPostStore) GetPostsBatchForIndexing(startTime int64, limit int) Store
 
 	return storeChannel
 }
+
+func (s SqlPostStore) GetLastPostForChannel(channelId string) StoreChannel {
+	storeChannel := make(StoreChannel, 1)
+
+	go func() {
+		result := StoreResult{}
+
+		var post model.Post
+		query := `
+			SELECT * FROM Posts 
+			WHERE ChannelId = :channelId AND DeleteAt = 0
+			ORDER BY CreateAt DESC
+			LIMIT 1
+		`
+
+		if err := s.GetReplica().SelectOne(&post, query, map[string]interface{}{"channelId": channelId}); err != nil {
+			l4g.Error(err)
+		}
+
+		result.Data = &post
+		storeChannel <- result
+		close(storeChannel)
+	}()
+
+	return storeChannel
+}

store/sql_post_store_test.go

@@ -1661,3 +1661,37 @@ func TestPostStoreGetPostsBatchForIndexing(t *testing.T) {
 		}
 	}
 }
+
+func TestGetLastPostForChannel(t *testing.T) {
+	Setup()
+
+	o1 := &model.Post{}
+	o1.ChannelId = model.NewId()
+	o1.UserId = model.NewId()
+	o1.Message = ""
+	o1.Type = model.POST_JOIN_CHANNEL
+
+	o1 = (<-store.Post().Save(o1)).Data.(*model.Post)
+
+	if r1 := <-store.Post().GetLastPostForChannel(o1.ChannelId); r1.Err != nil {
+		t.Fatal(r1.Err)
+	} else {
+		if r1.Data.(*model.Post).Id != o1.Id {
+			t.Fatal("invalid returned post")
+		}
+	}
+
+	o2 := &model.Post{}
+	o2.ChannelId = o1.ChannelId
+	o2.UserId = model.NewId()
+	o2.Message = ""
+
+	o2 = (<-store.Post().Save(o2)).Data.(*model.Post)
+	if r2 := <-store.Post().GetLastPostForChannel(o2.ChannelId); r2.Err != nil {
+		t.Fatal(r2.Err)
+	} else {
+		if r2.Data.(*model.Post).Id != o2.Id {
+			t.Fatal("invalid returned post")
+		}
+	}
+}

store/store.go

@@ -170,6 +170,7 @@ type PostStore interface {
 	Overwrite(post *model.Post) StoreChannel
 	GetPostsByIds(postIds []string) StoreChannel
 	GetPostsBatchForIndexing(startTime int64, limit int) StoreChannel
+	GetLastPostForChannel(channelId string) StoreChannel
 }
 
 type UserStore interface {

webapp/components/post_view/post_message_view/system_message_helpers.jsx

@@ -7,6 +7,13 @@ import {FormattedMessage} from 'react-intl';
 import {PostTypes} from 'utils/constants.jsx';
 import {formatText} from 'utils/text_formatting.jsx';
 
+const joinLeaveMessageGetters = {
+    [PostTypes.JOIN_CHANNEL]: getJoinChannelMessage,
+    [PostTypes.LEAVE_CHANNEL]: getLeaveChannelMessage,
+    [PostTypes.ADD_TO_CHANNEL]: getAddToChannelMessage,
+    [PostTypes.REMOVE_FROM_CHANNEL]: getRemoveFromChannelMessage
+};
+
 function renderUsername(value, options) {
     return renderFormattedText(value, {...options, markdown: false});
 }
@@ -15,38 +22,60 @@ function renderFormattedText(value, options) {
     return <span dangerouslySetInnerHTML={{__html: formatText(value, options)}}/>;
 }
 
+function renderJoinLeaveMessage(post, options, messageFunction) {
+    if (post.props.messages) {
+        return (
+            <div>
+                {post.props.messages.map((message, key) => <span key={key}> {joinLeaveMessageGetters[message.type](message, options)}</span>)}
+            </div>
+        );
+    }
+    return messageFunction(post.props, options);
+}
+
 function renderJoinChannelMessage(post, options) {
-    const username = renderUsername(post.props.username, options);
+    return renderJoinLeaveMessage(post, options, getJoinChannelMessage);
+}
+
+function getJoinChannelMessage(messageProps, options) {
+    const username = renderUsername(messageProps.username, options);
 
     return (
         <FormattedMessage
             id='api.channel.join_channel.post_and_forget'
-            defaultMessage='{username} has joined the channel.'
+            defaultMessage='{username} joined the channel.'
             values={{username}}
         />
     );
 }
 
 function renderLeaveChannelMessage(post, options) {
-    const username = renderUsername(post.props.username, options);
+    return renderJoinLeaveMessage(post, options, getLeaveChannelMessage);
+}
+
+function getLeaveChannelMessage(messageProps, options) {
+    const username = renderUsername(messageProps.username, options);
 
     return (
         <FormattedMessage
             id='api.channel.leave.left'
-            defaultMessage='{username} has left the channel.'
+            defaultMessage='{username} left the channel.'
             values={{username}}
         />
     );
 }
 
 function renderAddToChannelMessage(post, options) {
-    const username = renderUsername(post.props.username, options);
-    const addedUsername = renderUsername(post.props.addedUsername, options);
+    return renderJoinLeaveMessage(post, options, getAddToChannelMessage);
+}
 
+function getAddToChannelMessage(messageProps, options) {
+    const username = renderUsername(messageProps.username, options);
+    const addedUsername = renderUsername(messageProps.addedUsername, options);
     return (
         <FormattedMessage
             id='api.channel.add_member.added'
-            defaultMessage='{addedUsername} added to the channel by {username}'
+            defaultMessage='{username} added {addedUsername} to the channel.'
             values={{
                 username,
                 addedUsername
@@ -56,12 +85,16 @@ function renderAddToChannelMessage(post, options) {
 }
 
 function renderRemoveFromChannelMessage(post, options) {
-    const removedUsername = renderUsername(post.props.removedUsername, options);
+    return renderJoinLeaveMessage(post, options, getRemoveFromChannelMessage);
+}
+
+function getRemoveFromChannelMessage(messageProps, options) {
+    const removedUsername = renderUsername(messageProps.removedUsername, options);
 
     return (
         <FormattedMessage
             id='api.channel.remove_member.removed'
-            defaultMessage='{removedUsername} was removed from the channel'
+            defaultMessage='{removedUsername} was removed from the channel.'
             values={{
                 removedUsername
             }}

webapp/i18n/en.json

@@ -1015,15 +1015,15 @@
   "analytics.team.title": "Team Statistics for {team}",
   "analytics.team.totalPosts": "Total Posts",
   "analytics.team.totalUsers": "Total Users",
-  "api.channel.add_member.added": "{addedUsername} added to the channel by {username}",
+  "api.channel.add_member.added": " {username} added {addedUsername} to the channel.",
   "api.channel.delete_channel.archived": "{username} has archived the channel.",
-  "api.channel.join_channel.post_and_forget": "{username} has joined the channel.",
-  "api.channel.leave.left": "{username} has left the channel.",
+  "api.channel.join_channel.post_and_forget": "{username} joined the channel.",
+  "api.channel.leave.left": "{username} left the channel.",
   "api.channel.post_update_channel_displayname_message_and_forget.updated_from": "{username} updated the channel display name from: {old} to: {new}",
   "api.channel.post_update_channel_header_message_and_forget.removed": "{username} removed the channel header (was: {old})",
   "api.channel.post_update_channel_header_message_and_forget.updated_from": "{username} updated the channel header from: {old} to: {new}",
   "api.channel.post_update_channel_header_message_and_forget.updated_to": "{username} updated the channel header to: {new}",
-  "api.channel.remove_member.removed": "{removedUsername} was removed from the channel",
+  "api.channel.remove_member.removed": "{removedUsername} was removed from the channel.",
   "app.channel.post_update_channel_purpose_message.removed": "{username} removed the channel purpose (was: {old})",
   "app.channel.post_update_channel_purpose_message.updated_from": "{username} updated the channel purpose from: {old} to: {new}",
   "app.channel.post_update_channel_purpose_message.updated_to": "{username} updated the channel purpose to: {new}",