MM-52804 - Implement SendPushNotification plugin api method (#24273)

* add SendPushNotification plugin api method

* lint; add testing.Short bc of the sleep

* add interface and generated layers

* add fields to PluginPushNotification; generate mocks

* SendPushNotification -> SendPluginPushNotification; improved comments

* more comments; fix test

* send api.ctx

server/channels/app/notification_push.go

@@ -143,9 +143,12 @@ func (a *App) sendPushNotification(notification *PostNotification, user *model.U
 	cancelled := false
 	a.ch.RunMultiHook(func(hooks plugin.Hooks) bool {
 		cancelled = hooks.NotificationWillBePushed(&model.PluginPushNotification{
-			Post:    notification.Post.ForPlugin(),
-			Channel: notification.Channel,
-			UserID:  user.Id,
+			Post:               notification.Post.ForPlugin(),
+			Channel:            notification.Channel,
+			UserID:             user.Id,
+			ExplicitMention:    explicitMention,
+			ChannelWideMention: channelWideMention,
+			ReplyToThreadType:  replyToThreadType,
 		})
 		if cancelled {
 			mlog.Info("Notification cancelled by plugin")

server/channels/app/plugin_api.go

@@ -1266,3 +1266,31 @@ func (api *PluginAPI) GetUploadSession(uploadID string) (*model.UploadSession, e
 	}
 	return fi, nil
 }
+
+func (api *PluginAPI) SendPluginPushNotification(notification *model.PluginPushNotification) error {
+	var profiles map[string]*model.User
+	var err error
+	if notification.Channel.Type == model.ChannelTypeGroup {
+		if profiles, err = api.app.Srv().Store().User().GetAllProfilesInChannel(api.ctx.Context(), notification.Channel.Id, true); err != nil {
+			return err
+		}
+	}
+
+	sender, appErr := api.app.GetUser(notification.Post.UserId)
+	if appErr != nil {
+		return appErr
+	}
+	user, appErr := api.app.GetUser(notification.UserID)
+	if appErr != nil {
+		return appErr
+	}
+
+	postNotification := &PostNotification{
+		Post:       notification.Post,
+		Channel:    notification.Channel,
+		ProfileMap: profiles,
+		Sender:     sender,
+	}
+	api.app.sendPushNotification(postNotification, user, notification.ExplicitMention, notification.ChannelWideMention, notification.ReplyToThreadType)
+	return nil
+}

server/channels/app/plugin_api_test.go

@@ -19,6 +19,7 @@ import (
 	"path"
 	"path/filepath"
 	"strings"
+	"sync"
 	"testing"
 	"time"
 
@@ -2204,3 +2205,91 @@ func TestConfigurationWillBeSavedHook(t *testing.T) {
 		}, newCfg.PluginSettings.Plugins["custom_plugin"])
 	})
 }
+
+func TestSendPushNotification(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping TestSendPushNotification test in short mode")
+	}
+
+	th := Setup(t).InitBasic()
+	defer th.TearDown()
+	api := th.SetupPluginAPI()
+
+	// Create 3 users, each having 2 sessions.
+	type userSession struct {
+		user    *model.User
+		session *model.Session
+	}
+	var userSessions []userSession
+	for i := 0; i < 3; i++ {
+		u := th.CreateUser()
+		sess, err := th.App.CreateSession(&model.Session{
+			UserId:    u.Id,
+			DeviceId:  "deviceID" + u.Id,
+			ExpiresAt: model.GetMillis() + 100000,
+		})
+		require.Nil(t, err)
+		// We don't need to track the 2nd session.
+		_, err = th.App.CreateSession(&model.Session{
+			UserId:    u.Id,
+			DeviceId:  "deviceID" + u.Id,
+			ExpiresAt: model.GetMillis() + 100000,
+		})
+		require.Nil(t, err)
+		_, err = th.App.AddTeamMember(th.Context, th.BasicTeam.Id, u.Id)
+		require.Nil(t, err)
+		th.AddUserToChannel(u, th.BasicChannel)
+		userSessions = append(userSessions, userSession{
+			user:    u,
+			session: sess,
+		})
+	}
+
+	handler := &testPushNotificationHandler{
+		t:        t,
+		behavior: "simple",
+	}
+	pushServer := httptest.NewServer(
+		http.HandlerFunc(handler.handleReq),
+	)
+	defer pushServer.Close()
+
+	th.App.UpdateConfig(func(cfg *model.Config) {
+		*cfg.EmailSettings.PushNotificationContents = model.FullNotification
+		*cfg.EmailSettings.PushNotificationServer = pushServer.URL
+	})
+
+	var wg sync.WaitGroup
+	for _, data := range userSessions {
+		wg.Add(1)
+		go func(user model.User) {
+			defer wg.Done()
+			post := th.CreatePost(th.BasicChannel)
+			post.Message = "started a conversation"
+			notification := &model.PluginPushNotification{
+				Post:    post,
+				Channel: th.BasicChannel,
+				UserID:  user.Id,
+			}
+			appErr := api.SendPluginPushNotification(notification)
+			require.NoError(t, appErr)
+		}(*data.user)
+	}
+	wg.Wait()
+
+	// Hack to let the worker goroutines complete.
+	time.Sleep(1 * time.Second)
+	// Server side verification.
+	var numMessages int
+	for _, n := range handler.notifications() {
+		switch n.Type {
+		case model.PushTypeMessage:
+			numMessages++
+			assert.Equal(t, th.BasicChannel.Id, n.ChannelId)
+			assert.Equal(t, fmt.Sprintf("@%s: started a conversation", th.BasicUser.GetDisplayName(model.ShowUsername)), n.Message)
+		default:
+			assert.Fail(t, "should not receive any other push notification types")
+		}
+	}
+	assert.Equal(t, 6, numMessages)
+}

server/public/model/plugin_push_notification.go

@@ -4,9 +4,18 @@
 package model
 
 // PluginPushNotification is sent to the plugin when a push notification is going to be sent (via the
-// NotificationWillBePushed hook).
+// NotificationWillBePushed hook), and is used as the source data for the plugin api SendPluginPushNotification method.
+//
+// Note: Please keep in mind that Mattermost push notifications always refer to a specific post. Therefore, when used
+// as source data for `SendPluginPushNotification`, Post and Channel must be valid in order to create a correct
+// model.PushNotification.
+// Note: Post and Channel are pointers so that plugins using the NotificationWillBePushed hook will not need to query the
+// database on every push notification.
 type PluginPushNotification struct {
-	Post    *Post
-	Channel *Channel
-	UserID  string
+	Post               *Post    // The post that will be used as the source of the push notification.
+	Channel            *Channel // The channel that the post appeared in.
+	UserID             string   // The receiver of the push notification.
+	ExplicitMention    bool     // Used to construct the generic "@sender mentioned you" msg when `cfg.EmailSettings.PushNotificationContents` is not set to `full`
+	ChannelWideMention bool     // Used to construct the generic "@sender notified the channel" msg when `cfg.EmailSettings.PushNotificationContents` is not set to `full`
+	ReplyToThreadType  string   // Used to construct the generic CRT msgs when `cfg.EmailSettings.PushNotificationContents` is not set to `full`; see `App.getPushNotificationMessage` for details.
 }

server/public/plugin/api.go

@@ -1180,6 +1180,15 @@ type API interface {
 	// @tag Upload
 	// Minimum server version: 7.6
 	GetUploadSession(uploadID string) (*model.UploadSession, error)
+
+	// SendPluginPushNotification will attempt to send a push notification to `notification.User`, using
+	// `notification.Post` as the source of the notification. The server will use the PluginPushNotification
+	// data to construct the final push notification according to the server's configuration and license. Refer
+	// to `App.BuildPushNotificationMessage` for the logic used to construct the push notification.
+	// Note: the NotificationWillBePushed hook will be run after SendPluginPushNotification is called.
+	//
+	// Minimum server version: 9.0
+	SendPluginPushNotification(notification *model.PluginPushNotification) error
 }
 
 var handshake = plugin.HandshakeConfig{

server/public/plugin/api_timer_layer_generated.go

@@ -1266,3 +1266,10 @@ func (api *apiTimerLayer) GetUploadSession(uploadID string) (*model.UploadSessio
 	api.recordTime(startTime, "GetUploadSession", _returnsB == nil)
 	return _returnsA, _returnsB
 }
+
+func (api *apiTimerLayer) SendPluginPushNotification(notification *model.PluginPushNotification) error {
+	startTime := timePkg.Now()
+	_returnsA := api.apiImpl.SendPluginPushNotification(notification)
+	api.recordTime(startTime, "SendPluginPushNotification", _returnsA == nil)
+	return _returnsA
+}

server/public/plugin/client_rpc_generated.go

@@ -5868,3 +5868,32 @@ func (s *apiRPCServer) GetUploadSession(args *Z_GetUploadSessionArgs, returns *Z
 	}
 	return nil
 }
+
+type Z_SendPluginPushNotificationArgs struct {
+	A *model.PluginPushNotification
+}
+
+type Z_SendPluginPushNotificationReturns struct {
+	A error
+}
+
+func (g *apiRPCClient) SendPluginPushNotification(notification *model.PluginPushNotification) error {
+	_args := &Z_SendPluginPushNotificationArgs{notification}
+	_returns := &Z_SendPluginPushNotificationReturns{}
+	if err := g.client.Call("Plugin.SendPluginPushNotification", _args, _returns); err != nil {
+		log.Printf("RPC call to SendPluginPushNotification API failed: %s", err.Error())
+	}
+	return _returns.A
+}
+
+func (s *apiRPCServer) SendPluginPushNotification(args *Z_SendPluginPushNotificationArgs, returns *Z_SendPluginPushNotificationReturns) error {
+	if hook, ok := s.impl.(interface {
+		SendPluginPushNotification(notification *model.PluginPushNotification) error
+	}); ok {
+		returns.A = hook.SendPluginPushNotification(args.A)
+		returns.A = encodableError(returns.A)
+	} else {
+		return encodableError(fmt.Errorf("API SendPluginPushNotification called but not implemented."))
+	}
+	return nil
+}

server/public/plugin/hooks.go

@@ -291,6 +291,9 @@ type Hooks interface {
 	//
 	// To cancel a push notification, return true.
 	//
+	// Note that this method will be called for push notification sent by plugins, including
+	// the plugin that created the push notification.
+	//
 	// Minimum server version: 9.0
 	NotificationWillBePushed(pushNotification *model.PluginPushNotification) (cancel bool)
 }

server/public/plugin/plugintest/api.go

@@ -3639,6 +3639,20 @@ func (_m *API) SendMail(to string, subject string, htmlBody string) *model.AppEr
 	return r0
 }
 
+// SendPluginPushNotification provides a mock function with given fields: notification
+func (_m *API) SendPluginPushNotification(notification *model.PluginPushNotification) error {
+	ret := _m.Called(notification)
+
+	var r0 error
+	if rf, ok := ret.Get(0).(func(*model.PluginPushNotification) error); ok {
+		r0 = rf(notification)
+	} else {
+		r0 = ret.Error(0)
+	}
+
+	return r0
+}
+
 // SetProfileImage provides a mock function with given fields: userID, data
 func (_m *API) SetProfileImage(userID string, data []byte) *model.AppError {
 	ret := _m.Called(userID, data)