refactor(realtime): extract user event "online users" to SocketClient

1. extract user event "online users" to SocketClient
2. add test case for that

Signed-off-by: BoHong Li <a60814billy@gmail.com>

lib/realtime.js

@@ -773,6 +773,21 @@ class SocketClient {
     this.socket.on('cursor blur', this.cursorBlurEventHandlder.bind(this))
     // check version
     this.socket.on('version', this.checkVersionEventHandler.bind(this))
+    // received sync of online users request
+    this.socket.on('online users', this.onlineUsersEventHandler.bind(this))
+  }
+
+  onlineUsersEventHandler () {
+    if (!this.isNoteAndUserExists()) return
+
+    const currentNote = this.getCurrentNote()
+
+    const currentNoteOnlineUserList = Object.keys(currentNote.users)
+      .map(key => buildUserOutData(currentNote.users[key]))
+
+    this.socket.emit('online users', {
+      users: currentNoteOnlineUserList
+    })
   }
 
   isNoteAndUserExists () {
@@ -785,6 +800,10 @@ class SocketClient {
     return getUserFromUserPool(this.socket.id)
   }
 
+  getCurrentNote () {
+    return getNoteFromNotePool(this.socket.noteId)
+  }
+
   getNoteChannel () {
     return this.socket.broadcast.to(this.socket.noteId)
   }
@@ -990,23 +1009,6 @@ function connection (socket) {
     updateUserData(socket, user)
     emitOnlineUsers(socket)
   })
-
-  // received sync of online users request
-  socket.on('online users', function () {
-    var noteId = socket.noteId
-    if (!noteId || !notes[noteId]) return
-    var users = []
-    Object.keys(notes[noteId].users).forEach(function (key) {
-      var user = notes[noteId].users[key]
-      if (user) {
-        users.push(buildUserOutData(user))
-      }
-    })
-    var out = {
-      users: users
-    }
-    socket.emit('online users', out)
-  })
 }
 
 exports = module.exports = realtime

test/realtime.test.js

@@ -446,7 +446,7 @@ describe('realtime', function () {
 
   describe('socket event', function () {
     let realtime
-    const noteId = "note123"
+    const noteId = 'note123'
     let clientSocket
     const eventFuncMap = new Map()
     beforeEach(() => {
@@ -572,7 +572,7 @@ describe('realtime', function () {
       })
     })
 
-    ;['cursor focus', 'cursor activity', 'cursor blur'].forEach( (event) => {
+    ;['cursor focus', 'cursor activity', 'cursor blur'].forEach((event) => {
       describe(event, function () {
         let cursorFocusFunc
 
@@ -626,5 +626,34 @@ describe('realtime', function () {
       })
     })
 
+    describe('online users', function () {
+      it('should return online user list', () => {
+        const onlineUsersFunc = eventFuncMap.get('online users')
+        realtime.notes[noteId] = {
+          users: {
+            10: {
+              id: 10
+            },
+            20: {
+              id: 20
+            }
+          }
+        }
+        onlineUsersFunc()
+        assert(clientSocket.emit.called)
+        assert(clientSocket.emit.lastCall.args[0] === 'online users')
+        let returnUserList = clientSocket.emit.lastCall.args[1].users
+        assert(returnUserList.length === 2)
+        assert(returnUserList[0].id === 10)
+        assert(returnUserList[1].id === 20)
+      })
+
+      it('should not return user list when note not exists', () => {
+        const onlineUsersFunc = eventFuncMap.get('online users')
+        onlineUsersFunc()
+        assert(clientSocket.emit.called === false)
+      })
+    })
+
   })
 })