Merge remote-tracking branch 'origin/dev-mongodb' into dev-chat-firebase

app/model/ChatData.js

+class ChatData {
+  constructor () {
+    this.mongoose = require('mongoose')
+    this.mongoose.connect('mongodb://localhost/wbd3_chat')
+
+    this.chatSchema = new this.mongoose.Schema({
+      participant_ids: [Number],
+      chats: [{
+        owner_id: Number,
+        content: String
+      }]
+    })
+    this.ChatModel = this.mongoose.model('Chat', this.chatSchema)
+  }
+
+  addChat (senderId, receiverId, content) {
+    let participantIds = [ senderId, receiverId ]
+    participantIds.sort()
+
+    let chat = {
+      owner_id: senderId,
+      content: content
+    }
+
+    this.ChatModel.findOneAndUpdate(
+      { participant_ids: participantIds },
+      { $push: { chats: chat } }, (err, done) => {
+        if (err) {
+          console.error(err)
+        }
+
+        if (!done) {
+          let chat = new this.ChatModel({
+            participant_ids: participantIds,
+            chats: [{
+              owner_id: senderId,
+              content: content
+            }]
+          })
+
+          chat.save()
+        }
+      })
+  }
+
+  findChat (firstParticipantId, secondParticipantId) {
+    let participantIds = [ firstParticipantId, secondParticipantId ]
+    participantIds.sort()
+
+    this.ChatModel.findOne({ participant_ids: participantIds }, function (err, result) {
+      if (err) {
+        return console.error(err)
+      }
+
+      if (result) {
+        let chats = result.chats
+
+        chats.forEach(function (chat) {
+          console.log(chat)
+        })
+      }
+    })
+  }
+}
+
+module.exports = ChatData