Chatzz

A NodeJS + Socket.IO based framework for creating a chat application.

How to install

npm install chatzz --save

How to Use ?

var express = require('express');
var mongoose = require('mongoose');
var app = express();
var server = require('http').Server(app);

mongoose.connect('mongodb://localhost/chatzz-db').then(function() {
    chatzz.init(server, [chatzzConfig]);
});
...  // configure your express server here
...   
...
server.listen(port, function() {
    console.log('server started on port', port);
});

Documentation

• ChatzzConfig Chatzz config is simple object with following properties

  1. userModeName (default: 'User'): It is the name of your user's model
  2. chatUserModelName (default: 'ChatUser'): It is a collection created by Chatzz to maintain list of Chat Users
  3. beforeSendingUserDetails : It is the function which returns a promise. This function is called when populating the user object residing in ChatUser document. By default this function just simply populate the first level properties of the User model.

• Events Events are the heart of Socket.IO, these events are used for the communication between Client and Server and vice versa.

  Event emitted by server

  Server will always return data by emitting event chatzz and every chatzz event will send a JSON object as data with two fields in it.

  1. type : an enum which can have possible values of user-details, chat-user-status-changed, new-message, message-status-changed and old-messages.
  2. data: a JSON object with containing data relevant to the emitted event type.

  Events emitted by Client

  1. connect-user: emit this event from client side to register the user in the chat system with this data { userId: // userId of logged in user }.

  Server will emit chatzz event with following details to the user who just logged in

  {
    type: 'user-details',
    data: {
      user: { // user details },
      status: 'online' or 'offline',
      lastOnline: 'date-time string',
      connectedUsers: [
        // array of users object connected to the requesting user + chatRoomId
      ],
      missedMessages: {
        'userId1': [
          // messages missed from user user1
        ],
        'userId2': [
          // message Ids missed from user user2
        ]
      }
    }
  }
  

  Server will also emit chatzz event with following data for all the connectedUsers who is connected to the user who just logged in.

  {
   type: 'user-status-changed`,
   data: {
     lastOnline: // date-time string
     status: 'online',
     user: {
       // user details of this user who just disconnected
     }
   } 
  }
  

  2. add-chat-user: Client should emit this event when the corresponding user wants to add another user as its connectedUser (see connectedUser field in object returned from server on emitting user-details event) to from client side to register the user in the chat system with this data { userToAdd: <user id of another user> } and an error first callback

  Server will emit a chat-user-added event destined userToAdd user as follows.

  {
    type: 'chat-user-added`,
    data: {
      // details of user requested to **userToAdd** user
      lastOnline: // date-time string
      status: 'online'
    } 
  }
  

  3. get-old-messages: Client should emit this event when it wants to fetch old messages from chat with another user with following data.

  { 
    userId: // userId of another user
    [date]: // date from which you want to your messages
  } 
  

  Server will emit chatzz event with following details

  {
    type: 'old-messages,
    data: [
      //array of message object
      {
        _id: // object id of the message,
        createdAt: //date-time string representing when the message was created,
        from: { //user details of User who sent this message},
        to: { // user details of User to whom the message was sent },
        message: //actual message',
        status: // could be any one of 'not_sent', 'sent' or 'read'
      }
    ]
  } 
  

  4. send-message: Client should emit this event with following data when it wants to send a message to another user.

  { 
    userId: //user id of another user
    message: //message string which Client wants to send
  } 
  

  Server will emit chatzz event with following details Server will emit two events one for sender and one for receiver with following data

  {
   type: 'new-message'
   data: {
     _id: // object id of the message,
     createdAt: //date-time string representing when the message was created,
     from: { //user details of User who sent this message},
     to: { // user details of User to whom the message was sent },
     message: //actual message',
     status: // could be any one of 'not_sent', 'sent' or 'read'
   } 
  }
  

  5. message-read: Client should emit this event with following data when it wants to notify the server that it has read the message.

  { 
    messageId: //id of the message about which Client wants to notify the Server
  } 
  

  Server will emit a chatzz event for sender of this message with following data

  {
   type: 'message-status-changed`,
   data: {
     _id: // object id of the message,
     createdAt: //date-time string representing when the message was created,
     from: { //user details of User who sent this message},
     to: { // user details of User to whom the message was sent },
     message: //actual message',
     status: 'read'
   } 
  }
  

  5. disconnect: Client should emit this event when it want to notify the Server that it is leaving.

  // no data is required 
  

  Server will emit a chatzz event for all connectedUsers of this user with following data

  {
   type: 'user-status-changed`,
   data: {
     lastOnline: // date-time string,
     status: 'offline',
     user: {
       // user details of this user who just disconnected
     }
   } 
  }