UP Chat

Introduction

UPChat is a simple chat service that serves as an alternative to instant messaging services already known. It allows authentication with third-party APIs and messages exchange with your friends in the respective API used.

This is a simple implementation developed with NodeJS (server) and Java (client) for Distributed Systems discipline at the Faculty of Engineering of the University of Porto.

Service

The service uses a client-server model mainly built over a TCP connection, only requires that the client is able to perform an HTTP request to authenticate.

A client is a program that establishes a connection to a server for the purpose of to authenticate using third-party API, retrieve personal information, friends list and chat with another client. A server is a program that accepts connections in order to handle with clients' personal information and chats.

The chat service herein described is designed to hide the details of implementation by presenting a standard message exchange between the client and the server. In this way, each client or server is free to choose its own technology stack.

Protocol specification

The protocol used by the chat service comprises some smaller subprotocols which are used for specific tasks: authentication, account operations and chatting. In addiction, it is composed of a single line header followed by an optional multiple line body.

Message format:

HEADER CRLF CRLF BODY

Authentication Protocol with facebook, twitter and google

This protocol specifies in detail the message exchange to be done between the tcp (main communication server) and http (server for login purposes) servers and the java application(client).

LOGIN_SUCCESS

• Sender: HTTP Server
• Receiver: TCP Server

Message format:

HEADER
LOGIN_SUCCESS <login type> <client name>
BODY
<client informations>

LOGIN_ERROR

• Sender: HTTP Server
• Receiver: TCP Server

Message format:

HEADER
LOGIN_ERROR <login type>

BODY
-

Authentication Protocol

This protocol specifies in detail the message exchange to be done between the tcp server (main communication server) and the java application(client).

LOGIN_REQUEST

• Sender: Client
• Receiver: TCP Server

Message format:

HEADER
LOGIN_REQUEST <username> <password>
BODY
-

LOGIN_SUCCESS

• Sender: TCP Server
• Receiver: Client

Message format:

HEADER
LOGIN_SUCCESS
BODY
<online_friends>

LOGIN_ERROR

• Sender: HTTP Server
• Receiver: TCP Server

Message format:

HEADER
LOGIN_ERROR
-

BODY
-

UPDATE_FRIENDS

• Sender: TCP Server
• Receiver: Client

Message format:

HEADER
UPDATE_FRIENDS
BODY
<online friends>

Chatting Protocol

Description.

MESSAGE_TO

• Sender: Client
• Receiver: TCP Server

Message format:

HEADER
MESSAGE_TO <friend`s username>

BODY
<message content>

MESSAGE_FROM

• Sender: TCP Server
• Receiver: Client

Message format:

HEADER
MESSAGE_FROM <friend`s username>

BODY
<message content>

Run

• Install Node.js v6.10.3

• Go to /path/to/upchat

• Configure server/index.js

  • Set tcpServer host IP:PORT

• Run server/index.js

• Configure client/java/src/connection/ChatApp

  • Set Socket host IP:PORT

• Run ChatApp

Authors

• João Fernandes - github
• Joel Carneiro - github
• Rúben Marques - github

License

This project is licensed under the MIT License - see the LICENSE.md file for details.