Instant Messaging Server

Description

This is a server dedicated to the terminal for instant messaging. It allows the clients to do the following:

• Send a message to a specific user / group
• Retrieve all the groups that the user is a part of

Features to be implemented

• (Half-way) Create a group with different users
• Query the messages of the recent 10 messages of a chat channel (i.e. user or group)
• (Client-side) Establish a connection with the server, and subscribe to a path to receive messages (i.e. /chat/messages/<username>)

Dependencies

For python-client, please install:

$ pip install stomp.py websocket-client

Project Structure

• python-client/main.py: Contains a mock client implementation of the server. It connects with the websocket server of this project and sends messages to the server to test the server functionalities.
• controller/: Contains the controllers for the server, handles all the web requests and responses. For example, if a GET request is made to /chat/messages/<username>, the controller will handle the request and return the messages of the user.
• service/: Contains the services for the server, handles all the business logic. For example, if a user wants to send a message to another user, the controller will pick up the request, and call the service functions for the implementation of the logic.
• repository/ : Contains the repository for the server, handles all the database operations. For example, if a user wants to send a message to another user, the service will call the repository functions to store the message in the database.
• model/: Contains the models for the server, handles all the data structures. For example, if a user wants to send a message to another user, the service will call the model functions to create a message object. In short, it basically stores all the schema of all data, including message payload, database schema, etc.
• config/: Contains the configuration for the server, handles all the server configurations for WebSockets, i.e. opening up the relevant

Logic and paths

If the clients want to connect with the server, the relevant endpoint would be (assume the server is hosted locally and port is 8080):

http://localhost:8080/connect/chat

If the clients want to subscribe messages from the server, the relevant endpoint would be:

http://localhost:8080/subscribe/chat/message/<username>

If the server publish messages through SimpMessagingTemplate, the relevant path would be:

/publish/chat/message/<username>

If the clients want to create a group, the relevant endpoint would be:

POST http://localhost:8080/chat

If the clients want to send a message to a person, include the payload in the following path:

POST http://localhost:8080/chat/message

If the clients want to retrieve all the groups that the user is a part of, the relevant endpoint would be:

GET http://localhost:8080/chat/chatRoom/<username>

If the clients want to retrieve the messages of the recent 10 messages of a chat channel (i.e. user or group), the relevant endpoint would be:

GET http://localhost:8080/chat/messages/<chatChannelId>