This project implements a concurrent message broker using C++ with some object-oriented programming (OOP). The message broker allows clients to subscribe to topics, publish messages, and receive messages from subscribed topics.

• Subscription: Clients can subscribe to specific topics to receive messages.

• Publishing: Clients can publish messages to specific topics, which are then delivered to subscribed clients.

• Unsubscription: Clients can unsubscribe from topics to stop receiving messages.

• The server has a simple thread per client concurrency.

• server.cpp: Contains the implementation of the server, which handles client connections and message routing.
• handlers.cpp and handlers.h: Define the command handlers for different commands like SUB, PUB, UNSUB, and PING.
• parser.h: Implements the command parser, which creates command handlers based on received commands.
• server.h: Header file for the server class.

mkdir build + cd build + make

./server

Clients can connect to the server using a socket connection. For testing purposes, you can use tools like telnet or create a simple client in C++.

telnet localhost 4222

SUB my_topic

PUB my_topic 8 "Hello!" and we get: Hello! as the subscribers too (In this case our client is both the subscriber and the publisher), you can open another terminal and connect with a different client and experience it

Unsubscribe from a Topic: UNSUB my_topic

AbsractHandler: Abstract base class for command handlers, defining the common interface.
SubCommandHandler, PubCommandHandler, UnsubCommandHandler, PingCommandHandler: Concrete implementations of command handlers.
CommandParser: Responsible for creating the appropriate command handler based on the received command.

Feel free to contribute to the project by opening issues or creating pull requests. Your feedback and contributions are highly appreciated!