💬 Chat Application Using Erlang

📌 Overview

A scalable chat application built in Erlang, leveraging in-memory data structures and Mnesia DBMS for storing messages, chat history, and offline messages. The application evolves in multiple versions with enhanced features.

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🚀 Versions

✅ Version 1: Basic Chat System

• Implemented using Erlang with in-memory data structures for storing messages and history.

✅ Version 2: Persistent Storage

• Integrated Mnesia DBMS for storing messages, history, and offline messages.

⏳ Version 3: Upcoming (OTP Gen_Server)

• Upgrading to OTP Gen_Server for improved concurrency and fault tolerance.

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🏗 Tech Stack

Component	Technology Used
Backend	Erlang
Database	Mnesia DBMS
Concurrency	OTP (Upcoming)

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⚡ App Start Commands

🖥️ Server Terminal

# Start Server Terminal with name "server"
erl -sname server   

# Compile server and client files
c(server).
c(client).  

# Start Server with Max Users Allowed Count
server:start(Server_Name, 0, MaxUsersAllowedCount).

🖥️ Client Terminal

# Start Client Terminal with name "client"
erl -sname client   

# Connect Client Terminal to Server Terminal
net_kernel:connect_node(Server_Name).  

# Compile server and client files
c(server).  
c(client).

# Start Client with a username
client:start(Server_Name, UserName).

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🛠 App Functionality Commands

🔹 Server Commands

Command	Description
server:get_history(Server_Name).	Get chat history
server:get_connected_clients(Server_Name).	Get list of connected clients
server:send_message_to_all_clients(Server_Name, "Hello Everyone").	Broadcast message to all clients
server:make_admin(Server_Name, UserName).	Assign admin privileges to a user

🔹 Client Commands

Command	Description
client:send_message(Server_Name, UserName, "hi").	Send message to chat room
client:exit(Server_Name, UserName).	Exit chat room
client:send_private_message(Server_Name, ReceiverUserName, SenderUserName, "hi").	Send private message
client:get_connected_clients(Server_Name, UserName).	Get list of connected clients
client:update_chat_topic(Server_Name, UserName, "New Topic").	Update chat room topic
client:get_current_chat_topic(Server_Name, UserName).	Get current chat room topic
client:perform_admin_action(Server_Name, AdminUserName, UserName, mute, 5).	Mute/unmute/kick/make admin
client:get_admins(Server_Name, UserName).	Get list of admins
client:set_status(Server_Name, UserName, offline).	Update user status

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🔗 Future Enhancements

• ✅ Implement OTP Gen_Server for better fault tolerance
• ✅ Improve message persistence for scalability
• ✅ Introduce user authentication and encryption for security
• ✅ Build a web interface for easier interactions

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🤝 Contributing

We welcome contributions! Feel free to fork, open issues, and submit pull requests.

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📜 License

This project is licensed under the MIT License.

💡 Built for learning, optimized for performance! 🚀