🌐 Echat Protocol Documentation

📖 Overview

Echat is a multi-user chat system where clients connect to a central server using a command-based protocol. The server handles:

• 🔒 User authentication
• 🛠️ Room creation and joining
• ✉️ Message distribution
• 🛡️ Administrative operations

💻 Clients use a dedicated Java program to manage socket communication, but also suports Telnet connections.

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🛠️ Communication Basics

• Protocol: TCP
• Default Port: 42069
• Message Format: Plain text strings, ending with \n

🔗 Connection Flow:

1. Clients connect to the server via a TCP socket.
2. Once connected, they can issue commands and receive responses.

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🔑 Command Structure

General Syntax:

<command> [arg1] [arg2] ...

• 📋 Commands: Case-insensitive
• 📂 Arguments: Space-separated
• ✅ Server Responses: Success, error, or informational messages

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✨ Supported Commands

🔑 Authentication

1. Register
   register <username> <password>
   ➡️ Register a new user.

2. Login
   login <username> <password>
   ➡️ Authenticate as an existing user.

🏠 Room Management

• Join Room: join <room_name>
  ➡️ Join a chat room.
• Create Room: createroom <room_name> <PERMS>
  ➡️ Request a new chat room.
• List Rooms: listrooms
  ➡️ View available rooms.
• Leave Room: leave
  ➡️ Exit the current room.

💬 Messaging

• Room Message: Simply type your message.
  ➡️ Sends to everyone in the room.
• Direct Message: msg <username> <message>
  ➡️ Private message another user.

👥 User Management

• List Users: users
  ➡️ View users in the current room.
• Logout: logout
  ➡️ Sign out.

⚙️ Admin Tools (HIGH Permissions)

• Approve Room: approveroom <room_name>
  ➡️ Approve a room creation.
• Deny Room: denyroom <room_name>
  ➡️ Deny a room creation.
• Notify Users: notify <PERMS> <message>
  ➡️ Send notifications to users.

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📜 Permissions Hierarchy

• LOW: Basic users 🟢
• MEDIUM: Intermediate users 🟡
• HIGH: Admin users 🔴

Permissions affect room management, notifications, and approvals.

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🛠️ Example Workflows

1️⃣ Basic User Workflow

1. Register:

   register john password123
   

2. Login:

   login john password123
   

3. Join a Room:

   join General
   

4. Send a Message:

   Hello, everyone!
   

2️⃣ Admin Workflow

1. Login:

   login admin adminpass
   

2. View Pending Requests:

   listroomrequests
   

3. Approve a Room:

   approveroom NewRoom
   

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❌ Error Handling

• Unknown Commands:

  Unknown command. Type help for a list of commands.
  

• Invalid Arguments:

  Invalid command. Usage: <correct usage>
  

• Permission Denied:

  Insufficient permissions to execute this command.