Local-Messaging-App

It uses python flask to create a server which san be used to communicate multiple devices connected to the same serevr. It provides three group ans indivisual messsage service

• admin
• staff
• client

Required modules

• Flask module pip install Flask
• Flask-socket.io module pip install flask-socketio Make sure you have installed the following modules before executing the app.py file

app.py File

from flask import Flask, render_template, request
from flask_socketio import SocketIO, emit
from datetime import datetime

app = Flask(__name__, static_url_path='/static')
app.config['SECRET_KEY'] = 'secret!'
socketio = SocketIO(app)

users = {}

admin_list = []
staff_list = []
client_list = []

@app.route('/admin/<username>')
def admin_page(username):
    return render_template('admin.html', username=username, user_type='admin')

@app.route('/staff/<username>')
def staff_page(username):
    return render_template('staff.html', username=username, user_type='staff')

@app.route('/client/<username>')
def client_page(username):
    return render_template('client.html', username=username, user_type='client')

@socketio.on('connect')
def connect():
    # scrap the basic details
    user_ip = request.remote_addr
    user_sid = request.sid

    # save user information
    users[user_sid] = {'IP':user_ip, 'Connected_at':datetime.now().strftime("%Y-%m-%d %H:%M:%S"), 'Varification':'NOT VERIFIED', 'user_type':'NULL'}

    # display connection successful message
    print(f'User connected [NOT VERIFIED] {user_ip}\t{user_sid}')

    for admin in admin_list + staff_list + client_list:
        emit('update_web_app', {'message':'USER CONNECTED', 'users':users}, room=admin)

@socketio.on('verify_user')
def verify_user(data):
    # scrap the basic details 
    user_ip = request.remote_addr
    user_sid = request.sid
    user_type = data['user_type']
    user_name = data['user_name']

    users[user_sid]['user_type'] = user_type
    users[user_sid]['user_name'] = user_name

    # filter the user_type
    if user_type == 'admin':
        # add user into into group
        admin_list.append(user_sid)
        # display user connection verification successful
        print(f'Connected user [VERIFIED] {user_ip}\t{user_sid}')
        users[user_sid]['Varification'] = 'VERIFIED'
    elif user_type == 'staff':
        staff_list.append(user_sid)
        print(f'Connected user [VERIFIED] {user_ip}\t{user_sid}')
        users[user_sid]['Varification'] = 'VERIFIED'
    elif user_type == 'client':
        client_list.append(user_sid)
        print(f'Connected user [VERIFIED] {user_ip}\t{user_sid}')
        users[user_sid]['Varification'] = 'VERIFIED'
    else:
        print(f'Connected user [NOT AUTHORISED] {user_ip}\t{user_sid}')
        users[user_sid]['Varification'] = 'NOT AUTHORISED'

    emit('update_web_app', {'message':'USER CONNECTED', 'users':users}, broadcast=True)
'''
    for admin in admin_list:
        emit('update_web_app', {'message':'USER CONNECTED', 'users':users}, room=admin)
'''
@socketio.on('disconnect')
def disconnect():
    # scrap the basic details
    user_ip = request.remote_addr
    user_sid = request.sid

    user_type = users[user_sid]['user_type']
    verification_status = users[user_sid]['Varification']

    # save user information
    users.pop(user_sid)

    # display connection successful message
    print(f'User disconnected {user_ip}\t{user_sid}\t{user_type}\t{verification_status}')

    emit('update_web_app', {'message':'USER CONNECTED', 'users':users}, broadcast=True)
'''
    for admin in admin_list + staff_list + client_list:
        emit('update_web_app', {'message':'USER CONNECTED', 'users':users}, room=admin)
'''    
@socketio.on('send_message')
def send_message(data):
    # scrap basic details
    sender_sid = request.sid
    recipients = data['recipients']
    message = data['message']

    # filter the recipient group
    if recipients == 'admin':
        for admin in admin_list:
            # send message to all the group members
            emit('message_from_user', {'message':message, 'sender':sender_sid, 'sender_name':users[sender_sid]['user_name']}, room=admin)
    elif recipients == 'client':
        for client in client_list:
            emit('message_from_user', {'message':message, 'sender':sender_sid, 'sender_name':users[sender_sid]['user_name']}, room=client)
    elif recipients == 'staff':
        for staff in staff_list:
            emit('message_from_user', {'message':message, 'sender':sender_sid, 'sender_name':users[sender_sid]['user_name']}, room=staff)
    else:
        # if recipient group is neither admin, staff not client
        emit('message_from_user', {'message':message, 'sender':sender_sid, 'sender_name':users[sender_sid]['user_name']}, room=recipients)

if __name__ == '__main__':
    socketio.run(app, debug=True, host='0.0.0.0', port=8080)

Javascript Codes

• Add these codes in your <head> tag

// Connect the user to the server
var socket = io.connect(`server_url`);

// 1. Connect event
socket.on('connect', function () {
    console.log('Connected to server');
});

// 2. Verify user event
socket.on('verify_user', function (data) {
      console.log('User verified:', data);
});

// 4. message_individual event
socket.on('message_from_user', function (data) {
      console.log('Received individual message:', data);
});

// send message  
function send_message(message, recipients) {
    socket.emit('send_message', { message: message, recipients: recipients });
}

// Function to emit verify_user event
function verifyUser(userType) {
    socket.emit('verify_user', { user_type: `user_type`, user_name: `user_name` });
}

// call the function when App loads
window.addEventListener('load', function () {
    verifyUser();
});

// handle the received update_web_app message 
socket.on('update_web_app', function (data) {
    console.log('Received message:', data); // log the message received
});

• remember to replace and handle the valiables user_type, user_name and server_url.

Important

• executing the main app.py file directly don't need any modification in the webpages.
• For your own use you can modify the file as per your need.
• For users their app will be serving at the url like localhost:8080/user_type/user_name where usertype may be admin, staff or client.

Screenshots

• 
• 

Install

Install dependencies:

pip install -r requirements.txt

Run (Flask / SocketIO)

Run the existing Flask app:

python app.py

Default URL patterns:

• http://localhost:8080/admin/<username>
• http://localhost:8080/staff/<username>
• http://localhost:8080/client/<username>

FastAPI Rooms (Shareable URL chat)

This repository also includes a separate FastAPI + WebSocket based room chat app under fastapi_chat/.

Features

• Create a room and get a shareable URL
• Optional room passwords (protected rooms)
• Anyone opening the URL can send/receive messages
• Messages are broadcast to all connected users in the room

Run

python -m uvicorn fastapi_chat.main:app --host 0.0.0.0 --port 8090 --reload

Open:

• http://localhost:8090/

Usage

Create an open room

• Open http://localhost:8090/
• Leave Optional password empty
• Click Create room
• Share the generated room link

Create a password-protected room

• Open http://localhost:8090/
• Set a value in Optional password
• Click Create room
• Share the generated room link

When someone opens the room link, they will be prompted to enter the room password before they can chat.

API / Protocol

REST

• POST /api/rooms
  • Body (JSON): { "password": "..." } (optional; omit or set empty for open rooms)
  • Response: { "room_id": "...", "room_url": "..." }
• GET /api/rooms/{room_id}
  • Response: { "room_id": "...", "protected": true|false }

WebSocket

• Connect to: ws(s)://<host>/ws/{room_id}
• If the room is protected, the server will send:
  • { "type": "auth_required" }
  • Client must respond with:
    • { "type": "auth", "password": "..." }
  • On success, server sends:
    • { "type": "auth_ok" }
  • On failure, server sends:
    • { "type": "auth_error", "message": "..." } and closes the socket

After authentication succeeds, the client can send normal messages:

• Chat message: { "type": "chat", "username": "...", "message": "..." }
• Presence update: { "type": "presence", "username": "..." }
• Typing indicator: { "type": "typing", "username": "...", "is_typing": true|false }