python-aiohttpHow to create a websocket server using Python Aiohttp?

Creating a websocket server using Python Aiohttp is easy and straightforward.

import asyncio
from aiohttp import web

async def websocket_handler(request):
    ws = web.WebSocketResponse()
    await ws.prepare(request)

    async for msg in ws:
        if msg.type == web.WSMsgType.text:
            await ws.send_str(msg.data + '/answer')
        elif msg.type == web.WSMsgType.binary:
            await ws.send_bytes(msg.data)
        elif msg.type == web.WSMsgType.close:
            break

    return ws

app = web.Application()
app.add_routes([web.get('/', websocket_handler)])

web.run_app(app)

The code above creates a websocket server using Python Aiohttp. It creates a websocket handler which handles incoming websocket requests. It then adds a route to the application and runs the application.

The code consists of the following parts:

1. Importing the necessary modules: import asyncio and from aiohttp import web
2. Creating a websocket handler: async def websocket_handler(request)
3. Creating a websocket response: ws = web.WebSocketResponse()
4. Preparing the websocket response: await ws.prepare(request)
5. Handling incoming messages: async for msg in ws
6. Sending a response: await ws.send_str(msg.data + '/answer')
7. Creating an application: app = web.Application()
8. Adding a route to the application: app.add_routes([web.get('/', websocket_handler)])
9. Running the application: web.run_app(app)

Helpful links

• Aiohttp Documentation
• Websockets Tutorial

Edit this code on GitHub