aioflask

Flask running on asyncio!

WARNING: This is an experiment at this point. Not at all production ready!

Quick start

To use async view functions and other handlers, use the aioflask package instead of flask.

The aioflask.Flask class is a subclass of flask.Flask that changes a few minor things to help the application run properly under the asyncio loop. In particular, it overrides the following aspects of the application instance:

• The route, before_request, before_first_request, after_request, teardown_request, teardown_appcontext, errorhandler and cli.command decorators accept coroutines as well as regular functions. The handlers all run inside an asyncio loop, so when using regular functions, care must be taken to not block.
• The WSGI callable entry point is replaced with an ASGI equivalent.
• The run() method uses uvicorn as web server.

There are also changes outside of the Flask class:

• The flask run command starts the uvicorn web server.
• The render_template() function is asynchronous and must be awaited. The sync render version is available as render_template_sync().

Example

import asyncio
from aioflask import Flask

app = Flask(__name__)

@app.route('/')
async def index():
    await asyncio.sleep(1)
    return "Look Ma, I'm async!"