pallets/quart

Quart

Quart is an async Python web application framework. Using Quart you can,

• render and serve HTML templates,
• write (RESTful) JSON APIs,
• serve WebSockets,
• stream request and response data,
• do pretty much anything over the HTTP or WebSocket protocols.

Quickstart

Install from PyPI using an installer such as pip.

$ pip install quart

Save the following as app.py. This shows off rendering a template, returning JSON data, and using a WebSocket.

from quart import Quart, render_template, websocket

app = Quart(__name__)

@app.route("/")
async def hello():
    return await render_template("index.html")

@app.route("/api")
async def json():
    return {"hello": "world"}

@app.websocket("/ws")
async def ws():
    while True:
        await websocket.send("hello")
        await websocket.send_json({"hello": "world"})

$ quart run
 * Running on http://127.0.0.1:5000 (CTRL + C to quit)

To deploy this app in a production setting see the deployment documentation.

Contributing

Quart is developed on GitHub. If you come across a bug, or have a feature request, please open an issue. To contribute a fix or implement a feature, follow our contributing guide.

Help

If you need help with your code, the Quart documentation and cheatsheet are the best places to start. You can ask for help on the Discussions tab or on our Discord chat.

Relationship with Flask

Quart is an asyncio reimplementation of the popular Flask web application framework. This means that if you understand Flask you understand Quart.

Like Flask, Quart has an ecosystem of extensions for more specific needs. In addition, a number of the Flask extensions work with Quart.

Migrating from Flask

It should be possible to migrate to Quart from Flask by a find and replace of flask to quart and then adding async and await keywords. See the migration documentation for more help.