uvicorn definition


The lightning-fast ASGI server.

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Documentation : https://www.uvicorn.org

Requirements : Python 3.5, 3.6, 3.7

Uvicorn is a lightning-fast ASGI server implementation, using uvloop and httptools .

Until recently Python has lacked a minimal low-level server/application interface for asyncio frameworks. The ASGI specification fills this gap, and means we’re now able to start building a common set of tooling usable across all asyncio frameworks.

Uvicorn currently supports HTTP/1.1 and WebSockets. Support for HTTP/2 is planned.


Install using pip :

$ pip install uvicorn

Create an application, in example.py :

async def app(scope, receive, send):
    assert scope['type'] == 'http'

    await send({
        'type': 'http.response.start',
        'status': 200,
        'headers': [
            [b'content-type', b'text/plain'],
    await send({
        'type': 'http.response.body',
        'body': b'Hello, world!',

Run the server:

$ uvicorn example:app

Uvicorn is BSD licensed code.Designed & built in Brighton, England.— 🦄 —