The lightning-fast ASGI server.
Documentation: https://www.uvicorn.org
Community: https://discuss.encode.io/c/uvicorn
Requirements: Python 3.6+ (For Python 3.5 support, install version 0.8.6.)
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.
Quickstart
Install using pip
:
$ pip install uvicorn
This will install uvicorn with minimal (pure Python) dependencies.
$ pip install uvicorn[standard]
This will install uvicorn with "Cython-based" dependencies (where possible) and other "optional extras".
In this context, "Cython-based" means the following:
- the event loop
uvloop
will be installed and used if possible. - the http protocol will be handled by
httptools
if possible.
Moreover, "optional extras" means that:
- the websocket protocol will be handled by
websockets
(should you want to usewsproto
you'd need to install it manually) if possible. - the
--reloader
flag in development mode will usewatchgod
. - windows users will have
colorama
installed for the colored logs. python-dotenv
will be installed should you want to use the--env-file
option.PyYAML
will be installed to allow you to provide a.yaml
file to--log-config
, if desired.
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.
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