![]() | The topic of this article may not meet Wikipedia's general notability guideline .(December 2023) |
Version | 3.0 |
---|---|
Developer | ASGI Team |
Release date | 2019-03-04 [1] |
Website | asgi |
License | public domain [2] |
Status | Draft |
The Asynchronous Server Gateway Interface (ASGI) is a calling convention for web servers to forward requests to asynchronous-capable Python frameworks, and applications. It is built as a successor to the Web Server Gateway Interface (WSGI).
Where WSGI provided a standard for synchronous Python application, ASGI provides one for both asynchronous and synchronous applications, with a WSGI backwards-compatibility implementation and multiple servers and application frameworks.
An ASGI-compatible "Hello, World!" application written in Python:
asyncdefapplication(scope,receive,send):event=awaitreceive()...awaitsend({"type":"websocket.send",...})
Where:
application
, which takes three parameters (unlike in WSGI which takes only two), scope
, receive
and send
. scope
is a dict
containing details about current connection, like the protocol, headers, etc.receive
and send
are asynchronous callables which let the application receive and send messages from/to the client.await
keyword is used because the operation is asynchronous.ASGI is also designed to be a superset of WSGI, and there's a defined way of translating between the two, allowing WSGI applications to be run inside ASGI servers through a translation wrapper (provided in the asgiref library). A threadpool can be used to run the synchronous WSGI applications away from the async event loop.
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