On 23/12/2023 20:34, Kévin Dunglas wrote:
In addition to sharing code, maintenance, performance optimization, etc.,
the existence of a common infrastructure would standardize the way worker
scripts are created and provide a high-level PHP API for writing worker
scripts that work with all SAPIs that rely on this new feature.
While this seems like a noble aim, there doesn't seem to be much
consensus on what such an API should look like; from what I can see:
- FrankenPHP expects the user to manage the main event loop, repeatedly
passing the server a function to be called once; it doesn't pass
anything into or out of the userland handler, instead resetting global
state to mimic a non-worker environment
[https://frankenphp.dev/docs/worker/#custom-apps]
- RoadRunner doesn't use a callback at all, instead providing methods to
await a request and provide a response; it directly uses PSR-7 and
PSR-17 objects [https://roadrunner.dev/docs/php-worker/current/en]
- OpenSwoole manages the main loop itself, and uses lifecycle events to
interface to userland code; the HTTP 'Request' event is passed custom
Request and Response objects
[https://openswoole.com/docs/modules/swoole-http-server-on-request]
It also seems relevant to mention the situation in Python:
- WSGI specifies a Python-level interface between a web server and a web
application / framework. The server side is expected to provide the
event loop (unlike in FrankenPHP), and passes the application an
environment dictionary (based on CGI) and a start_response callback.
[https://peps.python.org/pep-3333/]
- The newer ASGI generalises this interface into an asynchronous event
handling system, including support for WebSockets.
[https://asgi.readthedocs.io/en/latest/introduction.html]
Out of all of these, the FrankenPHP approach seems to be the most basic,
providing good backwards compatibility with PHP's normal "shared
nothing" approach, but not much forwards compatibility - I can't see how
it would be adapted for an async PHP environment, or with WebSockets,
for instance. I'm sceptical how many SAPIs would actually implement it,
rather than providing more powerful APIs.
Regards,
--
Rowan Tommins
[IMSoP]
