Allow empty body for POST and PUT requests

[kbsali]

Right now it is not possible to POST or PUT requests without specifying at least an empty object.
While this is correct for most of the use case, we've had to add a listener to bypass this for new PUT entry points we are creating which "carries" the change to be applied to our object.
eg. PUT /api/blog_posts/[id]/publish

Here is a "serious" source showing that this is perfectly fine : http://lists.w3.org/Archives/Public/ietf-http-wg/2010JulSep/0276.html :)

Do you agree? If you do, I will try to submit a PR asap, otherwise i'll live with our custom listener...

[teohhanhui]

I think your solution is fine because we're talking about custom operations anyway.

Yes, I myself have run into this problem too when I implemented a POST /products?copyOf=/products/1 to clone a resource (sending empty body).

[teohhanhui]

But it'd be good if we can take care of this automatically, i.e. don't try to deserialize if body is empty.

Still, what if a media type attaches some meaning to an empty body?

[kbsali]

@teohhanhui so do you think a PR would be acceptable for this? :)

[teohhanhui]

Yes please.

[teohhanhui]

Just adding a check here should do:

core/src/EventListener/DeserializeListener.php

Lines 66 to 71 in f1a6537

	$request->attributes->set(
	'data',
	$this->serializer->deserialize(
	$request->getContent(), $attributes['resource_class'], $format, $context
	)
	);

[kbsali]

closing as this has been apparently discarded!
too bad... i don't understand why it was ok to do this to start with, and once a PR was submitted, it was discarded. :-(

[dunglas]

@kbsali I'm still ok to merge it, we just need to finish it.

[teohhanhui]

I suggest decorating the listener, like https://github.com/api-platform/docs/blob/e698aef1b147e94190dc189471b1c4b093545856/core/form-data.md

(It's already possible to cleanly decorate event listeners since symfony/symfony#20207 - see discussion in symfony/symfony#19697. The documentation needs to be updated to reflect that.)