Unable to convert self-referring instances to resources

[tobias-trozowski]

Q	A
Documentation	yes
Bugfix	yes (#1)
BC Break	yes
New Feature	no
RFC	no
QA	no

Description

• Are you fixing a bug?
  • Detail how the bug is invoked currently.
  • Detail the original, incorrect behavior.
  • Detail the new, expected behavior.
  • Add a regression test that demonstrates the bug, and proves the fix.

$parent = new TestAsset\FooBar;
$parent->id = 1234;
$parent->foo = 'FOO';
$parent->bar = $parent;

$generator->fromObject($parent, $request);
// the call above will result in an error:
// Error : Maximum function nesting level of '256' reached, aborting!

Additional examples:
One-To-One, Bidirectional
One-To-One, Self-referencing
One-To-Many, Bidirectional
One-To-Many, Self-referencing
Many-To-Many, Bidirectional
Many-To-Many, Self-referencing

The zfcampus/zf-hal component solved this issue by using a $maxDepth property in metadata which is then passed through here and here.

Using this approach will result in a change of the \Zend\Expressive\Hal\ResourceGenerator\StrategyInterface interface which is a BC break.

This PR is based on my original PR in zend-expressive-hal.

The following public methods changed (added new argument int $depth with default value)

• Metadata\RouteBasedResourceMetadata::__construct
• ResourceGenerator::fromObject
• ResourceGenerator\StrategyInterface::createResource
• ResourceGenerator\RouteBasedCollectionStrategy::createResource
• ResourceGenerator\RouteBasedResourceStrategy::createResource
• ResourceGenerator\UrlBasedCollectionStrategy::createResource
• ResourceGenerator\UrlBasedResourceStrategy::createResource

[weierophinney]

This will need to target 2.0.0. I'm creating a 2.0.x branch now, and will rebase this against it for you momentarily.

[weierophinney]

This is a BC break. Classes extending this one and defining using the previous signature will produce a warning under PHP 7, and a fatal under PHP 8, due to signature mismatch. We'll need to target next major for this.