Enh: Introduce FindInstanceInterface - Part 1.b: TagDependency

[martin-rueegg]

Introduce FindInstanceInterface

Part 1.b Adding TagDependency to cached instances

FindInstanceInterface series:

• Enh: Introduce FindInstanceInterface - Part 1.a: Creating base classes #6503
• Enh: Introduce FindInstanceInterface - Part 1.b: TagDependency  #6528
• Enh: Introduce FindInstanceInterface - Part 2: Implementing throughout the code #6463

Also see:

• Enh: Introduce FindInstanceInterface - Part 1.a: Creating base classes #6503 (comment)
• Enable RuntimeCache during tests #6527 (comment)

I've found a way do enable cache dependencies while not using a serializer ...

'runtimeCache' => [
	'class' => \yii\caching\ArrayCache::class,
	'serializer' => [
		static fn &($input) => $input,
		static fn &($input) => $input,
	],
],

TagDependencies only work if a serializer is used. Either the default PHP-internal serializer, or a user-provided. If serialization is disabled, they will not work.

Now since it would be unnecessary effort to serialize and unserialize runtime-cached items (which we all agree), serializing was disabled in common.php. This makes sense. However, the side effect of setting ['serializer' => false] is, that TagDependencies are disabled.

My suggested solution is, that we provide a user-defined serializer (an array of a serializing and unserializing function) which in both cases just return the value as-is. As such, the cache implementation thinks it does serializing, while actually, it doesn't.

Note: This trick only works for ArrayCache, not e.g. FileCache. So who ever decides to use a different Cache implementation for the runtime cache, needs to be aware of that.