Using decoration stack to decorate an existing service? - php

Question

Symfony docs show a very neat way to create a stack of decorators:
namespace Symfony\Component\DependencyInjection\Loader\Configurator;
return function(ContainerConfigurator $container) {
$container>stack('decorated_foo_stack', [
inline_service(\Baz::class),
inline_service(\Bar::class),
inline_service(\Foo::class),
])
;
};
And show this as an alternative to doing:
// config/services.php
namespace Symfony\Component\DependencyInjection\Loader\Configurator;
return function(ContainerConfigurator $configurator) {
$services = $configurator->services();
$services->set(\Foo::class);
$services->set(\Bar::class)
->decorate(\Foo::class, null, 5)
->args([service('.inner')]);
$services->set(\Baz::class)
->decorate(\Foo::class, null, 1)
->args([service('.inner')]);
};
Problem is, the "neater" approach leaves service Foo::class undecorated. Applications that use the original definition do not go through the stack, but access the original service.
In my case, I have to decorate a service called api_platform.serializer.context_builder. Doing this works in creating a decorated stack:
$services->stack(
'decorated_context_builder',
[
inline_service(SupportTicketMessageContextBuilder::class),
inline_service(LeadContextBuilder::class),
inline_service(BidContextBuilder::class),
inline_service(PartnerContextBuilder::class),
inline_service(WebProfileContextBuilder::class),
service('api_platform.serializer.context_builder'),
]
);
The service is provided by a vendor dependency, and it's used by that dependency. When it uses the injected api_platform.serializer.context_builder it completely ignores my newly created decorated_context_builder stack.
Instead, if I create the stack manually:
$services->set(LeadContextBuilder::class)
->decorate('api_platform.serializer.context_builder', priority: 4)
;
$services->set(BidContextBuilder::class)
->decorate('api_platform.serializer.context_builder', priority: 3)
;
// etc, etc, etc
... it works as expected.
How can I use a decoration stack to decorate an existing service definition, so that the existing definition gets decorated?

Answer 1

Apparently this is not possible with stacking decorators, as they are not currently compatible with decorating other services, just to create stand-alone stacks.