How to inject Service to have a common instance to several clasess them in zend 3 - dependency-injection

Question

In Zend 3, I cannot to figure out how should injections work, let me show some simple example.
Let's say, I have
class ToolCollector implements ToolCollectorInterface {
public function __construct(){}
public function registerTool(ToolInterface $tool){
$this->tools[] = $tool;
}
}
and also
class ToolA implements ToolInterface {
public function __construct(ToolCollectorInterface $mainCollector){$mainCollector->registerTool($this);}
}
so what I expect to have
class SomeController extends AbstractActionController {
public function __construct(ToolCollectorInterface $toolCollector){$this->collector=$toolCollector;}
public function indexAction(){
new ToolA; // <- just call Tool and it will put itself in ToolCollector, this is I want
new ToolB; // <- just call Tool and it will put itself in ToolCollector, this is I want
new ToolC; // <- just call Tool and it will put itself in ToolCollector, this is I want
return ViewModel(['toolNameList'=>$this->collector->getRegisteredToolNames();])
}
}
I tried to make it as shown in example, when i call new ToolA it shows me error 500 without any description.
// Next is works
class ToolControllerFactory implements FactoryInterface
{
public function __invoke(ContainerInterface $container, $requestedName, array $options = null)
{
$pm = $container->get(ToolCollector::class);
return new $requestedName($pm);
}
}
// Next is not reachable, And I do not know why...
class ToolFactory implements FactoryInterface
{
public function __invoke(ContainerInterface $container, $requestedName, array $options = null)
{
$pm = $container->get(ToolCollector::class);
return new $requestedName($pm);
}
}
In module.config.php
return [
...
'service_manager' => [
'aliases' => [
ToolCollectorInterface::class => ToolCollector::class,
],
'factories' => [
Service\ToolCollector::class => InvokableFactory::class,
],
],
'controllers' => [
'factories' => [
Controller\App\SomeController ::class => ToolControllerFactory::class,
]
],
...
];
Is it possible to do it?
How to write factory to make it possilbe?

Answer 1

You must understand something very easy to spot using IoC Inversion of Control. The Container is handling the building process and a reference to the instances you need.
So it is cumbersome and useless, in fact, to make a new inside your indexAction().
You should (and, in fact, you must do it to follow best practices) make any new inside your factory for each dependency your SomeController has.
So you will have many factories. For your Controllers, for your Services, for your Repositories, etc. Each factory has its own logic to build the object you need.
If there is no deps, you can use the default InvokableFactory factory without to write yours. If there is at least one dep, then you must write your own factory with returning your Controller / Service / Repository / etc. class which is built as a ready to use object instance.
The code :
class ToolFactory implements FactoryInterface
{
public function __invoke(ContainerInterface $container, $requestedName, array $options = null)
{
$pm = $container->get(ToolCollector::class);
return new $requestedName($pm);
}
}
I do not see any ToolFactory inside your config, only a ToolControllerFactory :
'controllers' => [
'factories' => [
Controller\App\SomeController ::class => ToolControllerFactory::class,
]
],
So it is normal that is sending you a http 500 error, because it does not know the factory your are trying to use to build your Controller.
Zend Framework / Laminas is very tied to configuration. You must follow principles and then you can build your own path to make the things work. But, much important thing, you must be structured enough to not lose yourself in the forest.
Go step by step without the will to change the world when you are starting to walk. Dreams are necessary. But you have to handle a learning curve firstly, as any of us !