Symfony将所有捆绑软件参数注入DI服务

Question

I am using Symfony and trying to create a service that holds all of the application parameters that we have set in our parameters.xml in our AppBundle.

I did it last time by injecting the ServiceContainer into the Service and using ->get('param_name') on it which worked fine though I know that it is quite bad practice to inject the whole container.

Is there a way I can just get all parameters injected into my service without having to add them each as an arg to the service definition??

Last project I did this in essence

Service Definition

<service id="myapp.application_parameters" class="AppBundle\DependencyInjection\Service\ApplicationParametersService">
    <argument type="service" id="service_container" />
</service>

And service class

namespace AppBundle\DependencyInjection\Service;

use Symfony\Component\DependencyInjection\ContainerInterface;

class ApplicationParametersService
{
    private $_container;
    protected $developmentEmail;

    function __construct(ContainerInterface $container)
    {
        $this->_container = $container;

        $this->developmentEmail = $this->_container->getParameter('myapp.dev.email');

    }

public function getDevEmail()
{
    return $this->developmentEmail;
}

Answer 1

You are right: injection of container is antipattern in most cases. But injection of all parameters is a bad practice too: you don't know exactly what parameters are actually used by the service, because it has access to all of them. It is better when the code gets only the values that it really needs.

If this way is acceptable and you need to just reduce a boilerplate code, then you can use a parent service or the autowiring.

1) With parent service :

<service id="generic_service" abstract="true">
    <!-- it's better than whole container -->
    <argument type="service" id="myapp.application_parameters"/>
</service>

<service id="specific_service_a" class="..." parent="generic_service"/>
<service id="specific_service_b" class="..." parent="generic_service"/>

2) With autowiring:

<service id="specific_service_a" class="..." autowire="true">

At least you can get the container through a global variable . Most risky way, but it works.