PHP Symfony request stack not found on bundle extension load - php

Question

I'm trying to create reusable logging bundle which can have custom formatter for log messages.
Formatter is set in the main app's config file like that:
custom_logger:
formatter: AppBundle\Services\MessageFormatter
Then in the LoggerBundle/DependencyInjection/CustomLoggerExtension.php
after i receive this configuration i'm trying to get logger service and set formatter
class CustomLoggerExtension extends ConfigurableExtension
{
public function loadInternal(array $mergedConfig, ContainerBuilder $container)
{
$loader = new YamlFileLoader($container, new FileLocator(__DIR__ . '/../Resources/config'));
$loader->load('services.yml');
$class = $mergedConfig['formatter'];
$obj = new $class;
$container->get('custom.logger')->setFormatter($obj);
but the problem is that logger uses request stack
services:
custom.logger:
class: LoggerBundle\Services\Logger
arguments: ['#request_stack']
and so when i try to get service in loadInternal function it seems that the request stack is not initialized yet and i receive error: You have requested a non-existent service "request_stack"
What is the correct way of doing this?
EDIT (2016-04-21 21:54:11)
That's weird. Even if i remove request stack and successfully set formatter in loadInternal, it's not in the service when i'm getting it from the controller in main app.
I must be doing something really wrong :)

Answer 1

Ok, I think I figured it out.
When load() or as in my case loadInternal() method is called, symfony passes there completely new container which is then merged into the main one.
So if I request a service and it is created there, it's not saved anywhere but in the temporary container and is eventually destroyed (only service definitions are passed to the main one).
Since services are loaded(created) on demand, it's not right to instantiate it on bundle load.
So what you want to do instead is to configure definitions
Here is how I got it working:
use Symfony\Component\HttpKernel\DependencyInjection\ConfigurableExtension;
use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
use Symfony\Component\DependencyInjection\ContainerBuilder;
use Symfony\Component\DependencyInjection\Loader\YamlFileLoader;
use Symfony\Component\DependencyInjection\Reference;
use Symfony\Component\DependencyInjection\Definition;
use Symfony\Component\Config\FileLocator;
use LoggerBundle\Formatter\MessageFormatterInterface;
class LoggerBundleExtension extends ConfigurableExtension implements CompilerPassInterface
{
protected $customFormatter;
public function loadInternal(array $mergedConfig, ContainerBuilder $container)
{
$loader = new YamlFileLoader($container, new FileLocator(__DIR__ . '/../Resources/config'));
$loader->load('services.yml');
if (array_key_exists('formatter', $mergedConfig)) {
$this->customFormatter = $mergedConfig['formatter'];
}
}
public function process(ContainerBuilder $containerBuilder)
{
if ($this->customFormatter) {
$class = $this->customFormatter;
//if formatter is service id
$serviceUsed = $containerBuilder->has($this->customFormatter);
if ($serviceUsed) {
$class = $containerBuilder->getDefinition($this->customFormatter)->getClass();
}
if (!class_exists($class) || !is_a($class, MessageFormatterInterface::class, true)) {
throw new \ErrorException('Invalid logger formatter');
}
if ($serviceUsed) {
$containerBuilder
->getDefinition('custom.logger')
->addMethodCall('setFormatter', array(new Reference($this->customFormatter)));
} else {
$containerBuilder
->getDefinition('custom.logger')
->addMethodCall('setFormatter', array(new Definition($this->customFormatter)));
}
}
}
}
In loadInternal() I check if formatter is set in main app's config and save it.
But main thing is happening in process() function (you have to implement Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface for it to run).
From the docs.
As process() is called after all extensions are loaded, it allows you to edit service definitions of other extensions as well as retrieving information about service definitions.
So, what I am doing is:
checking if formatter option value is a class name or a service id(if that's the case, I retrieve class name from service definition)
validate class name (checking if it's a valid class and making sure it implements required interface)
adding definition to my logger service which tells container to call setFormatter with provided arguments when logger service is created(when it is first retrieved from the container)
Basically
$containerBuilder->getDefinition('custom.logger')->addMethodCall('setFormatter', array(new Reference('my_formatter')));
is the same as declaring in your config:
services:
custom.logger:
class: LoggerBundle\Services\Logger
arguments: ['#request_stack']
calls:
- [setFormatter, ['#my_formatter']]