ISSUE-278:

- Added possibility for auto-wire monolog channels according to variable type-hint and name.
  Variable will have appropriated name to camel cased monolog channel service name: `monolog.logger.acme -> $monologLoggerAcme`.
- Removed useless import `DefinitionDecorator`.

Author: adrenalinkin

DependencyInjection/Compiler/LoggerChannelPass.php

@@ -11,13 +11,13 @@
 
 namespace Symfony\Bundle\MonologBundle\DependencyInjection\Compiler;
 
+use Psr\Log\LoggerInterface;
 use Symfony\Component\DependencyInjection\Argument\BoundArgument;
-use Symfony\Component\DependencyInjection\Reference;
 use Symfony\Component\DependencyInjection\ChildDefinition;
-use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
-use Symfony\Component\DependencyInjection\DefinitionDecorator;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Exception\InvalidArgumentException;
+use Symfony\Component\DependencyInjection\Reference;
 
 /**
  * Replaces the default logger by another one with its own channel for tagged services.
@@ -28,6 +28,9 @@ class LoggerChannelPass implements CompilerPassInterface
 {
     protected $channels = array('app');
 
+    /**
+     * {@inheritDoc}
+     */
     public function process(ContainerBuilder $container)
     {
         if (!$container->hasDefinition('monolog.logger')) {
@@ -105,11 +108,19 @@ public function process(ContainerBuilder $container)
         }
     }
 
+    /**
+     * @return array
+     */
     public function getChannels()
     {
         return $this->channels;
     }
 
+    /**
+     * @param array $configuration
+     *
+     * @return array
+     */
     protected function processChannels($configuration)
     {
         if (null === $configuration) {
@@ -123,6 +134,13 @@ protected function processChannels($configuration)
         return array_diff($this->channels, $configuration['elements']);
     }
 
+    /**
+     * Create new logger from th monolog.logger_prototype
+     *
+     * @param string $channel
+     * @param string $loggerId
+     * @param ContainerBuilder $container
+     */
     protected function createLogger($channel, $loggerId, ContainerBuilder $container)
     {
         if (!in_array($channel, $this->channels)) {
@@ -131,6 +149,11 @@ protected function createLogger($channel, $loggerId, ContainerBuilder $container
             $container->setDefinition($loggerId, $logger);
             $this->channels[] = $channel;
         }
+
+        // Allows only for Symfony 4.2+
+        if (\method_exists($container, 'registerAliasForArgument')) {
+            $container->registerAliasForArgument($loggerId, LoggerInterface::class);
+        }
     }
 
     /**

Tests/DependencyInjection/Compiler/LoggerChannelPassTest.php

@@ -13,12 +13,12 @@
 
 use PHPUnit\Framework\TestCase;
 use Psr\Log\LoggerInterface;
-use Symfony\Component\DependencyInjection\Reference;
-use Symfony\Component\DependencyInjection\Definition;
-use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Bundle\MonologBundle\DependencyInjection\Compiler\LoggerChannelPass;
 use Symfony\Component\Config\FileLocator;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Definition;
 use Symfony\Component\DependencyInjection\Loader\XmlFileLoader;
+use Symfony\Component\DependencyInjection\Reference;
 
 class LoggerChannelPassTest extends TestCase
 {
@@ -51,7 +51,19 @@ public function testProcess()
             }
         }
 
-        $this->assertNotNull($container->getDefinition('monolog.logger.manualchan'));
+        $this->assertNotNull($container->getDefinition('monolog.logger.additional'));
+
+        if (!\method_exists(ContainerBuilder::class, 'registerAliasForArgument')) {
+            return;
+        }
+
+        $expectedChannels = \array_keys($expected);
+        $expectedChannels[] = 'additional';
+
+        foreach ($expectedChannels as $channelName) {
+            $aliasName = LoggerInterface::class.' $monologLogger'.\ucfirst($channelName);
+            $this->assertTrue($container->hasAlias($aliasName), 'type-hinted alias should be exists for each logger channel');
+        }
     }
 
     public function testProcessSetters()
@@ -166,7 +178,7 @@ private function getContainer()
             $container->setDefinition($name, $service);
         }
 
-        $container->setParameter('monolog.additional_channels', array('manualchan'));
+        $container->setParameter('monolog.additional_channels', array('additional'));
         $container->setParameter('monolog.handlers_to_channels', array(
             'monolog.handler.a' => array(
                 'type' => 'inclusive',
@@ -202,7 +214,7 @@ private function getContainerWithSetter()
         $service->addMethodCall('setLogger', array(new Reference('logger')));
         $container->setDefinition('foo', $service);
 
-        $container->setParameter('monolog.additional_channels', array('manualchan'));
+        $container->setParameter('monolog.additional_channels', array('additional'));
         $container->setParameter('monolog.handlers_to_channels', array());
 
         $container->getCompilerPassConfig()->setOptimizationPasses(array());