symfony · GromNaN · Oct 19, 2025 · Oct 2, 2025
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -16,6 +16,7 @@
 * Fix `host` configuration for `elastic_search` handler
 * Add `hosts` configuration for `elastica` handler
 * Add `enabled` option to `handlers` configuration
+* Add `priority` field to `processor` tag
 
 ## 3.10.0 (2023-11-06)
 

diff --git a/config/monolog.php b/config/monolog.php
@@ -38,6 +38,7 @@
             ->parent('monolog.logger_prototype')
             ->args(['index_0' => 'app'])
             ->call('useMicrosecondTimestamps', [param('monolog.use_microseconds')])
+            ->tag('monolog.channel_logger')
 
         ->set('monolog.logger_prototype', Logger::class)
             ->args([abstract_arg('channel')])

diff --git a/src/DependencyInjection/Compiler/AddProcessorsPass.php b/src/DependencyInjection/Compiler/AddProcessorsPass.php
@@ -11,10 +11,11 @@
 
 namespace Symfony\Bundle\MonologBundle\DependencyInjection\Compiler;
 
+use Symfony\Component\DependencyInjection\Argument\TaggedIteratorArgument;
 use Symfony\Component\DependencyInjection\ChildDefinition;
 use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
+use Symfony\Component\DependencyInjection\Compiler\PriorityTaggedServiceTrait;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
-use Symfony\Component\DependencyInjection\Reference;
 
 /**
  * Registers processors in Monolog loggers or handlers.
@@ -25,48 +26,68 @@
  */
 class AddProcessorsPass implements CompilerPassInterface
 {
+    use PriorityTaggedServiceTrait;
+
     public function process(ContainerBuilder $container)
     {
         if (!$container->hasDefinition('monolog.logger')) {
             return;
         }
 
+        $indexedTags = [];
+        $i = 1;
+
         foreach ($container->findTaggedServiceIds('monolog.processor') as $id => $tags) {
             if (array_any($tags, $closure = function (array $tag) { return (bool) $tag; })) {
                 $tags = array_filter($tags, $closure);
             }
 
-            foreach ($tags as $tag) {
-                if (!empty($tag['channel']) && !empty($tag['handler'])) {
-                    throw new \InvalidArgumentException(\sprintf('you cannot specify both the "handler" and "channel" attributes for the "monolog.processor" tag on service "%s".', $id));
-                }
+            foreach ($tags as &$tag) {
+                $indexedTags[$tag['index'] = $i++] = $tag;
+            }
+            unset($tag);
+            $definition = $container->getDefinition($id);
+            $definition->setTags(array_merge($definition->getTags(), ['monolog.processor' => $tags]));
+        }
 
-                if (!empty($tag['handler'])) {
-                    $definition = $container->findDefinition(\sprintf('monolog.handler.%s', $tag['handler']));
-                    $parentDef = $definition;
-                    while (!$parentDef->getClass() && $parentDef instanceof ChildDefinition) {
-                        $parentDef = $container->findDefinition($parentDef->getParent());
-                    }
-                    $class = $container->getParameterBag()->resolveValue($parentDef->getClass());
-                    if (!method_exists($class, 'pushProcessor')) {
-                        throw new \InvalidArgumentException(\sprintf('The "%s" handler does not accept processors.', $tag['handler']));
-                    }
-                } elseif (!empty($tag['channel'])) {
-                    if ('app' === $tag['channel']) {
-                        $definition = $container->getDefinition('monolog.logger');
-                    } else {
-                        $definition = $container->getDefinition(\sprintf('monolog.logger.%s', $tag['channel']));
-                    }
-                } else {
-                    $definition = $container->getDefinition('monolog.logger_prototype');
-                }
+        $taggedIteratorArgument = new TaggedIteratorArgument('monolog.processor', 'index', null, true);
+        // array_reverse is used because ProcessableHandlerTrait::pushProcessor prepends processors to the beginning of the stack
+        foreach (array_reverse($this->findAndSortTaggedServices($taggedIteratorArgument, $container), true) as $index => $reference) {
+            $tag = $indexedTags[$index];
 
-                if (!empty($tag['method'])) {
-                    $processor = [new Reference($id), $tag['method']];
-                } else {
-                    // If no method is defined, fallback to use __invoke
-                    $processor = new Reference($id);
+            if (!empty($tag['channel']) && !empty($tag['handler'])) {
+                throw new \InvalidArgumentException(\sprintf('You cannot specify both the "handler" and "channel" attributes for the "monolog.processor" tag on service "%s".', $reference));
+            }
+
+            if (!empty($tag['handler'])) {
+                $parentDef = $container->findDefinition(\sprintf('monolog.handler.%s', $tag['handler']));
+                $definitions = [$parentDef];
+                while (!$parentDef->getClass() && $parentDef instanceof ChildDefinition) {
+                    $parentDef = $container->findDefinition($parentDef->getParent());
+                }
+                $class = $container->getParameterBag()->resolveValue($parentDef->getClass());
+                if (!method_exists($class, 'pushProcessor')) {
+                    throw new \InvalidArgumentException(\sprintf('The "%s" handler does not accept processors.', $tag['handler']));
+                }
+            } elseif (!empty($tag['channel'])) {
+                $loggerId = 'app' === $tag['channel'] ? 'monolog.logger' : \sprintf('monolog.logger.%s', $tag['channel']);
+                $definitions = [$container->getDefinition($loggerId)];
+            } elseif ($loggerIds = $container->findTaggedServiceIds('monolog.channel_logger')) {
+                $definitions = [];
+                foreach ($loggerIds as $loggerId => $tags) {
+                    $definitions[] = $container->getDefinition($loggerId);
                 }
+            } else {
+                $definitions = [$container->getDefinition('monolog.logger_prototype')];
+            }
+
+            if (!empty($tag['method'])) {
+                $processor = [$reference, $tag['method']];
+            } else {
+                // If no method is defined, fallback to use __invoke
+                $processor = $reference;
+            }
+            foreach ($definitions as $definition) {
                 $definition->addMethodCall('pushProcessor', [$processor]);
             }
         }

diff --git a/src/DependencyInjection/Compiler/LoggerChannelPass.php b/src/DependencyInjection/Compiler/LoggerChannelPass.php
@@ -138,6 +138,7 @@ protected function createLogger(string $channel, string $loggerId, ContainerBuil
         if (!\in_array($channel, $this->channels)) {
             $logger = new ChildDefinition('monolog.logger_prototype');
             $logger->replaceArgument(0, $channel);
+            $logger->addTag('monolog.channel_logger');
             $container->setDefinition($loggerId, $logger);
             $this->channels[] = $channel;
         }

diff --git a/tests/DependencyInjection/Compiler/AddProcessorsPassTest.php b/tests/DependencyInjection/Compiler/AddProcessorsPassTest.php
@@ -24,6 +24,7 @@
 use Symfony\Component\DependencyInjection\Definition;
 use Symfony\Component\DependencyInjection\Loader\PhpFileLoader;
 use Symfony\Component\DependencyInjection\Reference;
+use Symfony\Component\DependencyInjection\TypedReference;
 
 class AddProcessorsPassTest extends TestCase
 {
@@ -34,12 +35,40 @@ public function testHandlerProcessors()
         $service = $container->getDefinition('monolog.handler.test');
         $calls = $service->getMethodCalls();
         $this->assertCount(1, $calls);
-        $this->assertEquals(['pushProcessor', [new Reference('test')]], $calls[0]);
+        $this->assertEquals(['pushProcessor', [new TypedReference('test', 'TestClass')]], $calls[0]);
 
         $service = $container->getDefinition('handler_test');
         $calls = $service->getMethodCalls();
         $this->assertCount(1, $calls);
-        $this->assertEquals(['pushProcessor', [new Reference('test2')]], $calls[0]);
+        $this->assertEquals(['pushProcessor', [new TypedReference('test2', 'TestClass')]], $calls[0]);
+
+        $service = $container->getDefinition('monolog.handler.priority_test');
+        $calls = $service->getMethodCalls();
+        $this->assertCount(5, $calls);
+        $this->assertEquals(['pushProcessor', [new TypedReference('processor-10', 'TestClass')]], $calls[0]);
+        $this->assertEquals(['pushProcessor', [new TypedReference('processor+10', 'TestClass')]], $calls[1]);
+        $this->assertEquals(['pushProcessor', [new TypedReference('processor+20', 'TestClass')]], $calls[2]);
+        $this->assertEquals(['pushProcessor', [new TypedReference('processor+20', 'TestClass')]], $calls[2]);
+        $this->assertEquals(['pushProcessor', [new TypedReference('processor+25+35', 'TestClass')]], $calls[3]);
+        $this->assertEquals(['pushProcessor', [new TypedReference('processor+35+25', 'TestClass')]], $calls[4]);
+
+        $service = $container->getDefinition('monolog.handler.priority_test_2');
+        $calls = $service->getMethodCalls();
+        $this->assertCount(2, $calls);
+        $this->assertEquals(['pushProcessor', [new TypedReference('processor+35+25', 'TestClass')]], $calls[0]);
+        $this->assertEquals(['pushProcessor', [new TypedReference('processor+25+35', 'TestClass')]], $calls[1]);
+
+        $service = $container->getDefinition('monolog.logger');
+        $calls = $service->getMethodCalls();
+        $this->assertCount(2, $calls);
+        $this->assertEquals(['useMicrosecondTimestamps', ['%monolog.use_microseconds%']], $calls[0]);
+        $this->assertEquals(['pushProcessor', [new TypedReference('processor_all_channels+0', 'TestClass')]], $calls[1]);
+
+        $service = $container->getDefinition('monolog.logger.test');
+        $calls = $service->getMethodCalls();
+        $this->assertCount(2, $calls);
+        $this->assertEquals(['pushProcessor', [new TypedReference('processor_test_channel-25', 'TestClass')]], $calls[0]);
+        $this->assertEquals(['pushProcessor', [new TypedReference('processor_all_channels+0', 'TestClass')]], $calls[1]);
     }
 
     public function testFailureOnHandlerWithoutPushProcessor()
@@ -97,7 +126,7 @@ public static function provideEmptyTagsData(): iterable
     {
         yield 'with empty tag' => [
             [[]],
-            [['pushProcessor', [new Reference('TestClass')]], ['useMicrosecondTimestamps', ['%monolog.use_microseconds%']]],
+            [['useMicrosecondTimestamps', ['%monolog.use_microseconds%']], ['pushProcessor', [new Reference('TestClass')]]],
             [['pushProcessor', [new Reference('TestClass')]]],
         ];
 
@@ -115,7 +144,7 @@ public static function provideEmptyTagsData(): iterable
 
         yield 'with method and no channel' => [
             [[], ['method' => 'foo']],
-            [['pushProcessor', [[new Reference('TestClass'), 'foo']]], ['useMicrosecondTimestamps', ['%monolog.use_microseconds%']]],
+            [['useMicrosecondTimestamps', ['%monolog.use_microseconds%']], ['pushProcessor', [[new Reference('TestClass'), 'foo']]]],
             [['pushProcessor', [[new Reference('TestClass'), 'foo']]]],
         ];
     }
@@ -126,24 +155,62 @@ protected function getContainer()
         $loader = new PhpFileLoader($container, new FileLocator(__DIR__.'/../../../config'));
         $loader->load('monolog.php');
 
+        $container->setParameter('monolog.additional_channels', ['test']);
+        $container->setParameter('monolog.handlers_to_channels', []);
+
         $definition = $container->getDefinition('monolog.logger_prototype');
         $container->setParameter('monolog.handler.console.class', ConsoleHandler::class);
         $container->setDefinition('monolog.handler.test', new Definition('%monolog.handler.console.class%', [100, false]));
         $container->setDefinition('handler_test', new Definition('%monolog.handler.console.class%', [100, false]));
+        $container->setDefinition('monolog.handler.priority_test', new Definition('%monolog.handler.console.class%', [100, false]));
+        $container->setDefinition('monolog.handler.priority_test_2', new Definition('%monolog.handler.console.class%', [100, false]));
         $container->setAlias('monolog.handler.test2', 'handler_test');
         $definition->addMethodCall('pushHandler', [new Reference('monolog.handler.test')]);
         $definition->addMethodCall('pushHandler', [new Reference('monolog.handler.test2')]);
+        $definition->addMethodCall('pushHandler', [new Reference('monolog.handler.priority_test')]);
+        $definition->addMethodCall('pushHandler', [new Reference('monolog.handler.priority_test_2')]);
 
-        $service = new Definition('TestClass', ['false', new Reference('logger')]);
+        $service = new Definition('TestClass');
         $service->addTag('monolog.processor', ['handler' => 'test']);
         $container->setDefinition('test', $service);
 
-        $service = new Definition('TestClass', ['false', new Reference('logger')]);
+        $service = new Definition('TestClass');
         $service->addTag('monolog.processor', ['handler' => 'test2']);
         $container->setDefinition('test2', $service);
 
+        $service = new Definition('TestClass');
+        $service->addTag('monolog.processor', ['handler' => 'priority_test', 'priority' => 10]);
+        $container->setDefinition('processor+10', $service);
+
+        $service = new Definition('TestClass');
+        $service->addTag('monolog.processor', ['handler' => 'priority_test', 'priority' => -10]);
+        $container->setDefinition('processor-10', $service);
+
+        $service = new Definition('TestClass');
+        $service->addTag('monolog.processor', ['handler' => 'priority_test', 'priority' => 20]);
+        $container->setDefinition('processor+20', $service);
+
+        $service = new Definition('TestClass');
+        $service->addTag('monolog.processor', ['handler' => 'priority_test', 'priority' => 35]);
+        $service->addTag('monolog.processor', ['handler' => 'priority_test_2', 'priority' => 25]);
+        $container->setDefinition('processor+35+25', $service);
+
+        $service = new Definition('TestClass');
+        $service->addTag('monolog.processor', ['handler' => 'priority_test', 'priority' => 25]);
+        $service->addTag('monolog.processor', ['handler' => 'priority_test_2', 'priority' => 35]);
+        $container->setDefinition('processor+25+35', $service);
+
+        $service = new Definition('TestClass');
+        $service->addTag('monolog.processor', ['priority' => 0]);
+        $container->setDefinition('processor_all_channels+0', $service);
+
+        $service = new Definition('TestClass');
+        $service->addTag('monolog.processor', ['channel' => 'test', 'priority' => -25]);
+        $container->setDefinition('processor_test_channel-25', $service);
+
         $container->getCompilerPassConfig()->setOptimizationPasses([]);
         $container->getCompilerPassConfig()->setRemovingPasses([]);
+        $container->addCompilerPass(new LoggerChannelPass());
         $container->addCompilerPass(new AddProcessorsPass());
         $container->compile();