fix: add buffer flusher for sentry handler

Author: Litarnus

src/DependencyInjection/Compiler/SentryBufferFlushPass.php

@@ -0,0 +1,70 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Sentry\SentryBundle\DependencyInjection\Compiler;
+
+use Monolog\Handler\BufferHandler;
+use Sentry\Monolog\Handler as SentryHandler;
+use Sentry\SentryBundle\EventListener\SentryBufferFlusher;
+use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Definition;
+use Symfony\Component\DependencyInjection\Reference;
+
+class SentryBufferFlushPass implements CompilerPassInterface
+{
+    public function process(ContainerBuilder $container): void
+    {
+        $sentryBufferHandlers = $this->findSentryBufferHandlers($container);
+
+        if (empty($sentryBufferHandlers)) {
+            return;
+        }
+
+        $flusherDefinition = new Definition(SentryBufferFlusher::class);
+        $flusherDefinition->setArguments([$sentryBufferHandlers]);
+        $flusherDefinition->addTag('kernel.event_subscriber');
+
+        $container->setDefinition('sentry.buffer_flusher', $flusherDefinition);
+    }
+
+    /**
+     * Finds all {@link BufferHandler} that wrap {@link SentryHandler} and register a service
+     * that will flush them on KernelEvents::TERMINATE to make sure that all events retain
+     * breadcrumbs and context information.
+     *
+     * @return Reference[]
+     */
+    private function findSentryBufferHandlers(ContainerBuilder $container): array
+    {
+        $sentryBufferHandlers = [];
+
+        foreach ($container->getDefinitions() as $serviceId => $definition) {
+            if (BufferHandler::class === $definition->getClass()) {
+                $arguments = $definition->getArguments();
+                if (!empty($arguments)) {
+                    // The first argument of BufferHandler is the HandlerInterface, which
+                    // can be a SentryHandler.
+                    $firstArgument = $arguments[0];
+
+                    if ($firstArgument instanceof Reference) {
+                        $referencedServiceId = (string) $firstArgument;
+                        try {
+                            $referencedDefinition = $container->findDefinition($referencedServiceId);
+
+                            if (SentryHandler::class === $referencedDefinition->getClass()) {
+                                $sentryBufferHandlers[] = new Reference($serviceId);
+                            }
+                        } catch (\Exception $e) {
+                            // If the service from the first argument doesn't exist we just keep going
+                            continue;
+                        }
+                    }
+                }
+            }
+        }
+
+        return $sentryBufferHandlers;
+    }
+}

src/EventListener/SentryBufferFlusher.php

@@ -0,0 +1,53 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Sentry\SentryBundle\EventListener;
+
+use Monolog\Handler\BufferHandler;
+use Symfony\Component\Console\ConsoleEvents;
+use Symfony\Component\Console\Event\ConsoleTerminateEvent;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+use Symfony\Component\HttpKernel\Event\TerminateEvent;
+use Symfony\Component\HttpKernel\KernelEvents;
+
+class SentryBufferFlusher implements EventSubscriberInterface
+{
+    /**
+     * @var BufferHandler[]
+     */
+    private $bufferHandlers;
+
+    /**
+     * @param BufferHandler[] $bufferHandlers
+     */
+    public function __construct(array $bufferHandlers = [])
+    {
+        $this->bufferHandlers = $bufferHandlers;
+    }
+
+    public static function getSubscribedEvents(): array
+    {
+        return [
+            KernelEvents::TERMINATE => ['onKernelTerminate', 10],
+            ConsoleEvents::TERMINATE => ['onConsoleTerminate', 10],
+        ];
+    }
+
+    public function onKernelTerminate(TerminateEvent $event): void
+    {
+        $this->flushBuffers();
+    }
+
+    public function onConsoleTerminate(ConsoleTerminateEvent $event): void
+    {
+        $this->flushBuffers();
+    }
+
+    private function flushBuffers(): void
+    {
+        foreach ($this->bufferHandlers as $handler) {
+            $handler->flush();
+        }
+    }
+}

src/SentryBundle.php

@@ -8,6 +8,7 @@
 use Sentry\SentryBundle\DependencyInjection\Compiler\CacheTracingPass;
 use Sentry\SentryBundle\DependencyInjection\Compiler\DbalTracingPass;
 use Sentry\SentryBundle\DependencyInjection\Compiler\HttpClientTracingPass;
+use Sentry\SentryBundle\DependencyInjection\Compiler\SentryBufferFlushPass;
 use Symfony\Component\DependencyInjection\Compiler\PassConfig;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\HttpKernel\Bundle\Bundle;
@@ -26,5 +27,6 @@ public function build(ContainerBuilder $container): void
         $container->addCompilerPass(new CacheTracingPass());
         $container->addCompilerPass(new HttpClientTracingPass());
         $container->addCompilerPass(new AddLoginListenerTagPass());
+        $container->addCompilerPass(new SentryBufferFlushPass());
     }
 }