[12.x] Introduce ContextLogProcessor (#54851)

* introduce setContextToLogProcessor

* rename

* tests

* tests

* tests

* add context log processor

* use processor

* return type

* removes unnecessary import

* Update ContextTest.php

* add interface to contracts

* formatting

* Update ContextServiceProvider.php

---------

Co-authored-by: Taylor Otwell <taylor@laravel.com>

Author: cosmastech

src/Illuminate/Contracts/Log/ContextLogProcessor.php

@@ -0,0 +1,9 @@
+<?php
+
+namespace Illuminate\Contracts\Log;
+
+use Monolog\Processor\ProcessorInterface;
+
+interface ContextLogProcessor extends ProcessorInterface
+{
+}

src/Illuminate/Log/Context/ContextLogProcessor.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace Illuminate\Log\Context;
+
+use Illuminate\Contracts\Foundation\Application;
+use Illuminate\Contracts\Log\ContextLogProcessor as ContextLogProcessorContract;
+use Illuminate\Log\Context\Repository as ContextRepository;
+use Monolog\LogRecord;
+
+class ContextLogProcessor implements ContextLogProcessorContract
+{
+    /**
+     * Create a new ContextLogProcessor instance.
+     *
+     * @param  \Illuminate\Contracts\Foundation\Application  $app
+     * @return void
+     */
+    public function __construct(protected Application $app)
+    {
+    }
+
+    /**
+     * Add contextual data to the log's "extra" parameter.
+     *
+     * @param  \Monolog\LogRecord  $record
+     * @return \Monolog\LogRecord
+     */
+    public function __invoke(LogRecord $record): LogRecord
+    {
+        if (! $this->app->bound(ContextRepository::class)) {
+            return $record;
+        }
+
+        return $record->with(extra: [
+            ...$record->extra,
+            ...$this->app[ContextRepository::class]->all(),
+        ]);
+    }
+}

src/Illuminate/Log/Context/ContextServiceProvider.php

@@ -2,6 +2,7 @@
 
 namespace Illuminate\Log\Context;
 
+use Illuminate\Contracts\Log\ContextLogProcessor as ContextLogProcessorContract;
 use Illuminate\Queue\Events\JobProcessing;
 use Illuminate\Queue\Queue;
 use Illuminate\Support\Facades\Context;
@@ -17,6 +18,8 @@ class ContextServiceProvider extends ServiceProvider
     public function register()
     {
         $this->app->scoped(Repository::class);
+
+        $this->app->bind(ContextLogProcessorContract::class, fn ($app) => new ContextLogProcessor($app));
     }
 
     /**

src/Illuminate/Log/LogManager.php

@@ -3,7 +3,7 @@
 namespace Illuminate\Log;
 
 use Closure;
-use Illuminate\Log\Context\Repository as ContextRepository;
+use Illuminate\Contracts\Log\ContextLogProcessor;
 use Illuminate\Support\Collection;
 use Illuminate\Support\Str;
 use InvalidArgumentException;
@@ -143,16 +143,7 @@ protected function get($name, ?array $config = null)
                 )->withContext($this->sharedContext);
 
                 if (method_exists($loggerWithContext->getLogger(), 'pushProcessor')) {
-                    $loggerWithContext->pushProcessor(function ($record) {
-                        if (! $this->app->bound(ContextRepository::class)) {
-                            return $record;
-                        }
-
-                        return $record->with(extra: [
-                            ...$record->extra,
-                            ...$this->app[ContextRepository::class]->all(),
-                        ]);
-                    });
+                    $loggerWithContext->pushProcessor($this->app->make(ContextLogProcessor::class));
                 }
 
                 return $this->channels[$name] = $loggerWithContext;

tests/Log/ContextTest.php

@@ -4,6 +4,7 @@
 
 use Exception;
 use Illuminate\Contracts\Debug\ExceptionHandler;
+use Illuminate\Contracts\Log\ContextLogProcessor;
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Foundation\Testing\LazilyRefreshDatabase;
 use Illuminate\Log\Context\Events\ContextDehydrating as Dehydrating;
@@ -13,13 +14,21 @@
 use Illuminate\Support\Facades\Event;
 use Illuminate\Support\Facades\Log;
 use Illuminate\Support\Str;
+use Monolog\LogRecord;
 use Orchestra\Testbench\TestCase;
 use RuntimeException;
 
 class ContextTest extends TestCase
 {
     use LazilyRefreshDatabase;
 
+    #[\Override]
+    protected function tearDown(): void
+    {
+        parent::tearDown();
+        MyAddContextProcessor::$wasConstructed = false;
+    }
+
     public function test_it_can_set_values()
     {
         $values = [
@@ -544,6 +553,55 @@ public function test_scope_sets_keys_and_restores()
             'hiddenKey2' => 'world',
         ], Context::allHidden());
     }
+
+    public function test_uses_closure_for_context_processor()
+    {
+        $path = storage_path('logs/laravel.log');
+        file_put_contents($path, '');
+
+        $this->app->bind(
+            ContextLogProcessor::class,
+            fn () => function (LogRecord $record): LogRecord {
+                $logChannel = Context::getHidden('log_channel_name');
+
+                return $record->with(
+                    // allow overriding the context from what's been set on the log
+                    context: array_merge(Context::all(), $record->context),
+                    // use the log channel we've set in context, or fallback to the current channel
+                    channel: $logChannel ?? $record->channel,
+                );
+            }
+        );
+
+        Context::addHidden('log_channel_name', 'closure-test');
+        Context::add(['value_from_context' => 'hello']);
+
+        Log::info('This is an info log.', ['value_from_log_info_context' => 'foo']);
+
+        $log = Str::after(file_get_contents($path), '] ');
+        $this->assertSame('closure-test.INFO: This is an info log. {"value_from_context":"hello","value_from_log_info_context":"foo"}', Str::trim($log));
+        file_put_contents($path, '');
+    }
+
+    public function test_can_rebind_to_separate_class()
+    {
+        $path = storage_path('logs/laravel.log');
+        file_put_contents($path, '');
+
+        $this->app->bind(ContextLogProcessor::class, MyAddContextProcessor::class);
+
+        Context::add(['this-will-be-included' => false]);
+
+        Log::info('This is an info log.', ['value_from_log_info_context' => 'foo']);
+        $log = Str::after(file_get_contents($path), '] ');
+        $this->assertSame(
+            'testing.INFO: This is an info log. {"value_from_log_info_context":"foo","inside of MyAddContextProcessor":true}',
+            Str::trim($log)
+        );
+        $this->assertTrue(MyAddContextProcessor::$wasConstructed);
+
+        file_put_contents($path, '');
+    }
 }
 
 enum Suit
@@ -566,3 +624,19 @@ class ContextModel extends Model
 {
     //
 }
+
+class MyAddContextProcessor implements ContextLogProcessor
+{
+    public static bool $wasConstructed = false;
+
+    public function __construct()
+    {
+        self::$wasConstructed = true;
+    }
+
+    #[\Override]
+    public function __invoke(LogRecord $record): LogRecord
+    {
+        return $record->with(context: array_merge($record->context, ['inside of MyAddContextProcessor' => true]));
+    }
+}