feat: error-codes in flash messages to reference log entries

src/Logger/ErrorCodeProcessor.php

@@ -0,0 +1,43 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Logger;
+
+use App\Service\ErrorCodeService;
+use Monolog\Attribute\AsMonologProcessor;
+use Monolog\Level;
+use Monolog\LogRecord;
+
+/**
+ * Adds error reference codes to log records with ERROR level or higher.
+ *
+ * When an error is logged, this processor generates a user-friendly error code
+ * and adds it to the log record's extra data. The code can then be displayed
+ * to users and used by support staff to locate the corresponding log entries.
+ */
+#[AsMonologProcessor]
+class ErrorCodeProcessor
+{
+    public function __construct(
+        private readonly ErrorCodeService $errorCodeService,
+    ) {
+    }
+
+    public function __invoke(LogRecord $record): LogRecord
+    {
+        if ($record->level->value < Level::Error->value) {
+            return $record;
+        }
+
+        $errorCode = $this->errorCodeService->getErrorCode();
+        if (null === $errorCode) {
+            return $record;
+        }
+
+        $this->errorCodeService->markErrorOccurred();
+        $record->extra['error_code'] = $errorCode;
+
+        return $record;
+    }
+}