review fixes

Author: gam6itko

src/Symfony/Component/Mailer/Bridge/Mailjet/Transport/MailjetApiTransport.php

@@ -42,13 +42,13 @@ class MailjetApiTransport extends AbstractApiTransport
         'X-MJ-TemplateErrorReporting' => ['TemplateErrorReporting', 'json'],
         'X-MJ-TemplateErrorDeliver' => ['TemplateErrorDeliver', 'bool'],
         'X-MJ-Vars' => ['Variables', 'json'],
-        'X-MJ-CustomID' => ['CustomID'],
-        'X-MJ-EventPayload' => ['EventPayload'],
-        'X-Mailjet-Campaign' => ['CustomCampaign'],
+        'X-MJ-CustomID' => ['CustomID', 'string'],
+        'X-MJ-EventPayload' => ['EventPayload', 'string'],
+        'X-Mailjet-Campaign' => ['CustomCampaign', 'string'],
         'X-Mailjet-DeduplicateCampaign' => ['DeduplicateCampaign', 'bool'],
         'X-Mailjet-Prio' => ['Priority', 'int'],
-        'X-Mailjet-TrackClick' => ['TrackClick'],
-        'X-Mailjet-TrackOpen' => ['TrackOpen'],
+        'X-Mailjet-TrackClick' => ['TrackClick', 'string'],
+        'X-Mailjet-TrackOpen' => ['TrackOpen', 'string'],
     ];
 
     private string $privateKey;
@@ -139,7 +139,7 @@ private function getPayload(Email $email, Envelope $envelope): array
 
         foreach ($email->getHeaders()->all() as $header) {
             if ($convertConf = self::HEADER_TO_MESSAGE[$header->getName()] ?? false) {
-                $message[$convertConf[0]] = $this->castCustomHeader($header->getBodyAsString(), $convertConf[1] ?? 'string');
+                $message[$convertConf[0]] = $this->castCustomHeader($header->getBodyAsString(), $convertConf[1]);
                 continue;
             }
             if (\in_array($header->getName(), self::FORBIDDEN_HEADERS, true)) {
@@ -200,7 +200,7 @@ private function castCustomHeader(string $value, string $type)
             'bool' => filter_var($value, \FILTER_VALIDATE_BOOLEAN),
             'int' => (int) $value,
             'json' => json_decode($value, true, 2, \JSON_THROW_ON_ERROR),
-            default => $value,
+            'string' => $value,
         };
     }
 }