From b6d5b493cc1763d64f3cd3352f88661a1a5f8c3e Mon Sep 17 00:00:00 2001
From: Nick de Kruijk <git@nickdekruijk.nl>
Date: Thu, 4 Oct 2018 10:47:36 +0200
Subject: [PATCH] Check if output value is valid

---
 src/ResizeController.php | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/ResizeController.php b/src/ResizeController.php
index 9bd3cf1..3507694 100644
--- a/src/ResizeController.php
+++ b/src/ResizeController.php
@@ -145,7 +145,11 @@ private function resize($template, $original, $target)
 
         # Change type to force output format if used in template
         if (isset($template['output'])) {
-            $type = 'image/' . $template['output'];
+            if (in_array($template['output'], ['jpg', 'jpeg', 'png', 'gif'])) {
+                $type = 'image/' . $template['output'];
+            } else {
+                self::error('Invalid output ' . $template['output']);
+            }
         }
 
         # Save the resized image in a variable