Add validation for required file parameters in file_server.php

- Added checks for missing file name and file extension.
- Improved error handling with descriptive messages for missing parameters.

services/nginx/app/file_server.php

@@ -18,6 +18,16 @@ if (preg_match('/\.pdf$/', $file)) {
         $isAttachment = true;
     }
 }
+// Require a filename
+if (empty($file)) {
+    echo 'No file specified';
+    exit;
+}
+// Require an extension
+if (!preg_match('/\.[a-zA-Z0-9]+$/', $file)) {
+    echo 'No file extension specified';
+    exit;
+}
 // Check if the file is an attachment
 if (str_contains($file, 'temp_file_')) {
     $isAttachment = true;
@@ -25,10 +35,10 @@ if (str_contains($file, 'temp_file_')) {
 if ($isPDF && $isPDFStore) {
     $file = str_replace('/modules/washcertificates/output/certificates/', '', $file);
 
-// Download the file from minio, and send it to the client
+    // Download the file from minio, and send it to the client
     $wash_certificate_store = new \classes\wash_certificate_store();
 
-// Check if the certificate exists
+    // Check if the certificate exists
     if (!$wash_certificate_store->isFileInStore($file)) {
         // Try the PDF store
         $pdf_store = new \classes\pdf_store();