Fix payload too large error - increase JSON limit and handle base64 data URLs

Author: macayu17

backend/src/server.js

@@ -77,9 +77,9 @@ app.use(cors({
 // Webhook routes need raw body
 app.use('/api/webhooks', express.raw({ type: 'application/json' }));
 
-// Regular JSON parsing for other routes
-app.use(express.json());
-app.use(express.urlencoded({ extended: true }));
+// Regular JSON parsing for other routes - increased limit for certificate data URLs
+app.use(express.json({ limit: '50mb' }));
+app.use(express.urlencoded({ extended: true, limit: '50mb' }));
 app.use(limiter);
 
 // Serve uploaded files

backend/src/services/certificate.service.js

@@ -3,8 +3,21 @@ import fetch from 'node-fetch';
 
 export const generateCertificate = async (templateUrl, mapping, data) => {
   try {
-    // 1. Fetch the template
-    const existingPdfBytes = await fetch(templateUrl).then(res => res.arrayBuffer());
+    // 1. Fetch the template - handle both URLs and base64 data URLs
+    let existingPdfBytes;
+    
+    if (templateUrl.startsWith('data:')) {
+      // Handle base64 data URL
+      const base64Data = templateUrl.split(',')[1];
+      existingPdfBytes = Buffer.from(base64Data, 'base64');
+    } else {
+      // Handle regular URL
+      const response = await fetch(templateUrl);
+      if (!response.ok) {
+        throw new Error(`Failed to fetch template: ${response.status} ${response.statusText}`);
+      }
+      existingPdfBytes = await response.arrayBuffer();
+    }
 
     // 2. Load PDF
     const pdfDoc = await PDFDocument.load(existingPdfBytes);