fix: update NFC payload URL to use environment variable (#417)

Author: roshankumar0036singh

.env.example

@@ -4,6 +4,9 @@ DATABASE_URL=postgresql://devcard:devcard@localhost:5432/devcard?schema=public
 # ─── Redis ───
 REDIS_URL=redis://localhost:6379
 
+# ─── Set The Url ───
+PUBLIC_APP_URL=
+
 # ─── JWT ───
 # JWT_SECRET: any long random string, minimum 32 characters
 # Generate with: node -e "console.log(require('crypto').randomBytes(32).toString('hex'))"

apps/backend/src/routes/nfc.ts

@@ -100,7 +100,7 @@ export async function nfcRoutes(app: FastifyInstance) {
       }
 
 const safeUsername = encodeURIComponent(username);
-const payloadUrl = `https://dev-card.vercel.app/${safeUsername}${
+const payloadUrl = `${process.env.PUBLIC_APP_URL}/${safeUsername}${
   cardId ? `?card=${encodeURIComponent(cardId)}` : ''
 }`;
       const response: NfcPayloadResponse = {