feat: upload service account credentials

server/src/routes/integration.ts

@@ -0,0 +1,12 @@
+import { Router } from 'express';;
+import { google, sheets_v4 } from "googleapis";
+
+export const router = Router()
+
+
+router.post('/upload-credentials', (req, res) => {
+    const credentials = req.body.credentials;
+  
+    if (!credentials) {
+      return res.status(400).json({ message: 'Credentials are required.' });
+    }