project done

middleware/checkObjectId.js

@@ -0,0 +1,9 @@
+const mongoose = require('mongoose');
+// middleware to check for a valid object id
+const checkObjectId = (idToCheck) => (req, res, next) => {
+  if (!mongoose.Types.ObjectId.isValid(req.params[idToCheck]))
+    return res.status(400).json({ msg: 'Invalid ID' });
+  next();
+};
+
+module.exports = checkObjectId;