Add validateMeetingID middleware to meeting routes

middlewares/validateMeetingID.js

@@ -0,0 +1,23 @@
+const Meeting = require('../api/models/meetingModel');
+
+async function validateMeetingID(req, res, next) {
+	const { id } = req.params;
+
+	try {
+		const meeting = await Meeting.getMeetingById(id);
+		if (typeof meeting == 'undefined') {
+			return res.status(404).json({
+				message: `Meeting with id ${id} doesn't exist.`,
+			});
+		} else {
+			next();
+		}
+	} catch (error) {
+		res.status(500).json({
+			message: `Failed to fetch meeting with id ${id}.`,
+			error,
+		});
+	}
+}
+
+exports.validateMeetingID = validateMeetingID;