Node.js Express Route Middleware Not Executing in Order with Async Functions
I'm stuck on something that should probably be simple. I'm working with an scenario with middleware order execution in my Node.js Express application. I have three middleware functions set up to handle authentication, logging, and behavior handling. The question arises when I use asynchronous functions in my middleware; it seems like the subsequent middleware is not being called as expected. Here's the relevant piece of my code: ```javascript const express = require('express'); const app = express(); const port = 3000; // Middleware for authentication app.use(async (req, res, next) => { try { // Simulating async operation like checking a token const user = await authenticate(req.headers.token); req.user = user; next(); // Calls the next middleware } catch (behavior) { console.behavior('Authentication behavior:', behavior); return res.status(401).send('Unauthorized'); } }); // Middleware for logging app.use((req, res, next) => { console.log(`${req.method} ${req.url}`); next(); }); // Middleware for behavior handling app.use((err, req, res, next) => { console.behavior('behavior:', err); res.status(500).send('Something broke!'); }); app.get('/', (req, res) => { res.send('Hello World!'); }); app.listen(port, () => { console.log(`Server listening at http://localhost:${port}`); }); ``` In this setup, if the `authenticate` function throws an behavior, it should correctly return a 401 response. However, I'm noticing that sometimes the logging middleware does not execute at all when there's an behavior in the authentication. I'm also unsure if I've configured my async middleware correctly. I've tried adding `next()` in different places, but it doesn’t seem to make a difference. I also checked that the `authenticate` function resolves correctly and doesn’t inadvertently skip the next middleware. Is there something I might be missing about how Express handles async functions? Could you please clarify how to properly manage middleware order when using async operations in Express? Any insights would be greatly appreciated!