Using middleware crashes when accessing a route - node.js

Question

I was wondering why my router "/posts" is not running or it's just stuck loading its page when I include a middleware of app.use()
const express = require('express');
//Initialize Express
const app = express();
//Middleware
//When I comment this app.use line of code I can access the /posts router but when I left it uncommented
//My localhost sometimes error and keeps on loading
app.use('/posts',()=>{
console.log(' middleware');
});
//Ability to create routes
//ROUTES
app.get("/", (req,res)=>{
res.send('We are on Home page');
});
app.get("/posts", (req,res)=>{
res.send("Welcome back user Ice");
});
//Start Listening to our Server
app.listen(3000);

Answer 1

Based on your code, you're stuck at
app.use('/posts',()=>{
console.log(' middleware');
// You should either call next() here or respond to the HTTP here
})
To understand this, you need to get the concept of middleware in express.
You can imagine middleware like a list of function that a HTTP call should go through, depending on how you arrange it. All middleware registered with express will have access to request object req, the response object res, and the next middleware function. Among the best benefits of middleware pattern is it avoids coupling the sender of a request to the receiver by giving more than one function a chance to handle the request. Both the receiver and the sender have no explicit knowledge of each other.
Types of express middleware
Application level middleware app.use
Router level middleware router.use
Built-in middleware
express.static,express.json,express.urlencoded
Error handling middleware app.use(err,req,res,next)
Thirdparty middleware bodyparser,cookieparser
To better understand why ur code is stucked, lets look at your code again.
const express = require('express');
//Initialize Express
const app = express();
//Middleware
// You registered an application level middleware here, which its route is
// reached via http://localhost:3000/posts
// If you are going to respond here, you should first pass a `req` & `res`
// as a variable to the callback. Then you can just `res.json` `res.send`
// If you want to run some pre-processing of the or checks on the request before
// passing to other middleware, then you should call `next()` when you are done with
// the logic
app.use('/posts',()=>{
console.log(' middleware');
});
//Ability to create routes
//ROUTES
app.get("/", (req,res)=>{
res.send('We are on Home page');
});
app.get("/posts", (req,res)=>{
res.send("Welcome back user Ice");
});
//Start Listening to our Server
app.listen(3000);
If you opt for middleware case (per your question), you need to do this
app.use('/posts',(req,res,next)=>{
console.log(' middleware');
next() // This pass the control to the next middleware registered
});
// Now the request will be passed to this middleware, and runs as you expected
app.get("/posts", (req,res)=>{
res.send("Welcome back user Ice");
});