You can create chainable route handlers for a route path by using app.route(). Because the path is specified at a single location, creating modular routes is helpful, as is reducing redundancy and typos

Here is an example of chained route handlers that are defined by using app.route().

app.route('/book')
  .get((req, res) => {
    res.send('Get a random book')
  })
  .post((req, res) => {
    res.send('Add a book')
  })
  .put((req, res) => {
    res.send('Update the book')
  })

express.Router

Use the express.Router class to create modular, mountable route handlers. A Router instance is a complete middleware and routing system; for this reason, it is often referred to as a “mini-app”.

The following example creates a router as a module, loads a middleware function in it, defines some routes, and mounts the router module on a path in the main app.

Create a router file named birds.js in the app directory, with the following content:

const express = require('express')
const router = express.Router()

// middleware that is specific to this router
router.use((req, res, next) => {
  console.log('Time: ', Date.now())
  next()
})
// define the home page route
router.get('/', (req, res) => {
  res.send('Birds home page')
})
// define the about route
router.get('/about', (req, res) => {
  res.send('About birds')
})

module.exports = router

Then, load the router module in the app:

const birds = require('./birds')

// ...

app.use('/birds', birds)