App Mountpath - Expressjs

<h3 id='app.mountpath'>app.mountpath</h3>

The app.mountpath property contains one or more path patterns on which a sub-app was mounted.

<div class="doc-box doc-info" markdown="1"> A sub-app is an instance of `express` that may be used for handling the request to a route. </div>

const express = require('express')

const app = express() // the main app
const admin = express() // the sub app

admin.get('/', (req, res) => {
  console.log(admin.mountpath) // /admin
  res.send('Admin Homepage')
})

app.use('/admin', admin) // mount the sub app

It is similar to the baseUrl property of the req object, except req.baseUrl returns the matched URL path, instead of the matched patterns.

If a sub-app is mounted on multiple path patterns, app.mountpath returns the list of patterns it is mounted on, as shown in the following example.

const admin = express()

admin.get('/', (req, res) => {
  console.log(admin.mountpath) // [ '/adm{*splat}n', '/manager' ]
  res.send('Admin Homepage')
})

const secret = express()
secret.get('/', (req, res) => {
  console.log(secret.mountpath) // /secr{*splat}t
  res.send('Admin Secret')
})

admin.use('/secr{*splat}t', secret) // load the 'secret' router on '/secr{*splat}t', on the 'admin' sub app
app.use(['/adm{*splat}n', '/manager'], admin) // load the 'admin' router on '/adm{*splat}n' and '/manager', on the parent app