Warning test-listen is deprecated. Please use async-listen instead.

test-listen

URLs with ephemeral ports. async/await ready.

Usage

Install it:

npm install --save-dev test-listen

Pass a http.Server to test-listen and it will return an URL in the format http://localhost:{port}.

The second parameter can optionally be a hostname to return in the URL instead of localhost.

Useful for running HTTP server testsuites:

const http = require('http')
const listen = require('test-listen')

const srv = http.createServer((req, res) => res.end('1'))
const srv2 = http.createServer((req, res) => res.end('2'))

test('urls', async t => {
  let url = await listen(srv)
  t.ok(url == 'http://localhost:11401')
  let url = await listen(srv2)
  t.ok(url == 'http://localhost:42333')
})

It also works with Express:

const http = require('http')
const express = require('express')
const listen = require('test-listen')

const srv = express()

test('urls', async t => {
  let url = await listen(http.createServer(srv))
  t.ok(url == 'http://localhost:11401')
})

Or Koa:

const http = require('http')
const Koa = require('koa')
const listen = require('test-listen')

const srv = new Koa();

test('urls', async t => {
  let url = await listen(http.createServer(srv.callback()))
  t.ok(url == 'http://localhost:11401')
})

Authors

• Guillermo Rauch (@rauchg) - Vercel
• Leo Lamprecht (@notquiteleo) - Vercel