View random ngrok URL when run in background

Question

When I start an ngrok client with ./ngrok tcp 22 it runs in the foreground and I can see the randoming generated forwarding URL, such as tcp://0.tcp.ngrok.io:

Answer 1

If it helps anyone I wrote a quick script to extract the generated random url in Node:

It makes assumption you're only interested in the secure url.

const fetch = require('node-fetch')
fetch('http://localhost:4040/api/tunnels')
  .then(res => res.json())
  .then(json => json.tunnels.find(tunnel => tunnel.proto === 'https'))
  .then(secureTunnel => console.log(secureTunnel.public_url))
  .catch(err => {
    if (err.code === 'ECONNREFUSED') {
      return console.error("Looks like you're not running ngrok.")
    }
    console.error(err)
  })

If you wanted all tunnels:

const fetch = require('node-fetch')
fetch('http://localhost:4040/api/tunnels')
  .then(res => res.json())
  .then(json => json.tunnels.map(tunnel => tunnel.public_url))
  .then(publicUrls => publicUrls.forEach(url => console.log(url)))
  .catch(err => {
    if (err.code === 'ECONNREFUSED') {
      return console.error(
        "Looks like you're not running ngrok."
      )
    }
    console.error(err)
  })

Answer 2

This little Python (2.7) script will call the ngrok API and print the current URL's:

import json
import os 

os.system("curl  http://localhost:4040/api/tunnels > tunnels.json")

with open('tunnels.json') as data_file:    
    datajson = json.load(data_file)


msg = "ngrok URL's: \n'
for i in datajson['tunnels']:
  msg = msg + i['public_url'] +'\n'

print (msg)

Answer 3

In Python3

import json
import requests


def get_ngrok_url():
    url = "http://localhost:4040/api/tunnels"
    res = requests.get(url)
    res_unicode = res.content.decode("utf-8")
    res_json = json.loads(res_unicode)
    return res_json["tunnels"][0]["public_url"]

This returned json have 2 url for http and https. If you want only https url, you res_json["tunnels"][index num]["proto"]

Answer 4

There is a better way to do that just login to your account on ngrok.com. Your URL will be in your dashboard.

Answer 5

If you want to get the first tunnel then jq will be your friend:

curl -s localhost:4040/api/tunnels | jq -r .tunnels[0].public_url

When running more than one instance of ngrok then use the tunnel name /api/tunnels/:name.

Answer 6

In Ruby

require 'httparty'

# get ngrok public url
begin
  response = HTTParty.get 'http://localhost:4040/api/tunnels'
  json = JSON.parse response.body
  new_sms_url = json['tunnels'].first['public_url']
rescue Errno::ECONNREFUSED
  print 'no ngrok instance found. shutting down'
  exit
end