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 randomly generated forwarding URL, such as tcp://0.tcp.ngrok.io:12345 -> localhost:22.

If I run in it the background with ./ngrok tcp &, I can't find any way to see the forwarding URL. How can I run ngrok in the background and still see the URL?

score 63 · Accepted Answer · edited Jul 29 '19 at 05:57

63

There are a couple of ways.

You can either:

1) Visit localhost:4040/status in your browser to see a bunch of information, or

2) Use curl to hit the API: localhost:4040/api/tunnels

edited Jul 29 '19 at 05:57

underscorePeanutButter

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answered Dec 23 '15 at 13:40

Abe Petrillo

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score 24 · Answer 2 · edited Jun 03 '23 at 15:46

24

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.

edited Jun 03 '23 at 15:46

icodebuster

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answered Sep 09 '19 at 05:50

avalanchy

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1

In zsh for some reason, I had to prefix the '[' and ']' with '\', so here I had to run `curl -s localhost:4040/api/tunnels | jq -r .tunnels\[0\].public_url`. But works perfectly, thank! – Henrique Bruno Dec 10 '20 at 00:23
4

@HenriqueBruno for portability you can use double-quotes: `curl -s localhost:4040/api/tunnels | jq -r ".tunnels[0].public_url"` – François Leblanc Apr 30 '21 at 00:52
True! Haven't thought about it. Thanks! – Henrique Bruno Apr 30 '21 at 05:16
@François Leblanc Thanks！ – Elon May 11 '21 at 18:45
Or if you don't want to install jq: #!/bin/bash ngrok_output=$(curl --silent --show-error http://127.0.0.1:4040/api/tunnels) # Find which subdomain ngrok assigned: ngrokUrl=$(echo $ngrok_output | sed -nE 's/.*public_url":"https:..([^"]*).*/\1/p') – Ryan Aug 11 '23 at 21:43

score 19 · Answer 3 · answered Jan 03 '16 at 10:43

19

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)

answered Jan 03 '16 at 10:43

Gerard

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how can I do it with python3 with only urllib.urlopen? I don't want to 1. call the external command curl, 2. redirect to a file..Thanks – Jacquelyn.Marquardt Aug 27 '17 at 15:09
1

Why should you use curl (system dependant) and save it on a json file while you could just make an http request? – EuberDeveloper Mar 17 '21 at 11:18

score 5 · Answer 4 · edited Oct 28 '21 at 21:31

5

Run ./ngrok http & This runs the ngrok tunnel as a background process. Ngrok usually opens a window showing the assigned URL but since we are using the nohup command this is not visible.

Thus, then run curl http://127.0.0.1:4040/api/tunnels too see the URL assigned by ngrok

edited Oct 28 '21 at 21:31

M-Khawar

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answered Jan 24 '18 at 21:38

Hemanth Kondapalli

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score 4 · Answer 5 · answered Oct 05 '17 at 09:56

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)
  })

score 4 · Answer 6 · answered Nov 11 '22 at 13:34

Use the ngrok API to get all active URLs

You will need to generate a token first (https://dashboard.ngrok.com/api)

Then fetch the active endpoints from the API

curl \
-H "Authorization: Bearer {API_KEY}" \
-H "Ngrok-Version: 2" \
https://api.ngrok.com/endpoints

check documentation: https://ngrok.com/docs/api/resources/endpoints

score 3 · Answer 7 · answered Jan 08 '19 at 09:09

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)
    for i in res_json["tunnels"]:
        if i['name'] == 'command_line':
            return i['public_url']
            break

This is an edit of JUN_NETWORKS python 3 code. It outputs the HTTPS URL only. I find Ngrok will randomly change the order of which is URL is displayed first sometimes outputting HTTP. The additional loop will consistently look for the 'tunnel' named 'command_line' which is the HTTPS URL.

score 3 · Answer 8 · answered May 04 '21 at 19:51

3

The easiest way for me to check random generated URL is to go to ngrok official site > dashboard > endpoints > status and check the URLs and status of my endpoints

answered May 04 '21 at 19:51

Mykyta

71
3

1

That way the URL can't be used with programs and scripts. What if some program needs to access the ngrok URL or if you need the web page to be automatically updated with the correct link? – Chupo_cro May 21 '21 at 16:30
1

ngrok also provides API to check endpoints I described it here: https://stackoverflow.com/a/74403327/11280067 – Mykyta Nov 11 '22 at 13:37

JUN_NETWORKS · Answer 9 · 2018-11-22T16:25:33.447

2

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"]

edited Nov 22 '18 at 16:25

answered Nov 22 '18 at 16:13

JUN_NETWORKS

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score 2 · Answer 10 · answered Jun 11 '20 at 06:44

2

If you love PowerShell, here it is in variables.

$ngrokOutput = ConvertFrom-Json (Invoke-WebRequest -Uri http://localhost:4040/api/tunnels).Content
$httpsUrl = $ngrokOutput.tunnels.public_url[0]
$httpUrl = $ngrokOutput.tunnels.public_url[1]

answered Jun 11 '20 at 06:44

Johnny

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score 1 · Answer 11 · answered Nov 28 '18 at 21:17

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

score 0 · Answer 12 · answered Jan 02 '21 at 04:08

A Node.js solution.

Bonus: It copies the url to the clipboard in Windows, Mac and Linux¹

const http = require("http");
const { execSync } = require("child_process");

const callback = (res) => {
    let data = "";
    res.on("data", (chunk) => (data += chunk));
    res.on("end", () => {
        const resJSON = JSON.parse(data);
        const tunnels = resJSON.tunnels;

        const { public_url: url } = tunnels.find(({ proto }) => proto === "https");

        console.log(url);

        // Copy to clipboard
        switch (process.platform) {
            case "win32":
                execSync(`echo ${url} | clip`);
                break;
            
            case "darwin":
                execSync(`echo ${url} | pbcopy`);
                break;
                
            case "linux":
                // NOTE: this requires xclip to be installed
                execSync(`echo ${url} | xclip -selection clipboard`);
                break;
                
            default:
                break;
        }
    });
};

http.get("http://localhost:4040/api/tunnels", callback);

[1] You need to install xclip first:

sudo apt-get install xclip

Alex Cory · Answer 13 · 2021-02-17T21:32:33.383

0

If you're using nodejs I did this

const getURL = async () => {
  // inspect if the callback is working at: http://127.0.0.1:4040/inspect/http 
  const ngrok = await import('ngrok')
  const api = ngrok.getApi();
  const { tunnels } = JSON.parse(await api?.get('api/tunnels') ?? '{}')
  // if we already have a tunnel open, disconnect. We're only allowed to have 4
  if (tunnels?.length > 0) await ngrok.disconnect()
  return await ngrok.connect(3000)
}

edited Feb 17 '21 at 21:32

answered Feb 17 '21 at 02:23

Alex Cory

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use const tunnels = await api.listTunnels(); instead of api.get as its deprecated – Shalabyer Jun 24 '21 at 21:05

score 0 · Answer 14 · answered Mar 20 '23 at 11:38

Here is a C# solution that fetches first URL from ngrok Agent API provided by localhost:4040/api.

//fetch xml from API `api/tunnels/command_line`
using var httpClient = new HttpClient();
var request = new HttpRequestMessage(HttpMethod.Get, 
    "http://localhost:4040/api/tunnels/command_line");
request.Headers.Add(HttpRequestHeader.Accept.ToString(), "application/xml");
var response = await httpClient.SendAsync(request);
var content = await response.Content.ReadAsStringAsync();

//parse and get the first PublicURL element's text
const string Xpath = "/tunnelResource/PublicURL";
var xmlDocument = new XmlDocument();
xmlDocument.LoadXml(content);
var xmlNode = xmlDocument.SelectSingleNode(Xpath);
var xmlElement = xmlNode as XmlElement;
var url = xmlElement.InnerText;

score -1 · Answer 15 · answered Aug 08 '17 at 22:08

May be I'm a little too late in answering but would be glad if it is helpful for anyone visiting the question.

***Above answers are solutions to see/check the redirection URL. However to run ngrok in background, you could try using screen in linux . Incase you need help here a quick reference

Steps: 1. Just run the ngrok in screen and then detach. 2. Use the python script given by Gerard above to see the URL.

I have followed the same process and it works!

score -1 · Answer 16 · answered Jan 18 '19 at 10:22

-1

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

answered Jan 18 '19 at 10:22

Jirawat Kusolpredee

47
1
6

View random ngrok URL when run in background

16 Answers16

A Node.js solution.

Linked