Background

I am a developer that building service that need call back and test in my local. One of the very useful service provider is localtunnel.me. But my service contain sensitive data, so use their service may not be good enough.

Thanks that localtunnel server is open source that we can build and hold my own.

I see the official doc do not describe detail. Below is detail steps that i create with my own localtunnel

Get Ready

Before start, we need to prepare below:

1. VPS, in my case i use aws lightsail. Of course, vultr, linode are also good choice.
2. Domain name for your VPS, just go any domain name seller to buy one like Godaddy. We will setup wildcard subdomain.

Let's Start

1. Set up in VPS

Set up aws lightsail

In my case, i just start Ubuntu OS in aws lightsail, detail is skipped here, follow AWS guide is good enough.

One thing must to do is we need allow all TCP going to aws. Just go lightsail console, Networking tab, Firewall section, add All TCP to the rule.

Install softwares to VPS

1. SSH to server and become root user

ssh ubuntu@{your VPS IP}
sudo su

2. Install softwares

# update apt
apt-get update 

# install git, docker
apt-get install -y git docker

# install docker-compose, ref: https://docs.docker.com/compose/install/
curl -L "https://github.com/docker/compose/releases/download/1.24.0/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
chmod +x /usr/local/bin/docker-compose
ln -s /usr/local/bin/docker-compose /usr/bin/docker-compose

2. Domain Setting

Base on your domain provider will have different setup. But in general, 2 things need to be set:

1. set Type A with Name lt point your VPS IP
2. set Type A with Name *.lt point your VPS IP

Remember you need wait at least 30 minutes that domain change take effect

3. Get SSL Cert

Because my callback service need https, so i need SSL cert. I use certbot for free cert. Certbot will be expired every 3 months, so becareful remember to renew.

Set up cerbot

Still use root in your VPS

# get certbot
git clone https://github.com/certbot/certbot

# cd to folder
cd /certbot

# start certbot domain check, you need replace with your domain
./certbot-auto certonly --manual -d *.lt.{YOUR_DOMAIN} -d lt.{YOUR_DOMAIN} --agree-tos --manual-public-ip-logging-ok --preferred-challenges dns-01 --server https://acme-v02.api.letsencrypt.org/directory

# you will see below, you need go back to your domain provider to setup 
--------------------------------------------------------------------
Please deploy a DNS TXT record under the name
_acme-challenge.lt.{YOUR_DOMAIN} with the following value:

MfXTzyYTiASihTo1t6gO-zr-v6A8wQBPOb2OehhY7AM

Before continuing, verify the record is deployed.
--------------------------------------------------------------------
Press Enter to Continue
--------------------------------------------------------------------
Please deploy a DNS TXT record under the name
_acme-challenge.lt.{YOUR_DOMAIN} with the following value:

MfXTzyYTiASihTo1t6gO-zr-v6A8wQBPOb2OehhY7AM

Before continuing, verify the record is deployed.
--------------------------------------------------------------------
Press Enter to Continue

# when done you will see successful message and find cert in path: /etc/letsencrypt/archive/lt.{YOUR_DOMAIN}

4. Set up Localtunnel Server

We need clone this project as template, and update some config to your own.

Config

# clone this project 
git clone https://github.com/TONYHOKAN/docker_nginx_localtunnel.git

# go to project folder
cd docker_nginx_localtunnel/

# copy .env_sample to .env and update DOMAIN key in .env to your own
cp .env_sample .env

# set up cert from certbot for nginx 
cp /etc/letsencrypt/archive/lt.{YOUR_DOMAIN}/fullchain.pem /ssl/server.crt
cp /etc/letsencrypt/archive/lt.{YOUR_DOMAIN}/privkey.pem /ssl/server.key 

Start Localtunnel with Docker

We use docker to run our server

# build image
docker-compose build

# run the server in docker_nginx_localtunnel/ directory
docker-compose up

# after start, you will see message
Starting localtunnel_server ... done
Starting localtunnel_nginx  ... done
Attaching to localtunnel_server, localtunnel_nginx
localtunnel_server    | 2019-05-25T16:29:50.530Z koa-router defined route HEAD,GET /api/status
localtunnel_server    | 2019-05-25T16:29:50.533Z koa-router defined route HEAD,GET /api/tunnels/:id/status
localtunnel_server    | 2019-05-25T16:29:50.534Z koa:application use dispatch
localtunnel_server    | 2019-05-25T16:29:50.535Z koa:application use allowedMethods
localtunnel_server    | 2019-05-25T16:29:50.535Z koa:application use -
localtunnel_server    | 2019-05-25T16:29:50.536Z koa:application use -
localtunnel_server    | 2019-05-25T16:29:50.545Z localtunnel server listening on port: 3000

# try curl with your server
curl https://lt.{YOUR_DOMAIN}

# you will see message
localtunnel_nginx     | 210.6.196.42 - - [25/May/2019:16:33:52 +0000] "GET / HTTP/1.1" 404 169 "-" "curl/7.54.0"

# you are done!!

5. Test in Local

Everthing work fine until this step, you can start localtunnel in your local now.

# in your local, install localtunnel client 
npm install -g localtunnel

# start localtunnel client connection
lt -h https://lt.{YOUR_DOMAIN} -p 8080 --subdomain test

# you will see return new url
your url is: https://test.lt.{YOUR_DOMAIN}

# now everyone can go https://test.lt.{YOUR_DOMAIN} to access your local site