localtunnel

localtunnel exposes your localhost to the world for easy testing and sharing! No need to mess with DNS or deploy just to have others test out your changes.

Great for working with browser testing tools like browserling or external api callback services like twilio which require a public url for callbacks.

Quickstart

npx @desplega.ai/localtunnel --port 8000

Installation

Using npx/bunx (Recommended)

npx @desplega.ai/localtunnel --port 8000

Or with bun:

bunx @desplega.ai/localtunnel --port 8000

As a dependency in your project

npm install @desplega.ai/localtunnel

or

yarn add @desplega.ai/localtunnel

CLI usage

Use npx, bunx, or install as a project dependency to run the localtunnel CLI.

npx @desplega.ai/localtunnel --port 8000

That's it! It will connect to the tunnel server, setup the tunnel, and tell you what url to use for your testing. This url will remain active for the duration of your session; so feel free to share it with others for happy fun time!

You can restart your local server all you want, localtunnel is smart enough to detect this and reconnect once it is back.

Arguments

Below are some common arguments. See lt --help for additional arguments

• --subdomain request a named subdomain on the localtunnel server (default is random characters)
• --local-host proxy to a hostname other than localhost
• --auth protect tunnel with authentication. Use --auth alone to have the server generate a random password, or --auth <password> to specify a custom password. Username will be hi.

You may also specify arguments via env variables. E.x.

PORT=3000 lt

Examples:

npx @desplega.ai/localtunnel --port 3000 --auth                          # server generates random password
npx @desplega.ai/localtunnel --port 3000 --auth mysecretpassword         # use custom password

API

The localtunnel client is also usable through an API (for test integration, automation, etc)

localtunnel(port [,options][,callback])

Creates a new localtunnel to the specified local port. Will return a Promise that resolves once you have been assigned a public localtunnel url. options can be used to request a specific subdomain. A callback function can be passed, in which case it won't return a Promise. This exists for backwards compatibility with the old Node-style callback API. You may also pass a single options object with port as a property.

const localtunnel = require("@desplega.ai/localtunnel");

(async () => {
  const tunnel = await localtunnel({ port: 3000 });

  // the assigned public url for your tunnel
  // i.e. https://abcdefgjhij.lt.desplega.ai
  tunnel.url;

  tunnel.on("close", () => {
    // tunnels are closed
  });
})();

options

• port (number) [required] The local port number to expose through localtunnel.
• subdomain (string) Request a specific subdomain on the proxy server. Note You may not actually receive this name depending on availability.
• host (string) URL for the upstream proxy server. Defaults to https://lt.desplega.ai.
• auth (boolean | string) Enable authentication for the tunnel. Pass true to have the server generate a random password, or pass a string to use as a custom password. Username will be hi.
• local_host (string) Proxy to this hostname instead of localhost. This will also cause the Host header to be re-written to this value in proxied requests.
• local_https (boolean) Enable tunneling to local HTTPS server.
• local_cert (string) Path to certificate PEM file for local HTTPS server.
• local_key (string) Path to certificate key file for local HTTPS server.
• local_ca (string) Path to certificate authority file for self-signed certificates.
• allow_invalid_cert (boolean) Disable certificate checks for your local HTTPS server (ignore cert/key/ca options).

Refer to tls.createSecureContext for details on the certificate options.

Tunnel

The tunnel instance returned to your callback emits the following events

event	args	description
request	info	fires when a request is processed by the tunnel, contains method and path fields
error	err	fires when an error happens on the tunnel
close		fires when the tunnel has closed

The tunnel instance has the following methods

method	args	description
close		close the tunnel

server

See desplega-ai/localtunnel-server for details on the server that powers localtunnel.

License

MIT