Using LocalTunnel on Macintosh

In this document we show you how to submit your running application to the autograder. The PHP autograder wants to "use" your application and test it by sending requests and checking the responses from your application.

You cannot submit a URL like http://localhost:8888/homework/guess.php because "localhost" only works for network conections originating within your computer and your computer protects your computer from incoming connectsion (i.e. they are blocked by a firewall).

Unless you install your application on a server with Internet connectivity and a domain name, you need to use a program like localtunnel to submit your program to the autograder.

Applications like localTunnel (or ngrok) can make a temporary hole through your firewall and give you a temporary domain name you can use to submit your application to the Autograder.

LocalTunnel is a free product and service and is suitable for use for this class. If you want a more full-featured product, you might be interested in "ngrok" which has a "freemium" pricing model.

Video Tutorial

You can watch a video demonstrating the use of LocalTunnel on Macintosh at:

Installing LocalTunnel

You have two choices as to how to install LocalTunel.

(a) You can visit And follow their (rather complex) instructions.


(b) If you take a look at their instructions and find them too complex, we have simplified the install into a single download:

Download LocalTunnel for Macintosh When you download the file it will probably end up in Downloads folder. You can double-click the ZIP file to unzip it to create a file named lt-mac.

To run lt-mac from the Downloads folder, in the terminal window type:

cd ~/Downloads
./lt-mac -p 8888
your url is:

You should note the temporary URL that LocalTunnel has assigned you for use later. In this example, the temporary URL is

Leave lt-mac running in this window.

You can also move the lt-mac file to another folder, perhaps into a folder that is in your path so you can execute lt-mac from any folder.

Checking Your Application Locally

First make sure that you know that your application is running on localhost:

Checking Your Application Via the Tunnel

Construct the LocalTunnel url by removing the "http://localhost:8888" and replace it with the LocalTunnel-provided URL:

Local:  http://localhost:8888/wa4e/solutions/guess/guess.php

Test that url in your browser. The LocalTunnel and local urls should return the exact same page.

Once you have verifed your application is working, submit the LocalTunnel url to the autograder.

Closing LocalTunnel

You can press CTRL-C in the LocalTunnel terminal window or simply close the LocalTunnel window.

Remember that each time you start lt-mac, it will assign you a different random address.