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self-hosted regex101

Running Regex101 Offline #

This is taken from the Intrepid individual’s github blog1

3 am on May 30, 2015 #

I was working on something when I suddenly needed some regex-fu. I opened a new browser tab, typed regex101 and pressed enter, and then I realized, I am at a place where sites usually take five fucking minutes to load up. I thought:

We need to improvise

I needed something that could work offline. I googled around (which took ages) to find an offline tool, but none of the results impressed me, and then I found this - a way of getting regex101 itself working offline. Turns out, some wget magic is all that we needed.

Cloning the site locally took around 10 minutes:

wget to the rescue
mkdir ~/regex101
cd ~/regex101
wget -r --no-host-directories --no-parent
wget --output-document ./js/javascript.regex101.js;
wget --output-document ./js/pcre.regex101.js;
wget --output-document ./js/pcrelib16.js;

I used python’s http.server module to host the site:

python, serve me a regex
  python3 -m http.server 8090
The site loaded, but a few things were still out of place, like it still tried fetching jquery, font awesome, a font from google fonts etc.

I then manually fetched each and every dependency, and edited the index.html to use the local ones.

Thirty minutes later I had a fully offline version up and running.

But we’re not done yet. I am not gonna cd into some directory and run python3 -m http.server 8090 everytime I need regexes.

We need to improvise.

Thanks to Linux Utility Lab, I learnt how to host sites using Apache this semester. I already had apache2 installed. The rest was easy:

  • Create a directory that will host all the files:

    > sudo mkdir -p /var/www/

  • Put all the site required files there:

    make a deposit
    sudo cp -r ~/regex101 /var/www/

  • Create a site configuration:

  • Copy default: sudo cp /etc/apache2/sites-available/000-default.conf /etc/apache2/sites-available/

  • Vim-it: sudo vim /etc/apache2/sites-available/

Here’s how my config looked:

<VirtualHost *:80>

  DocumentRoot /var/www/
Now edit the hosts file to have a working url:

  • Open: sudo vim /etc/hosts

  • Add line:

  • Enable the site sudo a2ensite

  • restart the server. sudo service apache2 restart I now have a fully functional Regex101 running locally at:

I don’t even remeber what I wanted to do with regexes in the first place. So, I decided to write down a blog post.

By the way, It’s Four In The Morning.