Testing and Developing WordPress Plugins using Vagrant to provide the test environment

I keep trundling back to a collection of WordPress plugins that I really love. And sometimes I want to contribute patches to the plugin.

I don’t want to develop against this server (that would be crazy… huh… right… no one does that… *cough*) but instead, I want a nice, fresh and new WordPress instance to just check that it works the way I was expecting.

So, I created a little Vagrant environment, just for testing WordPress plugins. I clone the repository for the plugin, and create a “TestingEnvironment” directory in there.

I then create the following Vagrantfile.

Vagrant.configure("2") do |config|
  config.vm.box = "ubuntu/jammy64"
  # This will create an IP address in the range 192.168.64.0/24 (usually)
  config.vm.network "private_network", type: "dhcp"
  # This loads the git repo for the plugin into /tmp/git_repo
  config.vm.synced_folder "../", "/tmp/git_repo"

  # If you've got vagrant-cachier, this will speed up apt update/install operations
  if Vagrant.has_plugin?("vagrant-cachier")
    config.cache.scope = :box
  end

  config.vm.provision "shell", inline: <<-SHELL

    # Install Dependencies
    apt-get update
    apt-get install -y apache2 libapache2-mod-fcgid php-fpm mysql-server php-mysql git

    # Set up Apache
    a2enmod proxy_fcgi setenvif
    a2enconf "$(basename "$(ls /etc/apache2/conf-available/php*)" .conf)"
    systemctl restart apache2
    rm -f /var/www/html/index.html

    # Set up WordPress
    bash /vagrant/root_install_wordpress.sh
  SHELL
end

Next, let’s create that root_install_wordpress.sh file.

#! /bin/bash

# Allow us to run commands as www-data
chsh -s /bin/bash www-data
# Let www-data access files in the web-root.
chown -R www-data:www-data /var/www

# Install wp-cli system-wide
curl -s -S -O https://raw.githubusercontent.com/wp-cli/builds/gh-pages/phar/wp-cli.phar
mv wp-cli.phar /usr/local/bin/wp
chmod +x /usr/local/bin/wp

# Slightly based on 
# https://www.a2hosting.co.uk/kb/developer-corner/mysql/managing-mysql-databases-and-users-from-the-command-line
echo "CREATE DATABASE wp;" | mysql -u root
echo "CREATE USER 'wp'@'localhost' IDENTIFIED BY 'wp';" | mysql -u root
echo "GRANT ALL PRIVILEGES ON wp.* TO 'wp'@'localhost';" | mysql -u root
echo "FLUSH PRIVILEGES;" | mysql -u root

# Execute the generic install script
su - www-data -c bash -c /vagrant/user_install_wordpress.sh
# Install any plugins with this script
su - www-data -c bash -c /vagrant/customise_wordpress.sh
# Log the path to access
echo "URL: http://$(sh /vagrant/get_ip.sh) User: admin Password: password"

Now we have our dependencies installed and our database created, let’s get WordPress installed with user_install_wordpress.sh.

#! /bin/bash

# Largely based on https://d9.hosting/blog/wp-cli-install-wordpress-from-the-command-line/
cd /var/www/html
# Install the latest WP into this directory
wp core download --locale=en_GB
# Configure the database with the credentials set up in root_install_wordpress.sh
wp config create --dbname=wp --dbuser=wp --dbpass=wp --locale=en_GB
# Skip the first-run-wizard
wp core install --url="http://$(sh /vagrant/get_ip.sh)" --title=Test --admin_user=admin --admin_password=password --admin_email=example@example.com --skip-email
# Setup basic permalinks
wp option update permalink_structure ""
# Flush the rewrite schema based on the permalink structure
wp rewrite structure ""

Excellent. This gives us a working WordPress environment. Now we need to add our customisation – the plugin we’re deploying. In this case, I’ve been tweaking the “presenter” plugin so here’s the customise_wordpress.sh code:

#! /bin/bash

cd /var/www/html/wp-content/plugins
git clone /tmp/git_repo presenter --recurse-submodules
wp plugin activate presenter

Actually, that /tmp/git_repo path is a call-back to this line in the Vagrantfile: config.vm.synced_folder "../", "/tmp/git_repo".

And there you have it; a vanilla WordPress install, with the plugin installed and ready to test. It only took 4 years to write up a blog post for it!

As an alternative, you could instead put the plugin you’re working with in a subdirectory of the Vagrantfile and supporting files, then you’d just need to change that git clone /tmp/git_repo line to git clone /vagrant/MyPlugin – but then you can’t offer this to the plugin repo as a PR, can you? 😀

Featured image is “Killer travel plug and socket board” by “Ashley Basil” on Flickr and is released under a CC-BY license.