Implementing and using a third-party PHP library

Drupal 8 uses Composer for package dependencies and autoloading classes based on PSR standards. This allows us to use any available PHP library much more easily than in previous versions of Drupal.

In this recipe, we will add the IpRestrict Stack Middleware library to add the functionality to whitelist access to the Drupal site based on allowed IP addresses.

Getting ready

You need to have Composer installed in order to use the Composer manager workflow. You can follow the Getting Started documentation at https://getcomposer.org/doc/00-intro.md. We will add the alsar/stack-ip-restrict library as a dependency to our Drupal installation.

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