Preprocess

This module provides a plugin type for preprocessing. The manager scans for implementations and executes the preprocessors when they meet the given `hook`
criteria. It is designed to make preprocessing more structural and more clearly for themers.

• Provides a plugin type that you can use in your theme or module
• Theme plugins are discovered through YML, by creating a MY_THEME.preprocessors.yml you can register them.

With this module you no longer have to write all your preprocessing in your THEME.theme or module file. You gain the possibility to focus preprocessing on specific elements without having to write so many conditional checks for one specific hook implementation to cover all cases.

Yes, this module will help you write more generic, structural and cleaner preprocessing.

Yes, you will gain the possibility to write Object-oriented preprocessing, providing more flexibility and better integration.

No, it does nothing out of the box, you will have to write your own implementations, just as you would with hook_preprocess_HOOK, for any preprocessing you like.

Installation

This module can be installed as any other Drupal module and needs no extra configuration.

Note that if you want to rely on this module in your theme the dependency can't be set explicitly until #474684: Allow themes to declare dependencies on modules is resolved. You will need to make sure the preprocess module is enabled manually.