Config Ignore Keys

Introduction

Allows the developer to ignore particular keys in the configuration and not whole configuration files.
Ignoring specific keys is the main difference between this module and Config Ignore.

Use case

If you want more granularity and more control over what you ignore, this module is for you. There are cases in which you would want to track a specific config file, but just ignore one key. For example the email address for contact forms during development could be different than that of dev environments, but the rest of the contact forms configuration should not.

Install

First you would need to install the module. In order to do this, you can either download the archive or use composer:
composer require drupal/config_ignore_keys

Usage example

After installing the project, create a plugin as in this example:

namespace Drupal\contact_form_ignore\Plugin\ConfigIgnore;

use Drupal\Core\Plugin\PluginBase;
use Drupal\config_ignore_keys\Plugin\ConfigurationIgnorePluginInterface;

/**
 * Class ContactFormIgnore.
 *
 * @ConfigurationIgnorePlugin(
 *   id = "contact_form_ignore",
 *   description = "Ignoring the receipients of the contact form configuration",
 * )
 */
class ContactFormIgnore extends PluginBase implements ConfigurationIgnorePluginInterface {

  /**
   * {@inheritdoc}
   */
  public function getConfigurations() {
    return [
      'contact.form.contact_form' => [
        'recipients',
      ],
    ];
  }

}

The plugin must be added in the src/Plugin/ConfigIgnore folder of the module implementing it.
The return value of the getConfigurations function has to be an array, with the key the config name and the value each config key you desire to ignore.