Config Split Merge

A tool to merge together separate configurations for Drupal 8 sites.

Taking a primary configuration this tool will analyse the configuration available and perform the following actions.

• If the configuration exists in the primary and not in the secondary then leave it alone and add it to the primary config split blacklist.
• If the configuration exists in both sites and there is no difference between the two sites then the configuration is placed into a default configuration area.
• If the configuration exists in both sites and that configuration is different then add this configuration to the configuration split grey list for both sites and make a copy in the default configuration.
• If the configuration exists in both sites, contains a single difference, and that difference is just the uuid, then copy the primary configuration to the default configuration area and delete the sibling configuration file. This step also generates output in the form of a update hook that can be used to update the uuid for all sites.

The tool doesn't understand Drupal configuration, just the YAML structure that it contains.

Install

Just install the tool using composer into your Drupal codebase.

composer require --dev hashbangcode/config_split_merge

Once you have used it you can then remove the tool from your site.

composer remove --dev hashbangcode/config_split_merge

The tool is a one-shot deal and should only be used when you have problems with your config in a multi-site setup.

Setup

You first need to ensure that the configuration split config files have been created for the configurations you want to merge. You don't need to install the configuration splits on all sites, but the config files need to exist.

The tool needs minimal setup, you just need to ensure that the configuration directory structure looks something like this.

/config/default
/config/default/config_split.config_split.parent.yml
/config/default/config_split.config_split.child1.yml
/config/default/config_split.config_split.child2.yml
/config/parent
/config/child1
/config/child2

You can alter the location of the 'default' directory by passing the --config flag with a value of the directory.

Usage

NOTE: This tool will alter the config directories in-situ, i.e. it will permanently alter your config directories. Make sure you have adequate backups before hand!

Run the tool by passing the parent and child directories that need analysis.

./vendor/bin/config_split_merge drupal:config_split_merge parent child

You can provide multiple child directories by separating them with a comma.

./vendor/bin/config_split_merge drupal:config_split_merge parent child1,child2

By default the configuration area is assumed to be located at 'config', relative to the other two directories. You can set this location by passing in the --config flag.

./vendor/bin/config_split_merge drupal:config_split_merge parent child --config=sync/config

If applicable, the tool will also output the result of any config that is shared between sites, but that needs to be altered in the database before it can be used on one of the sites. This is in the form of an update hook that can be added to the install profile or module of your choice. This update should be run on all sites.

<?php

/**
 * Fix the uuid information on certain configs.
 */
function my_module_update_8001() {
  $fieldChanges = [
    'node.type.landing_page' => '2034e796-4d2c-43f0-9135-1afc93052380',
  ];

  foreach ($fieldChanges as $field => $uuid) {
    $config = \Drupal::service('config.factory')->getEditable($field);
    $config->set('uuid', $uuid)->save();
  }
}

You can get the tool to put this output in a file with the --update-hook-file flag.

Once the tool has run you will need to import and export the configuration to ensure all sites are set up correctly.

Arguments

The tool takes two arguments.

parent - The parent directory that will be treated as the primary site.

children - The children directories that will be treated as the sub-sites. Either a single value or a comma separated list.

Flags

The following flags can be passed to the tool

Flag	Shortcut	Default	Description
--config	-c	config	Set the config directory root.
--update-hook-file	-u	FALSE	If set then this file of this name will be created and filled with the update hook. Otherwise it will be output to screen.
--dry-run	-d	FALSE	Perform a dry run, alters no files.
--verbose	-v	FALSE	Print out a lot of debug information.

@TODO

This tool comes from a proof of concept that seemed to work for a given situation. As a result there are absolutely things that could be improved or altered.

• Better output/reporting.
• Incorporate a config ignore option to separate configs for certain sites.
• More tests!