Improve support for settings.local.php in generated configuration

[xurizaemon]

Drupal supports a settings.local.php override intended to support local overrides to configuration in settings.php.

/**
 * Load local development override configuration, if available.
 *
 * Create a settings.local.php file to override variables on secondary (staging,
 * development, etc.) installations of this site.
 *
 * Typical uses of settings.local.php include:
 * - Disabling caching.
 * - Disabling JavaScript/CSS compression.
 * - Rerouting outgoing emails.
 *
 * Keep this code block at the end of this file to take full effect.
 */
#
# if (file_exists($app_root . '/' . $site_path . '/settings.local.php')) {
#   include $app_root . '/' . $site_path . '/settings.local.php';
# }

ISLE buildkit update_settings_php configuration is placed last in generated settings.php via echo ... >> settings.php.

Calling make up in ISLE DC will call update_settings_php each time:

https://github.com/Islandora-Devops/isle-dc/blob/4f5bebcd12ed3aa3145b57f4cd7774c60d9f806f/Makefile#L258-L266

I wondered if drush islandora:settings:* calls support "upserting" configuration in settings.php, in which case I'd expect moving the block to permit the file order to persist. It does look like the code might support persisting locations in that file if the settings block was moved after generation?

isle-buildkit/drupal/rootfs/usr/share/drush/Commands/UpdateSettingsCommands.php

Lines 218 to 231 in 2a2c931

	/**
	* Determine which settings file to update.
	*/
	private function writeSettings($settings)
	{
	require_once DRUPAL_ROOT . '/core/includes/install.inc';
	$settings_file = $this->getSettingFilePath();
	$fs = new Filesystem();
	$fs->chmod($settings_file, 0755);
	new Settings([]);
	drupal_rewrite_settings($settings, $settings_file);
	$fs->chmod($settings_file, 0400);
	}
	}

Templating the configuration in so that it appears before the inclusion of settings.local.php would support environment-specific overrides to settings.php when update_settings_php is called after initial build.

[nigelgbanks]

I would like to push folks to not modify settings.php at container startup, but rather take the approach used in the isle-site-template. That reads the settings passed in via the environment or secrets. Ideally, these custom drush commands will get removed from isle-buildkit. The plan is to deprecate them for this next release and remove them in the next after that.

For example this line takes its value from the DRUPAL_DEFAULT_BROKER_URL environment variable.

This technique should be used with the drupal-scaffold feature of composer to append some text on to default.settings.php and write out to settings.php on composer install, such that it's baked into the Docker image. As is done in the starter site here

[xurizaemon]

That looks much better.

I'll leave this issue open on the assumption that Isle Buildkit is still under development, in case the proposal has merit here. If isle-site-template is the path ahead, happy for this issue to be closed.

Thanks @nigelgbanks!