Dcycle Blog

A Drupal 8 site deployment module

September 10, 2014

Here is what you might have in a site deployment module for Drupal 8.

In mysite_deploy.info.yml:

type: module
name: 'mysite_deploy'
core: '8.x'

In mysite_deploy.module:

 * @file
 * site deployment functions
use Drupal\Core\Extension\InfoParser;

 * Updates dependencies based on the site deployment's info file.
 * If during the course of development, you add a dependency to your
 * site deployment module's .info file, increment the update hook
 * (see the .install module) and this function will be called, making
 * sure dependencies are enabled.
function mysite_deploy_update_dependencies() {
  $parser = new InfoParser;
  $info_file = $parser->parse(drupal_get_path('module', 'mysite_deploy') . '/mysite_deploy.info.yml');
  if (isset($info_file['dependencies'])) {
    \Drupal::moduleHandler()->install($info_file['dependencies'], TRUE);

 * Set the UUID of this website.
 * By default, reinstalling a site will assign it a new random UUID, making
 * it impossible to sync configuration with other instances. This function
 * is called by site deployment module's .install hook.
 * @param $uuid
 *   A uuid string, for example 'e732b460-add4-47a7-8c00-e4dedbb42900'.
function mysite_deploy_set_uuid($uuid) {
    ->set('uuid', $uuid)

An in mysite_deploy.install:

 * @file
 * site deployment install functions

 * Implements hook_install().
function mysite_deploy_install() {
  // This module is designed to be enabled on a brand new instance of
  // Drupal. Settings its uuid here will tell this instance that it is
  // in fact the same site as any other instance. Therefore, all local
  // instances, continuous integration, testing, dev, and production
  // instances of a codebase will have the same uuid, enabling us to
  // sync these instances via the config management system.
  // See also https://www.drupal.org/node/2133325
  for ($i = 7001; $i < 8000; $i++) {
    $candidate = 'mysite_deploy_update_' . $i;
    if (function_exists($candidate)) {

 * Update dependencies and revert features
function mysite_deploy_update_7003() {
  // If you add a new dependency during your development:
  // (1) add your dependency to your .info file
  // (2) increment the number in this function name (example: change
  //     change 7003 to 7004)
  // (3) now, on each target environment, running drush updb -y
  //     will call the mysite_deploy_update_dependencies() function
  //     which in turn will enable all new dependencies.

The only real difference between a site deployment module for D7 and D8, thus, is that the D8 version must define a UUID common to all instances of a website (local, dev, prod, testing…).