Backport Composer

A very lightweight module that registers Composer's Autoloader in Drupal 7.

This module is primarily to support the Backport module as the preferred or "native" Composer solution in Drupal 7, similar to what is now done in Drupal 8.

This is a standalone implementation and not a comprehensive solution like Composer Manager.

Installation

1. Copy the module into your sites/all/modules folder.
2. Go to /admin/modules and enable the Backport Composer in the Utilities section (or if you use Drush: drush en backport_composer).

Setup

By default, this module should immediately work "out-of-the-box" as it attempts to automatically locate the first viable autoload.php file it can find.

The locations in which it searches depends greatly on how the site is configured and which modules are used.

There are five "root" paths this module checks:

1. Drupal Root (indicates project level management):
   • DRUPAL_ROOT
2. One level above Drupal Root (indicates project level management):
   • DRUPAL_ROOT/..
3. Site specific files (whatever the variable file_default_scheme is set to):
   • public://
4. Site specific directory:
   • sites/example.com or sites/default as a fallback
5. All sites directory:
   • sites/all

Finally, for each of the above ROOT paths, this module will check if autoload.php exists at one of the following locations:

• ROOT/autoload.php
• ROOT/vendor/autoload.php
• ROOT/composer/autoload.php
• ROOT/composer/vendor/autoload.php
• ROOT/composer_manager/autoload.php
• ROOT/composer_manager/vendor/autoload.php

This module only supports Composer Manager locations solely for the express purpose of easier transitioning or migration to a more "native" Composer workflow. This module should not be used if Composer Manager is installed.

Configuration

If you have Composer installed at a different location there are a couple ways you can customize which autoloader is used:

1. Create a custom file in the root of your site (e.g. ./DOCROOT/autoload.php) and then return the require of the Composer's autoload.php file from whichever location you need (similar to what Drupal 8 does):
   

   return require '../../../sites/example.com/files/vendor/autoload.php';
   

2. Set the following variable in your site's settings.php file to a path where Composer's autoload.php file resides:
   

   $conf['backport_composer_autoload_path'] = DRUPAL_ROOT . '/../../../sites/example.com/files/vendor/autoload.php';
   

Notes

1. The location of the Composer autoload.php file is cached, even if set as a variable in your settings.php or settings.local.php file. This is to ensure that an absolute path is always ascertained in the event the variable uses relative positioning or contains any symbolic links. If its location changes, you will need to clear the database cache for it to be rediscovered. This is primarily to reduce unnecessary file system checks on each bootstrap.
2. If you create a custom autoload.php which requires another autoload.php, you should always explicitly use require instead of require_once as the latter will return TRUE instead of the autoloader if it has already been required in PHP (which is a possibility).
3. If the variable backport_composer_autoload_path is set, it will always take precedence over any automated discovery if it is a valid path. If it isn't, it will fallback to automated discovery.
4. If the variable page_cache_without_database is set, it is also highly recommended that you explicitly set the backport_composer_autoload_path variable as not doing so may cause more than one intended file system check to determine the absolute path of the autoload.php file as any cached value stored in the database will not be retrievable.
5. If the variable page_cache_invoke_hooks has been disabled, Composer's autoload.php will not be invoked or registered. This is a limitation of how page caching works and you will need to figure out a way to circumvent this and manually invoke backport_composer_autoloader() if its functionality is desired at this step of the bootstrap phase.