Using Redis with Drupal 7.x

There are two options for using Redis with Drupal on Platform.sh, you can either use the PhpRedis extension or the Predis library.

Requirements

You will need to add the Redis module to your project.

If you are using a make file, you can add those lines to your project.make.

projects[redis][version] = 3.11

To use the Predis library also add it to your make file:

libraries[predis][download][type] = get
libraries[predis][download][url] = https://github.com/nrk/predis/archive/v1.0.tar.gz
libraries[predis][directory_name] = predis
libraries[predis][destination] = libraries

• drush_make_files

To use the PhpRedis extension you will need to add it to your .platform.app.yaml file.

# Additional extensions
runtime:
    extensions:
        - redis

• application_configuration

Configuration

To make use of the Redis cache you will need to set some Drupal variables. You can either do this in your settings.php file or by setting Platform Variables directly via the UI.

Via the Web Interface

The advantage of using environment variables is that these won't be used in your local build where you might not have Redis installed.

Add the following environment variables using the Platform.sh Web Interface. Note, if you set a directory in the make file you will need to alter the variables to match.

drupal:cache_backends

[
   "sites/all/modules/redis/redis.autoload.inc"
]

note Remember to tick the JSON Value box.

note Use the actual path to your Redis module in case it is in a different location. For example: sites/all/modules/contrib/redis.

drupal:redis_client_host

redis.internal

drupal:redis_client_interface

Predis

Or

PhpRedis

drupal:cache_default_class

Redis_Cache

drupal:cache_class_cache_form

DrupalDatabaseCache

Via settings.php

If you prefer to commit these variables directly to your settings.php, here are the lines to add:

$conf['redis_client_interface'] = 'Predis';

Or

$conf['redis_client_interface'] = 'PhpRedis';

Then (after the settings.local.php include):

if (!empty($_ENV['PLATFORM_RELATIONSHIPS'])) {
  $relationships = json_decode(base64_decode($_ENV['PLATFORM_RELATIONSHIPS']), TRUE);
  $conf['redis_client_host'] = $relationships['redis'][0]['host'];
  $conf['redis_client_port'] = $relationships['redis'][0]['port'];
  $conf['redis_client_interface'] = 'PhpRedis';
  $conf['cache_backends'][]       = 'sites/all/modules/redis/redis.autoload.inc';
  $conf['cache_default_class']    = 'Redis_Cache';
  // The 'cache_form' bin must be assigned to non-volatile storage.
  $conf['cache_class_cache_form'] = 'DrupalDatabaseCache';
}

note If you use Domain Access and Redis, ensure that your Redis settings (particularly $conf['cache_backends']) are included before the Domain Access settings.inc file - see this Drupal.org issue for more information.