Content Hub

Syndicating configuration with Content Hub


Content Hub 2.x will reach end-of-life on December 31, 2024. Acquia recommends that you update your Content Hub version to Content Hub 3.x by using the composer require instructions available on the acquia_contenthub project page.

When exporting content from a publisher, Content Hub calculates all dependencies for accurate reproduction on a subscriber. The export includes content dependencies such as entity references and media. It also includes Drupal configuration entities required to reproduce that content on a subscriber.

What are configuration entities?

A configuration entity represents the information that your site contains apart from the content. It includes name of the site, content types, and views that you have defined. For more information about configuration entities, see Configuration Entity.

Configuration entities are exported by the publisher to the Content Hub service, and can be imported into subscribers.

Configuration entities are exported as dependencies of content entities. For example, when exporting a blog post, Content Hub also exports the content type of the blog post to create the content type if it is missing on the subscriber.

Viewing exported configuration entities

To view all exported configuration entities, run the following Drush command on your publisher:

drush ach-list --type=drupal8_config_entity

Disabling configuration syndication

  • Configuration syndication can only be disabled on publishers with Content Hub 3.4.0 or later.
  • When you exclude configuration entities from export, Content Hub cannot identify the changes on subscribers. This might result into import failure because of mismatch between the configuration on subscribers and the structure of the exported content.

In certain scenarios, you may want to prevent Content Hub from changing configuration entities on subscriber sites. For example, you might be managing your configuration with a different process. To achieve this, publishers can exclude configuration entities from export.

When a publisher exports an entity, it must calculate the dependencies of that entity. For example, when a blog post is exported, the dependencies include the configuration of the Blog content type and any fields attached to it. The dependencies are listed in the Common Data Format (CDF) document, which the publisher exports. Each document is stored in the Content Hub service. Subscribers use this document to import the necessary dependencies.

If configuration syndication is disabled on a publisher, the configuration entities are excluded from the dependency list in the exported CDF document, and that list only includes the available content entities.

To exclude configuration entities from export:

  1. Navigate to the Content Hub settings admin page.
  2. Click the Exclude from export queue tab.
  3. Slide the Exclude config entities toggle bar to right to disable configuration syndication.

  4. Save the changes.

Important considerations when disabling configuration syndication

  • Do a full purge when enabling or disabling configuration syndication. When configuration syndication is disabled, configuration entities are not exported from the publisher. However, older content entities within the Content Hub service might still reference configuration entities as dependencies. A full purge eliminates the outdated entities, which can be re-exported by the publisher.
  • Establish an alternative process to ensure synchronization between subscriber and publisher configurations before disabling configuration syndication. Any inconsistencies can result in unexpected behavior during imports.
  • Avoid a hybrid approach where some publishers export configuration while others do not. This behavior is controlled per publisher. Consider a hybrid approach only if you have an effective strategy for managing whether an import may include configuration entities as dependencies.