event_pipeline

Event Pipeline provides a flexible, plugin-based system for propagating data changes from your Drupal site to external and internal services. Site builders create named pipelines through a configuration UI, attach pluggable process handlers, and trigger them programmatically whenever a value changes. Whether you need to sync user email updates to Auth0, push order data to Shopify, or log field changes for auditing, Event Pipeline gives you a reusable framework so you don't have to write one-off integration code for every external system.

Features

Named pipelines — Create as many pipelines as you need, each with its own label, description, and set of process handlers. For example, a "User email sync" pipeline that fans out email address changes to multiple services.
Plugin-based process handlers — Each step in a pipeline is a Drupal plugin. Enable bundled plugins (Auth0, Shopify) or write your own by extending a single base class. Plugins receive the new value, the old value, and an arbitrary context array.
Sequential and parallel execution — Choose whether processes run one-at-a-time (sequential) or are dispatched through Drupal's Queue API (parallel). Sequential mode isolates failures so one broken step doesn't block the rest.
Weighted ordering — Drag-and-drop process weights in the admin UI to control the order processes execute.
Secure credential storage — Plugins that call external APIs can store credentials through the Key module. If Key is not installed, a plain-text fallback is provided automatically.
Simple service API — Trigger any pipeline with two lines of code: $service->setEventPipeline('my_pipeline')->broadcastChange($new, $old, $context);
Enable/disable at every level — Toggle entire pipelines or individual processes on and off without removing configuration.

Common use cases:

Syncing user profile changes (email, name, roles) to identity providers like Auth0 or Okta.
Pushing customer or order updates to e-commerce platforms like Shopify.
Logging field-level changes to an external audit trail or analytics service.
Sending webhook notifications to third-party systems when content changes.
Fanning out a single data change to multiple downstream services in one consistent pipeline.

Post-Installation

Grant the "Administer event pipelines" permission to the appropriate roles at Administration > People > Permissions.
Navigate to Administration > Configuration > Workflow > Event Pipelines (/admin/config/workflow/pipelines).
Click "Add pipeline". Give it a label (e.g. "User email sync"), choose an execution mode (sequential or parallel), and save.
On the pipeline list, click "Manage processes" for your new pipeline.
Click "Add process", select a process plugin from the dropdown, fill in any plugin-specific configuration (API keys, log levels, etc.), set a weight, and save.
Repeat step 5 to attach as many process handlers as needed.

In your custom module code, call the pipeline service whenever the relevant data change occurs:

$service = \Drupal::service('event_pipeline.pipeline_service');
$results = $service->setEventPipeline('user_email_sync')->broadcastChange($newEmail, $oldEmail, ['entity' = $user]);

Each process returns a result array with success, message, and optional data keys, so you can inspect outcomes programmatically.

Additional Requirements

PHP 8.3 or higher.
Drupal 10 or 11.
No additional modules are required for the base module.

Submodule requirements:

Event Pipeline Auth0 requires the Auth0 and ExternalAuth modules.
Event Pipeline Shopify requires the shopify/shopify-api Composer package (installed automatically via Composer).

Recommended modules/libraries

Key — Allows process plugins to store API credentials, tokens, and secrets securely instead of in plain-text configuration. The module detects Key automatically and switches credential form elements accordingly.

Similar projects

Rules — A general-purpose event/condition/action engine. Event Pipeline is narrower in scope: it focuses specifically on broadcasting value changes through a weighted chain of process plugins, with built-in support for parallel execution and secure credential handling. If you need broad event-condition-action workflows, Rules may be a better fit. If you need a lightweight, developer-friendly way to fan out data changes to external services, Event Pipeline is purpose-built for that.
ECA — Event - Condition - Action, a no-code automation framework. Like Rules, ECA covers a wider range of automation scenarios. Event Pipeline complements ECA by providing a focused, code-first pipeline pattern for service integrations.
Hook Event Dispatcher — Converts Drupal hooks into Symfony events. This is an event-dispatching layer, not a pipeline execution framework. You could use Hook Event Dispatcher to trigger an Event Pipeline from a Symfony event subscriber.

Supporting this Module

If you find Event Pipeline useful, consider supporting its development:

Report bugs and suggest features in the issue queue.
Submit patches or merge requests on Drupal.org.
Spread the word by writing about your use case or presenting at a Drupal meetup or camp.