Drupal Rules

The Rules module allows site administrators to define conditionally executed actions based on occurring events (known as reactive or ECA rules). It's a replacement with more features for the trigger module in core and the successor of the Drupal 5 workflow-ng module.

What is Rules

Rules features

Uses Token

Loops & Lists

Nice debug mode

Components

Scheduler

Rule structure

Condition in which cases it should react

Action - what should happen?

Events system events(s) to which one(s) rules will react

Rules Components

Reusable part of Rules

Condition set (OR/AND), action set, rule, rule set

Components evaluation can be scheduled

Can be imported

Can executed (good for debugging)

Rules Scheduler

Rules Scheduler needs components you can only schedule prepared components

Components can be scheduled as actions, for example from reaction rules

The evaluation time for scheduled tasks is set with strtotime(), which means that you can use highly flexible expressions

You can also use data selection, combined with offsets if you want to

Every scheduled task should have a unique task ID, or it will replace existing tasks

Scheduled tasks are displayed under the Schedule tab on the Rules admin pages

You can delete tasks manually if you want to

You can schedule tasks manually, without the need of reaction rules

It is sometimes useful to execute rule components manually, to see that the scheduled tasks will work as expected

Best practice

Make use of tags

Use components to organize your rules

Export your rules to feature modules using Features

Keep your rules simple

Debugging

Rules provides a very useful debugging system. This allows us to follow all the steps of a rule configuration as it's being executed.

RULES API

Events

hook_rules_event_info()

rules_invoke_event()

Actions

- hook_rules_action_info()

- Implement function [action_name](): function arguments match parameters + $settings; returns array of parameter;

Conditions

- hook_rules_condition_info()

- Implement function [condition_name](): function arguments match parameters + $settings; returns only boolean value; cant provide variables; cannot save parameters;

Other Rules API hooks

hook_rules_data_info()

hook_rules_plugin_info()

hook_rules_[action|event...]_info_alter()

hook_default_rules_configuration()

hook_rules_data_process_info()

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Useful modules

Rules link

Flag

VBO

Rules Bonus Pack

Content access

Commerce?

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