After some hard work, the workflow-ng API is ready.
It features
- actions, which may be configurable
- conditions, which may also be configurable
- support for multiple arguments, for actions as well as for conditions
- condition evaluation with logical operations like OR, AND and NOR
- events, for which conditions and actions can be configured. They may be contributed by modules.
- dynamic loading of needed arguments
- ordered conditions and actions - they are evaluated like they are ordered
- form API style configuration and processing of conditions and actions
So workflow-ng works event based. (And no, I'm not talking of calendars ;)
E.g. workflow-ng defines some basic events for drupal core, like 'node update, 'node insert', 'user update' and so on. So this are the events you can react on by defining conditions and actions for them.
What makes workflow-ng powerful is, is it's flexible handling of arguments. Each of these events has to define a list of available arguments. Then any conditions and actions, that can work with these arguments, can be configured for this event. So an action can be used in any situation, where the suitable arguments are available. There is no need for the action, to be coded aware of every event.. :)
As modules may define further events, this enables module authors, to easily allow site administrators to customize the behavior by just defining some further events.
Read more at http://more.zites.net/workflow-ng-api-ready