Event System
The Event System handles events that occur in Content Manager. It is part of the TOM.NET API. The Event System lets you write event handlers and hook each one up to a specific type of event occurring in the Content Manager, such as an item being saved. Because the events are organized in a hierarchy, you can catch multiple events using the same event handler.
| Subject type | The subjects are the Content Manager content items (such as Components or Pages). |
| Event type | The event is the specific action taking place (such as saving or deleting). |
| Phase | The timing on or around the action (before or after). |
This setup allows you to subscribe (synchronously or asynchronously) to a specific subject type, event type or phase, or to any combination of these three. The latter option makes it possible to, for example, add functionality which will be triggered when a Component or a Page is saved, from a single line of code.
In addition to using the Event System for automation (say, by responding to the creation of a Component by creating a new Page, adding the Component to it, and publishing the Page), you can also use it to create audit trail logs. The modular nature of the Event System implementation lets you add multiple Event Systems to a single SDL Tridion Sites instance, each having its own specific function and sequential position in the process.