Event Hooks

Event hooks allow you to extend Obsidian's event notifications to support things like instant messaging, customized logging, etc. This feature was introduced in version 4.5.0.

EventHook Interface

EventHook Javadoc

Note: If you need to set up a development environment to create Obsidian event hooks, see the Classpath section.

Implementing custom notifications in Obsidian is as simple as implementing a single interface and calling a method to register it with the scheduler.

The interface you need to implement is the following.

public interface EventHook {
    public abstract void dispatch(Event event) throws Exception;
}

The dispatch() method gets called with every logging/notification event Obsidian encounters. The implementor is responsible for filtering out appropriate events to respond to, and what occurs when an applicable event is encountered. As an example, we've provided a reference implementation of a Slack notifier, and its source code is available in the Obsidian distribution.

After creating an instance of a class that implements EventHook, you simply need to register it with Obsidian. The example below shows our reference implementation which posts notifications to a Slack channel by using incoming web hooks.

    EventHook customNotifier = new SlackEventHook("Obsidian Scheduler", "https://hooks.slack.com/services/XXXXXXX/YYYYYYYY/ZZZZZZZZZZ", SlackEventHook.DEFAULT_LEVELS, SlackEventHook.Default_CATEGORIES);
    eventHooks.register(customNotifier); // we will now get notifications in slack for any FATAL, ERROR or WARN events