Event Listeners

Introduction

Event Listeners, a Catalyst Cloud Scale component, are an event bus service that listens for the occurrences of pre-determined events and automatically executes associated Event functions, or the targeted Circuits. Event listeners are highly useful for automating the execution of a reusable custom action that needs to be linked to a particular frequently occurring event.

Catalyst Event Listeners also allow you to transport a stream of real-time data from various Catalyst components in the application, or from custom sources, to the functions that are invoked as a result. You can associate rules with an event listener and define the exact source to listen to for events, and the actions to be taken upon their occurrence.

There are three types of Catalyst Event Listeners:

1. Catalyst Component Event Listener: The Catalyst component event listener can link an event that occurred in one of your Catalyst components to the execution of a target event function or circuit. This is created by default.
2. Custom Event Listeners: You can create custom event listeners which function differently from the Catalyst component event listener. When you create a custom event listener in Catalyst, a URL is automatically generated for it. Whenever this URL is invoked by the end user, this event listener triggers the execution of the target event function or circuit.
3. Zoho Events: You can also create Zoho event listeners that listen for and capture events occurring in other Zoho services that you have configured, such as Zoho CRM. These event listeners will get invoked every time a specific, associated event in the external service occurs, and Catalyst will execute the target event function or circuit as a result.

You can access and configure event listeners for your project from the Catalyst console. The console also provides statistics on the performance of each of your event listeners, details of queued events, and drilled-down execution history for every rule of an event listener. You can also see a sample pattern of the data that will be sent to the target function or circuit for every rule.

Catalyst also provides you with the flexibility to create application alerts for event listeners directly from the Event Listeners’ Rules section in the console, instead of navigating to the Application Alerts component.