Queued Events

As described in the Terminology section, when an event for which an event listener rule has been configured has occurred, the event will be queued for processing. The event will be added to a queue particular to that event listener. This can be an event in a component that an event listener has been configured to listen to, or the invocation of a custom event listener’s URL.

The process can be described as follows

Event listener listens for a component or a custom event
Event Occurs
Event is pushed to queued events
Event listener’s rule is triggered
The rule invokes the associated event functions or circuits and passes the event data for execution
Event function or target circuit executes
Function or circuit execution is a success or a failure
Event is removed from the queue, and is categorized as a processed or failed event

Queued Events in Component Event Listeners

You can view the events that are currently in the queue at any point of time, from the Queued Events section in the Event Listeners page. The event listener’s tile will also display the number of events that are in the queue currently, in its statistics.

queued_events_highligt_queued

The queued events section displays various details of the events such as their time of initiation, source, action, and the data in JSON format that will be passed to the associated event functions or circuits by the rules respectively. You can view the formatted data by clicking the Format JSON button.

queued_events_show_queue

You can filter the queued events displayed on this page based on specific components using the first drop-down list. You can also use the search bar to search for events based on event time, rule name, action or even component name. For more precise search results, you can search using keywords from the event data.

queued_events_component_filter

You can further narrow the list of queued events by filtering based on the specific actions pertaining to each component.

catalyst_event_listener_component

You can also filter the events based on their time of initiation, such as from the last 15 minutes or 30 minutes from the time-based drop-down list.

queued_events_time_filter

Queued Events in Custom Event Listeners

Similar to the queued events in the component event listener, you can view the events queued for processing in a custom event listener by clicking Queued Events from a custom event listener’s page.

The page will display details like the date the custom event listener was created on, the description and by whom it was created. Additionally, you will be able to view and copy the Produce URL of the custom event.

catalyst_event_listener_custom_view

The queued events section also displays other details of the events such as their, source, action, and the event data in the JSON format that will be passed to the associated event functions or circuits by the rules respectively. You can view the formatted data by clicking the Format JSON button.

catalyst_event_listener_custom_queue_view

As in Component Event Listeners, you can filter and search the queue for events.

You can click Refresh to view an updated list, if there are any lags in displaying the events.

After these events are processed, they will be removed from the queue.

Pause Events in Queue

Catalyst enables you to pause any event in the queue for a maximum period of five minutes in one go. Pausing a queue allows you to stop its processing temporarily and perform code fixes in case any errors occur.

You can then either manually resume a paused queue or wait for the queue to be resumed automatically when the five-minute timer runs out.

queued_events_timer_visible

You can pause the queue by clicking the Pause Queue button in the right-hand corner.
Click Yes, Proceed

You can search and filter results in the queue even while it is paused. The time remaining for the queue to automatically resume will be displayed on top of the Queued Events page.

queued_events_search_sort_queue

Remove Events from Queue

While the queue is paused, you can delete events from the queue. This will remove them permanently from the queue and terminate their processing. If an associated event function or circuit has been triggered, it will also be terminated immediately.

To remove one or more events from the queue:

Select an event or multiple events when the queue is paused using the check box, then click Remove Event.

You can also select all events and delete them in bulk. Click Remove All.
Click Yes, Proceed to confirm.

Resume Queue

To manually resume a paused queue:

Click Resume Queue.
Click Yes, Proceed to confirm.

Note: After a queue has been resumed, it can only be paused again after 15 minutes.

Kill Events in Queue

A particular event in a queue that is currently being processed will be displayed in the In Progress section of the event listener’s index page. This section will display the event’s details such as the rule name, Execution ID, date and time of processing, and the event data in the JSON format.

When you kill an event from the In Progress section it will be terminated abruptly and will be removed from the queue. The executions of its associated functions or circuits will also be terminated immediately.

queued_events_show_inprogress

To kill an event in progress:

Click the kill icon from the right-hand corner of the In Progress section.
Click Yes, Proceed to confirm.

Disable the Queue of an Event Listener

When an Event Listener is created, Catalyst automatically creates and enables a queue for the processing the events associated with that event listener. You can disable this queue when you don’t want any events in that queue to be processed. You can always enable the queue again when you require.

Click the ellipsis icon in the top right-hand corner of the component event listener or a custom event listener’s page, and click Disable Queue.
Click Yes, Proceed to confirm.