Triggers
In addition to the triggers available for general use, triggers that were originally created in Project Flogo® are supported. Such triggers are marked with an
OSS
tag on them.
It is preferable to use the general-purpose triggers (the triggers that do not have an
OSS
tag on them) as they have richer functionality.
For more information on the triggers that are marked with an
OSS
tag, see
https://github.com/project-flogo/contrib.
Trigger configuration fields are grouped into Trigger Settings and Handler Settings. A single trigger can be associated with multiple handlers.
- Trigger Settings - these settings are common to the trigger across all flows that use that trigger. When Trigger Settings are changed, the change applies to all flows that are attached to the trigger. A warning message is displayed asking you to confirm the changes before they are committed.
- Handler Settings - these settings apply to a specific flow attached to the trigger. Hence, each flow can set its values for the Handler Settings fields in the trigger. To do so, open the flow and click the trigger to open its configuration dialog. Click the Settings tab and edit the fields in the Handler Settings section.
- You cannot create a flow branch from a trigger.
- You can create the trigger at the time of flow creation or create a blank flow to begin with and attach the flow to one or more triggers later after the flow has been created. If you anticipate that you might need to attach the flow to multiple triggers, be sure to create a blank flow and attach it to the triggers as needed.
For triggers that have an output, the output from the trigger becomes the input to the flow. Likewise, the output from the flow becomes the reply from the trigger.
When using the Lambda, S3, or Gateway triggers, keep the following in mind:
- You can only have one trigger. The Lambda trigger supports only one handler per trigger, it can have only one flow attached to it. The S3 and Gateway triggers support multiple handlers (flows), so you can have multiple flows in the app that are attached to the same S3 or Gateway trigger.
- An app that has one of these triggers cannot contain any other trigger.
- You can also have blank flows in the app, which can serve as subflows for the flows that are attached to one of these triggers.