External signalactivity triggers a workflow when some conditions are successfully met in another workflow or from a REST API call.
Context of use
External signalactivity is used to organize and orchestrate different processes that are part of the same customer journey into different workflows. It allows to start one workflow from another, enabling to support more complex customer journeys, while being able to better monitor and react in case of issue.
External signalactivity is designed to be placed as the first activity of a workflow. It can be triggered from the
Endactivity of another workflow or from a REST API call (for more on this, refer to the API documentation ).
When triggered, external parameters can be defined and be available in the workflow events variables. The process to call a workflow with external parameters is detailed in this section .
The activity cannot be triggered more often than every 10 minutes.
Note that an
External signalactivity can be triggered from several different events. In that case, the
External signalis triggered as soon as one of the source workflows or API call is executed. It does not require that all source workflows are finished.
When configuring an external signal, it is important to first configure the
External signalactivity in the destination workflow. Once this configuration is done, the
External signalactivity of this workflow becomes available to configure the
Endactivity of the source workflow.
- Drag and drop anExternal signalactivity into your destination workflow.
- Select the activity, then open it using the button from the quick actions that appear.
- Edit the label of the activity. This label is needed when configuring the source workflow that triggers theExternal signal.If you want to call the workflow with parameters, use theParametersarea to declare them. For more on this, refer to this section .
- Confirm the configuration of your activity, add any other activity you need and save your workflow.If you want to trigger the destination workflow from another workflow, proceed with the following steps. If you want to trigger the destination workflow from a REST API call, consult the API documentation to get more details.
- Open the source workflow and select anEndactivity. If there is noEndactivity available, add one after the last activity of a branch of the workflow.Some activities do not have any outbound transition by default. From thePropertiestab of these activities, you can add an outbound transition.For example, in anUpdate dataactivity, go to theTransitionstab and check theAdd an outbound transition without the populationoption. This option allows to add a transition that does not contain any data and do not consume any unnecessary space on your system. It is just used to connect the extraEndactivity that triggers the destination workflow.
- In theExternal signaltab of theEndactivity, select the destination workflow as well as theExternal signalactivity to trigger within that workflow.When you set anEndactivity to trigger another workflow, its icon is updated with an additional signal symbol.If you want to call the workflow with parameters, use theParameters and valuesarea. For more on this, refer to this section .
- Save the source workflow.
Endactivity of the source workflow or the REST API call is executed, the destination workflow is automatically triggered from the
The destination workflow must be started manually before it can be triggered. When started, the
External activityis activated and waits for the signal from the source workflow.
The following example illustrates the
External signalactivity in a typical use case. A data import is performed in a source workflow. Once the import is done and the database updated, a second workflow is triggered. This second workflow is used to update an aggregate on the imported data.
The source workflow is presented as follows:
- For example:tcode;tdate;customer;product;tamount aze123;21/05/2015;email@example.com;A2;799 aze124;28/05/2015;firstname.lastname@example.org;A7;8 aze125;31/07/2015;email@example.com;A7;8 aze126;14/12/2015;firstname.lastname@example.org;A10;4 aze127;02/01/2016;email@example.com;A3;79 aze128;04/03/2016;firstname.lastname@example.org;A8;149
- AnEndactivity triggers the destination workflow, which is used to update aggregates.
The destination workflow is presented as follows:
- AnExternal signalactivity waits for the source workflow to be successfully finished.