What is a Signal?

Understand what a Signal is and how ProcessMaker Platform has extended standard BPMN 2.0 Signals with webhooks.

BPMN 2.0 Signals

Signals communicate information from one isolated Process model element to another. Signals are part of the BPMN 2.0 specification to broadcast or receive data from a broadcast across Processes, and/or Pools within the same Process model. Similar to radio broadcasting, one Signal-type element designed to broadcast Request data broadcasts that data, while another Signal-type element designed to listen for that Signal from a potentially isolated Process model element receives none, all, or part of that Request data from the broadcasting element.

These are throwing Signal-type elements that broadcast Request data:

• Intermediate Signal Throw Event element

• Signal End Event element

These are catching Signal-type elements that listen for a broadcasting Signal to receive part of or its complete Request data:

• Signal Start Event element

• Intermediate Signal Catch Event element

• Boundary Signal Event element

Signal Manager contains all Signals regardless of whether they are used for broadcasting or listening BPMN elements. Signal-type Process model elements may then subscribe (or use) that Signal.

Collection Signals

The Collections package must be installed.

Each Collection has three Signals that may independently be enabled or disabled to broadcast its Signal when each occurrence of the following functions in that Collection:

• Create a Collection record: A new Collection record is created.

• Edit a Collection record: A Collection record is edited.

• Delete a Collection record: A Collection record is deleted.

Each Collection's Signals are created and display in Signal Manager when that Collection is created.

Any Signal-type Process model element that subscribes to (uses) a Collection Signal listens for when one of these Collection Record events occur. For example, a Signal Start Event element may listen for when a record in the Collection associated with that Signal is created.

Manage Collection Signals from Signal Manager.

User Signals

The Advanced Users package must be installed.

User Signals broadcast information pertaining to four user-type events. User Signals may be enabled or disabled independently of one another. Follow these steps to use a User Signal:

1. Create a Signal in Signal Manager. In the Signal ID setting for the new Signal, use the Signal ID value for the corresponding user-type event from the following table. For example, to create a Signal that triggers each time a new user account is created, enter user_create in its Signal ID setting.

2. Enable the toggle key for that user-type event. If that user-type event's toggle key is not enabled when that Signal is to trigger, that Signal does not trigger. Administrators may control when these user-type events may occur regardless of how Process Designers implement those Signals in Process models.

Any Signal-type Process model element that subscribes to (uses) a User Signal listens for when one of these user-type events occur. For example, a Signal Start Event element may listen for when a new user is created to start a Request that requisitions equipment for that user. Similarly, use a "Delete" User Signal to start a Request that offboards the deleted user's access from organizational applications, infrastructure, and resources.

Below is a description of each user-type event and the Signal ID value to use for its corresponding Signal.

User-Type Event	Description of Event	Signal ID
Create	A new user account is created.	user_create
Delete	A user account is deleted.	user_update
Read	A user account is accessed in either of the following ways: A user account is viewed. A user profile is viewed.	user_read
Update	A user account is edited.	user_delete

When a User Signal event triggers, the following occurs:

• That User Signal broadcasts the _user Magic Variable containing the user account affected by that User Signal event. For example, the full name set in the affected user account is accessible with JSON dot notation as _user.fullname. See the _user Magic Variable to reference any JSON object within this Magic Variable.

• The User Signal event broadcasts any User Enhanced Properties and the affected user account's corresponding values.

Manage User Signals from the User Signals tab in Settings.

Related Topics

pageView SignalspageCreate a New SignalpageSearch for a SignalpageEdit a SignalpageDelete a SignalpageProcess Modeling Element DescriptionspageWhat is a Collection?