Events

Documentation status: reference — see Maturity and evidence.

An event represents an observable change in the model or its execution. It decouples the production of a fact from the reactions to it.

Relationship with actions

An action expresses an intention to act; an event expresses that a change or observable fact occurred. An action may emit an event, and an event may trigger a reaction, a view update, or a process step.

Scope

Depending on the model and configuration, an event can be:

• local to the Runtime;
• propagated between components;
• bridged to a message to cross a process or node boundary.

Design rule

Name an event after an observable fact (TaskCompleted, InvoiceApproved) rather than a technical mechanism (SendHttpMessage).