Throwing Workflow Events

info

Before you can add a THROW_EVENT Node to a WfSpec, you need to create a WorkflowEventDef metadata object in LittleHorse representing the event you want to throw. You can do that following our metadata management docs.

To throw a WorkflowEvent in LittleHorse, you must define a THROW_EVENT Node in a WfSpec.

Defining a THROW_EVENT Node

The following code defines a workflow that waits 5 seconds before throwing a WorkflowEvent named "my-event", with the content "Hello There!".

Java

public static Workflow getWorkflow() {
    return Workflow.newWorkflow(
        "throw-wf-event",
        wf -> {
            wf.sleepSeconds(5);
            wf.throwEvent("my-event", "Hello There!");
        });
}

Python

def get_workflow() -> Workflow:
    def my_entrypoint(wf: WorkflowThread) -> None:
        wf.sleep(5)
        wf.throwEvent("sleep-done", "Hello There!")

    return Workflow("throw-wf-event", my_entrypoint)

Go

func ThrowWfEvent(wf *littlehorse.WorkflowThread) {
  wf.Sleep(5)
  wf.ThrowEvent("my-event", "Hello there!")
}

Required Parameters

The two required values are:

1. workflowEventDefName is the Name of the WorkflowEventDef that you want to throw a WorkflowEvent for.
2. content is the content of the WorkflowEvent that will be stored in the content field of the WorkflowEvent. Content type will match the VariableType specified in your WorkflowEventDef.