How async Workflow Callback can communicate result?

Community Support
,
1

Been looking into Temporal for fast few days, looking for some advice

There’s HTTP request which request workflow start.

        var workflowId = "my-workflow-prefix-%s".formatted("some-unique-identifier");
        var workflowOptions = WorkflowOptions.newBuilder()
                .setWorkflowId(workflowId)
                .setTaskQueue("my-task-queue")
                .build();

        var workflow = workflowClient.newWorkflowStub(MyWorkflow.class, workflowOptions);
        var execution = WorkflowClient.start(workflow::processWorkflow, convert(jobSummary));

       return new HttpSuccessResponse( "requested to start workflow workflowID=%s runID=%s".format(execution.getWorkflowId(), execution.getRunId()))

Here is my workflow implementation

class MyWorkflowImpl implements MyWorkflow {

  ... different activity definitions ...
  OutputActivity outActivity = Workflow.newActivityStub(OutputActivity.class, MY_ACTIVITY_OPTIONS);

  public WorkflowOutput processWorkflow(WorkflowInput input){
     ..... <workflow executions>.....
   WorkflowOutput output = new WorkflowOutput(...);
   outActivity.sendResponse(output);
  }
}

When all workflow activity completes, using outActivity to notify. Workflow options have setCompletionCallbacks method. Is there any way I can add my own callback object which provides me WorkflowOutput instance.
Currently (actually proposed) the way we design whole workflow is - We have 3 Activities running on 3 different services across network. Backend Service which started workflow, only need to know once workflow completes & receive WorkflowOutput object. This object is composite object consiting all other activities output.

2

Sorry, I don’t understand the requirements.

Backend Service which started workflow, only need to know once workflow completes & receive WorkflowOutput object.

How do you expect that service to “know”? Why is your approach of having an activity that sends a response insufficient?