Canvas Item Decorator For Asynchronous Workflow Item

[Michaelpalacce]

Description

We want to support the possibility to define an "Asynchronous Element" with a decorator

The Async Element can be used to execute a "Workflow" asynchronously, giving you back a workflow execution token that can be used to wait for the workflow to complete and consequently extract state/outputs from it.

Example

This is how the workflow-item looks like when we are dealing with an "Asynchronous Element":

  <workflow-item name="item3" out-name="item0" type="task" launched-workflow-id="9e4503db-cbaa-435a-9fad-144409c08df0">
    <display-name><![CDATA[Other Workflow]]></display-name>
    <script encoded="false"><![CDATA[//Auto generated script, cannot be modified !
var workflowToLaunch = Server.getWorkflowWithId("9e4503db-cbaa-435a-9fad-144409c08df0");
if (workflowToLaunch == null) {
	throw "Workflow not found";
}

var workflowParameters = new Properties();
workflowParameters.put("first",first);
workflowParameters.put("second",second);
wfToken = workflowToLaunch.execute(workflowParameters);
]]></script>
    <in-binding>
      <bind name="first" type="number" export-name="first"/>
      <bind name="second" type="number" export-name="second"/>
    </in-binding>
    <out-binding>
      <bind name="wfToken" type="WorkflowToken" export-name="wfToken"/>
    </out-binding>
    <description><![CDATA[Start an asynchronous workflow.]]></description>
    <position y="60.0" x="300.0"/>
  </workflow-item>

Notes

• The auto generated code is actually needed, but we can do it in a different manner as long as it actually starts a workflow with the given parameters.
  • This will require a separate SourceFilePrinter to handle this case.
  • You can use the ts.factory to generate the code block.
• launched-workflow-id needs to be set as well, so the item looks correct in the canvas

[akantchev]

PR with implementation: #354