Hello all

I recently found this post back from awhile ago. https://answers.laserfiche.com/questions/70701/REST-API--Workflow-Web-Service

In the post, the Laserfiche Developer makes mention of two "hidden parameters" that exist in Workflow and they can be passed when starting a Workflow. These two Hidden Parameters are $SyncWebAddress and $SyncMethod.

We were able to utilize these parameters and make a webhook in PHP that gets a response back from a workflow. This response also contains output parameters that the developer can set in workflow. The response comes in XML.

So one can pass $SyncWebAddress = "URL of webhook" and $SyncMethod = "WebService" and have the Workflow POST to a Webhook. This examples just writes the response to a JSON file, but obviously other methods could be used.

<?php
    $headerStringValue = $_SERVER["HTTP_LFWF_INSTANCE_ID"];
    $fileName = "$headerStringValue.json";

    $data = file_get_contents("php://input");

    $xml = simplexml_load_string($data, "SimpleXMLElement", LIBXML_NOCDATA);
    $json = json_encode($xml, JSON_PRETTY_PRINT);

    file_put_contents($fileName, $json);

With the output file consisting of

{
    "Parameter": {
        "@attributes": {
            "Style": "Output",
            "Name": "message",
            "Multivalued": "false"
        },
        "Values": {
            "Value": "Hello World 9\/14\/2021 1:17:57 PM"
        }
    }
}

 I understand using this method there could be some concerns, long running Workflows, etc, I get all that, but I have questions surrounding hidden parameters in Workflow
 

1. What other hidden Parameters exist when starting a Workflow with the Workflow Web Services? Right now I only have two, is there more? I can't find any documentation pertaining to them other than the one workflow answer from several years ago.
2. What OTHER SyncMethods exist? Obviously more $SyncMethods have to exist besides "WebService", otherwise SyncMethod wouldn't even be an option, I would just pass $SyncWebAddress and be done. Can I do something like
   
   $SyncMethod = File
   $SyncFilePath = "C:\PathToFileHere.xml" ?

Thanks!