Problem with delta PUT or delta PUT documentation or me?

[preeve9534]

If I copy the example code from the documentation and tweak it a little I can make this test frame:

function myActionHandler(context, path, value, callback) {
   console.log(">>>>>>>>>>>>>>>>>> action handler executing");
   return { state: 'COMPLETED', statusCode: 200 };
}

plugin.start = function(options) {
  var path = "electrical.switches.bank.usb0.1.state";

  console.log(">>>>>>>>>>>>>>>> registering put handler");
  app.registerPutHandler('vessels.self', path, myActionHandler, 'somesource.1');

  var putdelta = {
     "context": "vessels.self",
     "correlationId": uuidv4(),
     "put": {
        "source": plugin.id,
        "path": path,
        "value": 1
     }
  };

  console.log(">>>>>>>>>>>>>>>> issuing put delta");
  app.handleMessage(plugin.id, putdelta);
}

And I would expect to see three console log messages, the last message being emitted by myActionHandler.

In fact the action handler seems never to be called and I just see the two messages from plugin.start. No error messages in the log.

I'm quite prepared to believe that I'm missing something or misunderstanding something. But what?

[tkurki]

put deltas are not processed in app.handleMessage, there's an (sadly undocumented) putPath(path, value, callback, source) to do puts from plugins.

But....is this just testing? Why would you put from a plugin to itself?

[preeve9534]

Just testing. Documentation around this is rather bleak and I have not been able to get anything working, so back to basics...

On Sat, 14 Nov 2020, 17:23 Teppo Kurki, notifications@github.com wrote:

put deltas are not processed in app.handleMessage, there's an (sadly undocumented) putPath(path, value, callback, source) to do puts from plugins.

But....is this just testing? Why would you put from a plugin to itself?

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[preeve9534]

Sorry to get back on this again, but I now have the test frame below.

The action handler never gets called.

(I also tried app.putSelfPath with the same result)...

function myActionHandler(context, path, value, callback) {
    console.log(">>>>>>>>>>>>>>>>>> action handler executing");
    return { state: 'COMPLETED', statusCode: 200 };
  }

  plugin.start = function(options) {
    var path = "electrical.switches.bank.usb0.1.state";

    console.log(">>>>>>>>>>>>>>>> registering put handler");
    app.registerPutHandler('vessels.self', path, myActionHandler, 'somesource.1');

    console.log(">>>>>>>>>>>>>>>> issuing put delta");
    app.putPath(path, 1, () => console.log("Cooee"), "somesource.1");
  }

[sbender9]

It could help to print out the result from app.putSelfPath

          app.putSelfPath(path, 1, res => {
            app.debug(JSON.stringify(res))
        })

[sbender9]

and just in case there's an in with sources, leave off the somesource.1 from your calls.

[tkurki]

With putPath you need the complete path from the root, including the vessels.self context. putPath returns a Promise that you can use to figure out what's happening.

    var path = "electrical.switches.bank.usb0.1.state";

    console.log(">>>>>>>>>>>>>>>> registering put handler");
    app.registerPutHandler('vessels.self', path, myActionHandler, 'foo');

    console.log(">>>>>>>>>>>>>>>> issuing put delta");
    app.putPath(`vessels.self.${path}`, 1, () => console.log("Cooee"), 'foo').then(x => console.log(x))

You can also omit the source, as mostly there is only one handler for a path.

So this was a problem related to ther server's plugin API, that is not part of the specification to be exact.