Having a problem with web workers

[thosrtanner]

I've been trying to use a web worker and I have this code:

In main window:

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let worker = new Worker("chrome://addon/content/workers/worker.js")
worker.addEventListener('message', e =>
      {
        console.log("done", e.data);
        worker.terminate();
      }, false);
worker.postMessage('5000')

and worker.js contains

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addEventListener('message', e => {
/**/console.log('Message received from main script', e)
  setTimeout(() => {
/**/console.log('Posting message back to main script')
    postMessage(12345);
  }, 2000);
});

but this is what I get in the log

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17:27:26.306 "Message received from main script" "[object MessageEvent]" worker.js:50:4
17:27:28.431 "Posting message back to main script" worker.js:52:4
17:27:28.665 "done" 12345 main.js:900

How am I meant to access the information from the main script?

Also, in passing, if I set the actual timeout to anything much over 2 seconds, the timeout doesn't expire

[JustOff]

Try something like this:

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addEventListener('message', e => {
/**/console.log('Message received from main script', e)
  let postMessageLocal = postMessage;
  setTimeout(() => {
/**/console.log('Posting message back to main script')
    postMessageLocal(12345);
  }, 2000);
});

[thosrtanner]

Sadly, that doesn't fix either of my problems -

* The parameter to the message event handler appears to be the string "[object MessageEvent]" rather than the actual message event
* If the timeout is too large, it never fires

[JustOff]

* The parameter to the message event handler appears to be the string "[object MessageEvent]" rather than the actual message event

"[object MessageEvent]" is not a string, try to print e.data and see.

* If the timeout is too large, it never fires

Does it work without setTimeout? Have you tried postMessage('12345')?

PS: Actually I don't have much experience with workers, so these are rather general considerations.

[thosrtanner]

* The parameter to the message event handler appears to be the string "[object MessageEvent]" rather than the actual message event

"[object MessageEvent]" is not a string, try to print e.data and see.

That's just evil

* If the timeout is too large, it never fires

Does it work without setTimeout? Have you tried postMessage('12345')?

PS: Actually I don't have much experience with workers, so these are rather general considerations.

And as soon as I sort that problem with e.data, out it decides to work properly >.<

Anyway, many thanks for the help.

[JustOff]

I'm glad it helped you