Empty object errors?

[derekchiang]

Description

I have an event listener that looks like the following:

myQueue.on('error', (err) => {
  console.error(err)
})

However, lately I'm getting a lot of error messages where it simply prints the empty object {}.

Does this suggest that something in my code is throwing an empty object? Or is this a bug in bull?

Bull version

3.9.1

[manast]

Impossible to say actually without some kind of code that reproduces the issue, but If I have to guess I would say that you are throwing an empty object as error somewhere.

[humphd]

I'm hitting something similar with the failed event.

My code is doing this. First, my processor function looks like this:

async process function(job) {
  const { url } = job.data;
  try {
    const posts = await feedparser(url);
    return await Promise.all(posts.map(processPost));
  } catch (err) {
    const message = `Unable to process feed ${url} for job ${job.id}`;
    logger.error({ err }, message);
    throw new Error(message);
  }
};

I'm catching and constructing a new Error object, because I originally wondered if the err wasn't a real Error and that was the problem. It doesn't seem to be.

Here's my error event handler:

queue.on('failed', (job, err) => {
  log.error(`Job ${job.id} failed:`, err);
});

And a sample of my error logs for a failed job, first showing the actual error happening in the processor, and then the failed event I get:

[ 2019-12-04 09:38:21.587 ] ERROR (43628 on brightness.local): Unable to process feed http://processingjs.org/blog/?feed=rss2 for job 720
    err: {
      "type": "Error",
      "message": "Not a feed",
      "stack":
          Error: Not a feed
              at FeedParser.handleEnd (/Users/humphd/repos/telescope/node_modules/feedparser/lib/feedparser/index.js:120:13)
              at SAXStream.emit (events.js:210:5)
              at SAXParser.SAXStream._parser.onend (/Users/humphd/repos/telescope/node_modules/sax/lib/sax.js:190:10)
              at emit (/Users/humphd/repos/telescope/node_modules/sax/lib/sax.js:624:35)
              at end (/Users/humphd/repos/telescope/node_modules/sax/lib/sax.js:667:5)
              at SAXParser.end (/Users/humphd/repos/telescope/node_modules/sax/lib/sax.js:154:24)
              at SAXStream.end (/Users/humphd/repos/telescope/node_modules/sax/lib/sax.js:248:18)
              at FeedParser._flush (/Users/humphd/repos/telescope/node_modules/feedparser/lib/feedparser/index.js:1128:17)
              at FeedParser.prefinish (/Users/humphd/repos/telescope/node_modules/readable-stream/lib/_stream_transform.js:138:10)
              at FeedParser.emit (events.js:210:5)
    }
[ 2019-12-04 09:38:21.588 ] ERROR (43628 on brightness.local): Job 720 failed: {}
    module: "queue:feed-queue"

[humphd]

Just saw a failed that did have some info:

[ 2019-12-04 14:36:00.989 ] ERROR (45000 on brightness.local): Job 2548 failed: {"errno":"ENETUNREACH","code":"ENETUNREACH","syscall":"connect","address":"206.248.171.116","port":80}
...
[ 2019-12-04 14:36:04.969 ] ERROR (45000 on brightness.local): Job 2560 failed: {"code":"CERT_HAS_EXPIRED"}

So some error objects get through. Not sure why all don't.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.