Does "handled correctly" mean crash the app? (no, seriously)

[paulgrieselhuber]

Our app crashes and restarts every time an error is intentionally in a queue.process when running code approximating this:

// Setup the message queue
const connection = {
  redis: { host: process.env.REDIS_HOST },
};

const queue = new Bull("theJob", connection);

queue.process(async (job, done) => {
  const { data: body } = job;

  console.log("Doing some work...");

  let theThing;
  
  // Load the thing from the db
  try {
    theThing = await loadTheThing(body);
  } catch (error) {
    throw new Error("Some error happened", error); // always causes app to crash / restart
  }

  // Return successfully
  done();
});

const handleTheJob = async (ctx) => {
  const { request } = ctx;
  const { body } = request;

  // Add the thing to the processing queue
  await queue.add(body, { attempts: 3 });

  // We can now return success
  ctx.body = { success: true };
};

export default handleTheJob;

From the docs it looks like we're doing things properly:

imageQueue.process(function (job, done) {
  // transcode image asynchronously and report progress
  job.progress(42);

  // call done when finished
  done();

  // or give a error if error
  done(new Error('error transcoding'));

  // or pass it a result
  done(null, { width: 1280, height: 720 /* etc... */ });

  // If the job throws an unhandled exception it is also handled correctly
  throw new Error('some unexpected error');
});

But it occurs to me - what does "handled correctly" mean? I assumed this mean something more like "will tell Bull to retry according to attempts, etc., not crash the entire application.

What am I missing?

[manast]

You are using the "done" callback and async, you must use one or the other, not both. I recommend you to use async only.

[paulgrieselhuber]

Ah, fantastic. Thanks @manast.