Start Span from callback, finish from another

[ThHareau]

Hi,

I'm trying to track performance for graphile worker in node js.

The nicest way would be to hook into the events emitter that gets configured with graphile:

const events: WorkerEvents = new EventEmitter();

events.on('job:start', () => {
  Sentry.startSpanManual({ op: 'queue.start' }, () => { /* Nothing? */})
  console.debug({ activeSpan: Sentry.getActiveSpan() });
});

events.on('job:complete', () => {
  Sentry.getActiveSpan()?.end();
});

However, the transaction doesn't seems to exist, the log activeSpan is empty, and no transaction is created on Sentry.

Sentry is configured correctly as I see child spans in the UI, they are not attached to any parent span tho.

[lforst]

To get this working I recommend using startInactiveSpan, to get a span instance, then wrap your event handler code in withActiveSpan(span, () => { ... }).

Additionally, you will have to store the span instance somewhere to be able to finish it from the other event handler. You could use a WeakMap or pass the events a shared reference that they can write the span to and read the span off of.

[ThHareau]

Ok I'll do so.

Is there not a way to set an inactive span as active? I was hoping to be able to hide sentry's implementation details from the tasks themselves, to reduce the code complexity.

[lforst]

Is there not a way to set an inactive span as active?

withActiveSpan will do exactly that!