Exporter shutdown method does not flush spans when wrapped with SimpleSpanProcessor

[chasestarr]

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What happened?

Steps to Reproduce

When I end a span, then next call shutdown, the ended span is not flushed. If I wait for the next event loop tick, the span is flushed as-expected. See this example in the repo that demonstrates the problem and an example work-around.

parentSpan.end();
// give some time before it is closed
setTimeout(() => {
  // flush and close the connection.
  exporter.shutdown();
}, 2000);

Providing 0 to setTimeout also resolved the issue for me.

parentSpan.end();
setTimeout(() => {
  exporter.shutdown();
}, 0);

Additional Details

See this other comment where the issue is shared.

Ideally, updating the example to below would work without the event loop wait.

parentSpan.end();
exporter.shutdown();

OpenTelemetry Setup Code

package.json

Relevant log output

Operating System and Version

No response

Runtime and Version

No response

[pichlermarc]

Hi @chasestarr thanks for reaching out.

I see that the example there is misleading. Shutting down the exporter does not flush data from the SDK, it only shuts down the exporter itself. There is a NodeTracerProvider#shutdown() method that can be called that will also flush data, that's the one we want to show in the example.

I'll open a PR to update the example.