Fix context propagation for guava AsyncEventBus

[xiangtianyu]

resolves to #6273
AsyncEventBus can cause trace IDs to appear as "0000000000000000". The issue is resolved by removing the event bus class from the OpenTelemetry agent's ignore list, as AsyncEventBus relies on an executor that the agent already supports.

https://github.com/google/guava/blob/d7240c0eedbef92ca40377e864a77a1e30e91474/guava/src/com/google/common/eventbus/Subscriber.java#L66-L75

[laurit]

@xiangtianyu do you know whether this PR resolves #6273?

[xiangtianyu]

@xiangtianyu do you know whether this PR resolves #6273?

I build a demo like this:

public class MyNotifier {
    private static final Logger log = LoggerFactory.getLogger(MyNotifier.class);

    @Subscribe
    public void handleEvent(String event) {
        log.info("Received event: {}", event);
        log.info("traceId: {}", Span.current().getSpanContext().getTraceId());
        log.info("spanId: {}", Span.current().getSpanContext().getSpanId());
    }
}

@RequestMapping("eventbus")
    public String eventbus() {
        log.info("Posting event to EventBus");
        log.info("traceId: {}", Span.current().getSpanContext().getTraceId());
        log.info("spanId: {}", Span.current().getSpanContext().getSpanId());
        asyncEventBus.post("Hello, AsyncEventBus!");
        return "eventbus";
    }

The result of the print is like:
before allow class:

after allow class:

[xiangtianyu]

BTW, if i want to create bus event instrumentation, it should be a new independent instrumentation "guava-eventbus" or a part of guava instrumentation?

[laurit]

BTW, if i want to create bus event instrumentation, it should be a new independent instrumentation "guava-eventbus" or a part of guava instrumentation?

I'd add it under the guava instrumentation.

[laurit]

would it be possible to add a regression test for this?

[xiangtianyu]

would it be possible to add a regression test for this?

I don't know what to do. Add a test for eventbus in guava instrumentation? Or any other ways?

[otelbot-java-instrumentation]

🔧 The result from spotlessApply was committed to the PR branch.

[xiangtianyu]

I tried to add a test for this case in guava instrumentation

[otelbot]

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