put baggage as Span attribute

[flodetan]

Is your feature request related to a problem? Please describe.
Yes, I didn't find anywhere to put baggage as Span attribute

Describe the solution you'd like
My opentelemetry-java have tracecparent and baggage propagation, span data was export by otlp exporter.

I have some information propagated through baggage, I want to put baggage to Span attribute to make information be visible in jaeger UI. How can i implement this feature ?

Describe alternatives you've considered
PS : I already tried in SimpleSpanProcessor.onStart() but baggage is empty(not generated yet), and SimpleSpanProcessor.onEnd() but no context provided.
Also tried in w3cTraceContextPropagator and w3cBaggagePropagator, i can get baggage from context , but it doesn't provide dataobject to set baggage.

// SimpleSpanProcessor
  public void onStart(Context parentContext, ReadWriteSpan span) {
   // here no baggage exist in parentContext
  }

public void onEnd(ReadableSpan span) {
   // here no baggage should exist, but no context provided
 }

// W3CTraceContextPropagator
public <C> Context extract(Context context, @Nullable C carrier, TextMapGetter<C> getter) {
    if (context == null) {
      return Context.root();
    }
    if (getter == null) {
      return context;
    }
    SpanContext spanContext = extractImpl(carrier, getter);
    if (!spanContext.isValid()) {
      return context;
    }
    return context.with(Span.wrap(spanContext));
    // here I can extrace baggage from carrier, but spanContext didn't have any fields to set baggage.
}

Additional context

[jkwatson]

Take a look at the W3CBaggagePropagator. It will put baggage into the Context, and that can be seen in a SpanProcessor implementation.

[trask]

@whughchen also check out open-telemetry/opentelemetry-java-instrumentation#8023

[flodetan]

Take a look at the W3CBaggagePropagator. It will put baggage into the Context, and that can be seen in a SpanProcessor implementation.

the problem is that in SpanProcessor.onStart() method baggage is empty(haven't generated/propagated yet), and SimpleSpanProcessor.onEnd() method no context provided.

[jkwatson]

Well, there are several things here, so let's keep them separate:

1. Putting some baggage into the context, and making that context the current context.
2. Getting the baggage out of the current context and adding some baggage item as a span attribute.
3. Propagating baggage in & out of your process using the provided W3CBaggagePropagator

Have you been able to do any of these three things successfully? Do you have some working code you can share with what you're trying?

[github-actions]

This issue was marked stale due to lack of author feedback. It will be closed in 7 days.

[github-actions]

Closed as inactive. Feel free to reopen if this issue is still being worked on.

[mukutbhattacharjee]

@flodetan were you able to find a solution for this?

[flodetan]

@flodetan were you able to find a solution for this?
@mukutbhattacharjee yes, see above : #5320