Expose OpenTelemetry span and trace ID

[devgianlu]

Goal

Expose an API to access the OpenTelemetry trace and span IDs. This allows greater flexibility when integrating with custom observability components. For example, this allows us to create traceparent headers for distributed tracing.

Testing

Not much to test.

[bidetofevil]

Hi @devgianlu - thanks for your contribution!

If you are looking for the traceId from the Android SDK, you can get it via an attribute on the EmbraceSpan object that is returned, so I suspect you are trying to use it through one of our other SDKs, like Unity or Flutter?

If that's the case, the idea is to expose it through that, as those SDKs should have access to that information already.

Or do you really need to look up a traceId based solely on the spanId no other references?

[devgianlu]

You are correct, the work is mainly focused on getting access to trace and span IDs from the Flutter SDK. The complementary work can be found here (iOS only, no Android).

While for iOS I was able to get them directly without changing the platform specific SDK, I was not able to do so for Android thus the addition of these accessors, but I might have missed something.