Changing access control level for few methods in SpanAdapter

[vj4iosdev]

What's changed in this PR?

• Changing the access control level for the below methods from internal to public in SpanAdapter

1. toProtoSpanKind()
2. toProtoSpanEvent()
3. toProtoSpanLink()
4. toStatusProto()

• One more minor change done in OtlpTraceJsonExporter i,e changing the access control for the method getExportedSpans() to public from internal. I had contributed to this earlier but we were using this file locally. Now we are upgrading to use this directly from this repo.

Why is this change required?

• We are leveraging OpenTelemetry extensively for both mobile and web in our app (nested as well).
  In some of the flows, the WebView generates the Spans and hands over the SpanData to mobile. In this case, the native side, instead of creating new Spans/ids, needs to override the SpanData with the received SpanData (containing already generated span ids.). So we need the above-mentioned methods to be public to do so. Hence opening the PR with the changes required.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Files	Coverage Δ
...penTelemetryProtocolCommon/trace/SpanAdapter.swift	99.00% <100.00%> (ø)
...etryProtocolGrpc/trace/OtlpTraceJsonExporter.swift	88.57% <100.00%> (ø)

... and 2 files with indirect coverage changes

📢 Thoughts on this report? Let us know!.

[vj4iosdev]

@nachoBonafonte @bryce-b @vvydier Please take a look whenever you get some time.

[nachoBonafonte]

It looks good to me, I completely agree with the getExportedSpans() being public, but I don't understand why you need the SpanAdapter utility functions to be public instead of modifying the SpanData and calling the default toProtoSpan()

[vj4iosdev]

It looks good to me, I completely agree with the getExportedSpans() being public, but I don't understand why you need the SpanAdapter utility functions to be public instead of modifying the SpanData and calling the default toProtoSpan()

Ok. So here is our use case. When we receive spanData from web FCI to mobile FCI, we are required not to generate the spanID, traceID, parentSpanID and span attributes but override these as received from the web.
We need to override toProtoSpan(spanData: SpanData) method in SpanAdapter in order to override the spanID, traceID, parentSpanID and span attributes but the SpanAdapter being struct we cannot mark the method toProtoSpan(spanData: SpanData) as open to enable it for the override.

So here is our code:

static func toProtoSpan(spanData: SpanData) -> Opentelemetry_Proto_Trace_V1_Span {
       
       if OverrideProtoSpan.containsOverridenAttributes(spanData: spanData) {
           // we override spanData here
           return OverrideProtoSpan.toProtoSpan(spanData: spanData)
       }

       // then the rest of the code as is..
}

And in the OverrideProtoSpan.toProtoSpan(spanData: spanData) we use the utility functions of SpanAdapter to override the traceID, spanID, parentSpanID and span attributes received from the web FCI.
Hope this clarifies.

[nachoBonafonte]

Thanks for the clarification it makes total sense now. If you think that making span adapter a class with the open method works better for you, fellow free to change it.

[vj4iosdev]

Thanks for the clarification it makes total sense now. If you think that making span adapter a class with the open method works better for you, fellow free to change it.

Thanks for the approval @nachoBonafonte .
Static declarations are implicitly 'final' so may have to make changes in many places if I do that.
So I will have this merged as of now and open a new one later.
Please merge this PR whenever you happen to see this.