Add response upstreamId to span (#203)

src/main/kotlin/io/emeraldpay/dshackle/commons/constatnts.kt

@@ -7,6 +7,7 @@ const val SPAN_STATUS_MESSAGE = "status.message"
 const val SPAN_READER_RESULT = "reader.result"
 const val SPAN_REQUEST_API_TYPE = "request.api.type"
 const val SPAN_REQUEST_UPSTREAM_ID = "request.upstreamId"
+const val SPAN_RESPONSE_UPSTREAM_ID = "response.upstreamId"
 const val SPAN_REQUEST_ID = "request.id"
 
 const val LOCAL_READER = "localReader"

src/main/kotlin/io/emeraldpay/dshackle/rpc/NativeCall.kt

@@ -27,6 +27,7 @@ import io.emeraldpay.dshackle.commons.LOCAL_READER
 import io.emeraldpay.dshackle.commons.REMOTE_QUORUM_RPC_READER
 import io.emeraldpay.dshackle.commons.SPAN_ERROR
 import io.emeraldpay.dshackle.commons.SPAN_REQUEST_ID
+import io.emeraldpay.dshackle.commons.SPAN_RESPONSE_UPSTREAM_ID
 import io.emeraldpay.dshackle.commons.SPAN_STATUS_MESSAGE
 import io.emeraldpay.dshackle.config.MainConfig
 import io.emeraldpay.dshackle.quorum.CallQuorum
@@ -133,6 +134,9 @@ open class NativeCall(
 
     private fun completeSpan(callResult: CallResult, requestCount: Int) {
         val span = tracer.currentSpan()
+        callResult.upstreamId?.let {
+            span?.tag(SPAN_RESPONSE_UPSTREAM_ID, it)
+        }
         if (callResult.isError()) {
             errorSpan(span, callResult.error?.message ?: "Internal error")
         }