W3C TraceContext-like structure for correlating events.
https://www.w3.org/TR/trace-context/
Unique ID for an entire trace tree.
Unique ID for a single span or event within a trace.
Optional
The spanId of the parent span, if any.
spanId
W3C TraceContext-like structure for correlating events.
See
https://www.w3.org/TR/trace-context/