tracedata

type TraceData interface {
	// Span spans the existing trace data and puts that into the request.
	// Returns the updated request, a trace string for logging and a span end function or nil.
	// Does not change the input trace data.
	Span(r *http.Request) (*http.Request, string, func())

	// SetHeader sets request headers according to the trace data.
	// Input headers object must not be nil.
	SetHeader(header http.Header)

	// IsReceived tells whether trace data was received (parsed from a request) or a random one.
	IsReceived() bool

	// String makes a log string from trace data.
	String() string

	// TraceID returns the trace ID of the trace data.
	TraceID() string

	// SpanID returns the span ID of the trace data.
	SpanID() string
}