forked from nokia/restful
-
Notifications
You must be signed in to change notification settings - Fork 0
/
traceb3.go
74 lines (63 loc) · 1.99 KB
/
traceb3.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
// Copyright 2021 Nokia
// Licensed under the BSD 3-Clause License.
// SPDX-License-Identifier: BSD-3-Clause
package restful
import "net/http"
/* Zipkin (B3) and LightStep trace data.
https://istio.io/latest/docs/tasks/observability/distributed-tracing/overview/
https://www.envoyproxy.io/docs/envoy/latest/configuration/http/http_conn_man/headers.html
*/
const (
headerB3TraceID = "X-B3-TraceId"
headerB3ParentSpanID = "X-B3-ParentSpanId"
headerB3SpanID = "X-B3-SpanId"
headerB3Sampled = "X-B3-Sampled"
headerB3Flags = "X-B3-Flags"
headerEnvoyRequestID = "X-Request-Id"
headerLightStepSpanC = "X-Ot-Span-Context"
)
type traceB3 struct {
traceID, parentSpanID, spanID, sampled, flags, requestID, spanCtx string
}
func newTraceB3(r *http.Request) *traceB3 {
b3 := traceB3{
traceID: r.Header.Get(headerB3TraceID),
parentSpanID: r.Header.Get(headerB3ParentSpanID),
spanID: r.Header.Get(headerB3SpanID),
sampled: r.Header.Get(headerB3Sampled),
flags: r.Header.Get(headerB3Flags),
requestID: r.Header.Get(headerEnvoyRequestID),
spanCtx: r.Header.Get(headerLightStepSpanC),
}
if b3.traceID == "" {
return nil
}
return &b3
}
func newTraceB3WithID(traceID string) *traceB3 {
return &traceB3{traceID: traceID}
}
func (b3 *traceB3) span(spanID string) *traceB3 {
newB3 := *b3
newB3.parentSpanID = newB3.spanID
newB3.spanID = spanID
return &newB3
}
func (b3 *traceB3) addHeader(headers http.Header) {
if b3.traceID == "" {
return
}
addHeaderStr(headers, headerB3TraceID, b3.traceID)
addHeaderStr(headers, headerB3ParentSpanID, b3.parentSpanID)
addHeaderStr(headers, headerB3SpanID, b3.spanID)
addHeaderStr(headers, headerB3Sampled, b3.sampled)
addHeaderStr(headers, headerB3Flags, b3.flags)
addHeaderStr(headers, headerEnvoyRequestID, b3.requestID)
addHeaderStr(headers, headerLightStepSpanC, b3.spanCtx)
}
func (b3 *traceB3) string() string {
if b3.traceID != "" {
return b3.traceID + "-" + b3.spanID
}
return b3.spanID
}