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
|
package tracing
import (
"net/http"
opentracing "github.com/opentracing/opentracing-go"
"github.com/opentracing/opentracing-go/ext"
"gitlab.com/gitlab-org/labkit/correlation"
)
// Handler will extract tracing from inbound request.
func Handler(h http.Handler, opts ...HandlerOption) http.Handler {
config := applyHandlerOptions(opts)
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
if isHealthCheck(r) {
h.ServeHTTP(w, r)
return
}
tracer := opentracing.GlobalTracer()
if tracer == nil {
h.ServeHTTP(w, r)
return
}
wireContext, _ := tracer.Extract(
opentracing.HTTPHeaders,
opentracing.HTTPHeadersCarrier(r.Header))
// Create the span referring to the RPC client if available.
// If wireContext == nil, a root span will be created.
additionalStartSpanOpts := []opentracing.StartSpanOption{
ext.RPCServerOption(wireContext),
}
correlationID := correlation.ExtractFromContext(r.Context())
if correlationID != "" {
additionalStartSpanOpts = append(additionalStartSpanOpts, opentracing.Tag{Key: "correlation_id", Value: correlationID})
}
serverSpan := opentracing.StartSpan(
config.getOperationName(r),
additionalStartSpanOpts...,
)
serverSpan.SetTag("http.method", r.Method)
serverSpan.SetTag("http.url", r.URL)
defer serverSpan.Finish()
ctx := opentracing.ContextWithSpan(r.Context(), serverSpan)
h.ServeHTTP(w, r.WithContext(ctx))
})
}
func isHealthCheck(r *http.Request) bool {
return r.URL.Path == "/-/liveness" || r.URL.Path == "/-/readiness"
}
|
