57 lines
1.9 KiB
Go
57 lines
1.9 KiB
Go
package tracing
|
|
|
|
import (
|
|
"fmt"
|
|
"net/http"
|
|
|
|
"github.com/containous/traefik/log"
|
|
"github.com/opentracing/opentracing-go"
|
|
"github.com/opentracing/opentracing-go/ext"
|
|
"github.com/urfave/negroni"
|
|
)
|
|
|
|
type entryPointMiddleware struct {
|
|
entryPoint string
|
|
*Tracing
|
|
}
|
|
|
|
// NewEntryPoint creates a new middleware that the incoming request
|
|
func (t *Tracing) NewEntryPoint(name string) negroni.Handler {
|
|
log.Debug("Added entrypoint tracing middleware")
|
|
return &entryPointMiddleware{Tracing: t, entryPoint: name}
|
|
}
|
|
|
|
func (e *entryPointMiddleware) ServeHTTP(w http.ResponseWriter, r *http.Request, next http.HandlerFunc) {
|
|
opNameFunc := generateEntryPointSpanName
|
|
|
|
ctx, _ := e.Extract(opentracing.HTTPHeaders, opentracing.HTTPHeadersCarrier(r.Header))
|
|
span := e.StartSpan(opNameFunc(r, e.entryPoint, e.SpanNameLimit), ext.RPCServerOption(ctx))
|
|
ext.Component.Set(span, e.ServiceName)
|
|
LogRequest(span, r)
|
|
ext.SpanKindRPCServer.Set(span)
|
|
|
|
r = r.WithContext(opentracing.ContextWithSpan(r.Context(), span))
|
|
|
|
recorder := newStatusCodeRecoder(w, 200)
|
|
next(recorder, r)
|
|
|
|
LogResponseCode(span, recorder.Status())
|
|
span.Finish()
|
|
}
|
|
|
|
// generateEntryPointSpanName will return a Span name of an appropriate lenth based on the 'spanLimit' argument. If needed, it will be truncated, but will not be less than 24 characters.
|
|
func generateEntryPointSpanName(r *http.Request, entryPoint string, spanLimit int) string {
|
|
name := fmt.Sprintf("Entrypoint %s %s", entryPoint, r.Host)
|
|
|
|
if spanLimit > 0 && len(name) > spanLimit {
|
|
if spanLimit < EntryPointMaxLengthNumber {
|
|
log.Warnf("SpanNameLimit is set to be less than required static number of characters, defaulting to %d + 3", EntryPointMaxLengthNumber)
|
|
spanLimit = EntryPointMaxLengthNumber + 3
|
|
}
|
|
hash := computeHash(name)
|
|
limit := (spanLimit - EntryPointMaxLengthNumber) / 2
|
|
name = fmt.Sprintf("Entrypoint %s %s %s", truncateString(entryPoint, limit), truncateString(r.Host, limit), hash)
|
|
}
|
|
|
|
return name
|
|
}
|