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Diffstat (limited to 'vendor/go.opencensus.io/plugin/ochttp/propagation/b3/b3.go')
-rw-r--r--vendor/go.opencensus.io/plugin/ochttp/propagation/b3/b3.go123
1 files changed, 0 insertions, 123 deletions
diff --git a/vendor/go.opencensus.io/plugin/ochttp/propagation/b3/b3.go b/vendor/go.opencensus.io/plugin/ochttp/propagation/b3/b3.go
deleted file mode 100644
index f777772..0000000
--- a/vendor/go.opencensus.io/plugin/ochttp/propagation/b3/b3.go
+++ /dev/null
@@ -1,123 +0,0 @@
-// Copyright 2018, OpenCensus Authors
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// Package b3 contains a propagation.HTTPFormat implementation
-// for B3 propagation. See https://github.com/openzipkin/b3-propagation
-// for more details.
-package b3 // import "go.opencensus.io/plugin/ochttp/propagation/b3"
-
-import (
- "encoding/hex"
- "net/http"
-
- "go.opencensus.io/trace"
- "go.opencensus.io/trace/propagation"
-)
-
-// B3 headers that OpenCensus understands.
-const (
- TraceIDHeader = "X-B3-TraceId"
- SpanIDHeader = "X-B3-SpanId"
- SampledHeader = "X-B3-Sampled"
-)
-
-// HTTPFormat implements propagation.HTTPFormat to propagate
-// traces in HTTP headers in B3 propagation format.
-// HTTPFormat skips the X-B3-ParentId and X-B3-Flags headers
-// because there are additional fields not represented in the
-// OpenCensus span context. Spans created from the incoming
-// header will be the direct children of the client-side span.
-// Similarly, reciever of the outgoing spans should use client-side
-// span created by OpenCensus as the parent.
-type HTTPFormat struct{}
-
-var _ propagation.HTTPFormat = (*HTTPFormat)(nil)
-
-// SpanContextFromRequest extracts a B3 span context from incoming requests.
-func (f *HTTPFormat) SpanContextFromRequest(req *http.Request) (sc trace.SpanContext, ok bool) {
- tid, ok := ParseTraceID(req.Header.Get(TraceIDHeader))
- if !ok {
- return trace.SpanContext{}, false
- }
- sid, ok := ParseSpanID(req.Header.Get(SpanIDHeader))
- if !ok {
- return trace.SpanContext{}, false
- }
- sampled, _ := ParseSampled(req.Header.Get(SampledHeader))
- return trace.SpanContext{
- TraceID: tid,
- SpanID: sid,
- TraceOptions: sampled,
- }, true
-}
-
-// ParseTraceID parses the value of the X-B3-TraceId header.
-func ParseTraceID(tid string) (trace.TraceID, bool) {
- if tid == "" {
- return trace.TraceID{}, false
- }
- b, err := hex.DecodeString(tid)
- if err != nil {
- return trace.TraceID{}, false
- }
- var traceID trace.TraceID
- if len(b) <= 8 {
- // The lower 64-bits.
- start := 8 + (8 - len(b))
- copy(traceID[start:], b)
- } else {
- start := 16 - len(b)
- copy(traceID[start:], b)
- }
-
- return traceID, true
-}
-
-// ParseSpanID parses the value of the X-B3-SpanId or X-B3-ParentSpanId headers.
-func ParseSpanID(sid string) (spanID trace.SpanID, ok bool) {
- if sid == "" {
- return trace.SpanID{}, false
- }
- b, err := hex.DecodeString(sid)
- if err != nil {
- return trace.SpanID{}, false
- }
- start := 8 - len(b)
- copy(spanID[start:], b)
- return spanID, true
-}
-
-// ParseSampled parses the value of the X-B3-Sampled header.
-func ParseSampled(sampled string) (trace.TraceOptions, bool) {
- switch sampled {
- case "true", "1":
- return trace.TraceOptions(1), true
- default:
- return trace.TraceOptions(0), false
- }
-}
-
-// SpanContextToRequest modifies the given request to include B3 headers.
-func (f *HTTPFormat) SpanContextToRequest(sc trace.SpanContext, req *http.Request) {
- req.Header.Set(TraceIDHeader, hex.EncodeToString(sc.TraceID[:]))
- req.Header.Set(SpanIDHeader, hex.EncodeToString(sc.SpanID[:]))
-
- var sampled string
- if sc.IsSampled() {
- sampled = "1"
- } else {
- sampled = "0"
- }
- req.Header.Set(SampledHeader, sampled)
-}