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Diffstat (limited to 'vendor/go.opencensus.io/exporter/stackdriver/propagation/http.go')
-rw-r--r--vendor/go.opencensus.io/exporter/stackdriver/propagation/http.go94
1 files changed, 0 insertions, 94 deletions
diff --git a/vendor/go.opencensus.io/exporter/stackdriver/propagation/http.go b/vendor/go.opencensus.io/exporter/stackdriver/propagation/http.go
deleted file mode 100644
index 7cc02a1..0000000
--- a/vendor/go.opencensus.io/exporter/stackdriver/propagation/http.go
+++ /dev/null
@@ -1,94 +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 propagation implement X-Cloud-Trace-Context header propagation used
-// by Google Cloud products.
-package propagation // import "go.opencensus.io/exporter/stackdriver/propagation"
-
-import (
- "encoding/binary"
- "encoding/hex"
- "fmt"
- "net/http"
- "strconv"
- "strings"
-
- "go.opencensus.io/trace"
- "go.opencensus.io/trace/propagation"
-)
-
-const (
- httpHeaderMaxSize = 200
- httpHeader = `X-Cloud-Trace-Context`
-)
-
-var _ propagation.HTTPFormat = (*HTTPFormat)(nil)
-
-// HTTPFormat implements propagation.HTTPFormat to propagate
-// traces in HTTP headers for Google Cloud Platform and Stackdriver Trace.
-type HTTPFormat struct{}
-
-// SpanContextFromRequest extracts a Stackdriver Trace span context from incoming requests.
-func (f *HTTPFormat) SpanContextFromRequest(req *http.Request) (sc trace.SpanContext, ok bool) {
- h := req.Header.Get(httpHeader)
- // See https://cloud.google.com/trace/docs/faq for the header HTTPFormat.
- // Return if the header is empty or missing, or if the header is unreasonably
- // large, to avoid making unnecessary copies of a large string.
- if h == "" || len(h) > httpHeaderMaxSize {
- return trace.SpanContext{}, false
- }
-
- // Parse the trace id field.
- slash := strings.Index(h, `/`)
- if slash == -1 {
- return trace.SpanContext{}, false
- }
- tid, h := h[:slash], h[slash+1:]
-
- buf, err := hex.DecodeString(tid)
- if err != nil {
- return trace.SpanContext{}, false
- }
- copy(sc.TraceID[:], buf)
-
- // Parse the span id field.
- spanstr := h
- semicolon := strings.Index(h, `;`)
- if semicolon != -1 {
- spanstr, h = h[:semicolon], h[semicolon+1:]
- }
- sid, err := strconv.ParseUint(spanstr, 10, 64)
- if err != nil {
- return trace.SpanContext{}, false
- }
- binary.BigEndian.PutUint64(sc.SpanID[:], sid)
-
- // Parse the options field, options field is optional.
- if !strings.HasPrefix(h, "o=") {
- return sc, true
- }
- o, err := strconv.ParseUint(h[2:], 10, 64)
- if err != nil {
- return trace.SpanContext{}, false
- }
- sc.TraceOptions = trace.TraceOptions(o)
- return sc, true
-}
-
-// SpanContextToRequest modifies the given request to include a Stackdriver Trace header.
-func (f *HTTPFormat) SpanContextToRequest(sc trace.SpanContext, req *http.Request) {
- sid := binary.BigEndian.Uint64(sc.SpanID[:])
- header := fmt.Sprintf("%s/%d;o=%d", hex.EncodeToString(sc.TraceID[:]), sid, int64(sc.TraceOptions))
- req.Header.Set(httpHeader, header)
-}