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path: root/vendor/go.opencensus.io/plugin/ochttp/server.go
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Diffstat (limited to 'vendor/go.opencensus.io/plugin/ochttp/server.go')
-rw-r--r--vendor/go.opencensus.io/plugin/ochttp/server.go455
1 files changed, 0 insertions, 455 deletions
diff --git a/vendor/go.opencensus.io/plugin/ochttp/server.go b/vendor/go.opencensus.io/plugin/ochttp/server.go
deleted file mode 100644
index f7c8434..0000000
--- a/vendor/go.opencensus.io/plugin/ochttp/server.go
+++ /dev/null
@@ -1,455 +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 ochttp
-
-import (
- "context"
- "io"
- "net/http"
- "strconv"
- "sync"
- "time"
-
- "go.opencensus.io/stats"
- "go.opencensus.io/tag"
- "go.opencensus.io/trace"
- "go.opencensus.io/trace/propagation"
-)
-
-// Handler is an http.Handler wrapper to instrument your HTTP server with
-// OpenCensus. It supports both stats and tracing.
-//
-// # Tracing
-//
-// This handler is aware of the incoming request's span, reading it from request
-// headers as configured using the Propagation field.
-// The extracted span can be accessed from the incoming request's
-// context.
-//
-// span := trace.FromContext(r.Context())
-//
-// The server span will be automatically ended at the end of ServeHTTP.
-type Handler struct {
- // Propagation defines how traces are propagated. If unspecified,
- // B3 propagation will be used.
- Propagation propagation.HTTPFormat
-
- // Handler is the handler used to handle the incoming request.
- Handler http.Handler
-
- // StartOptions are applied to the span started by this Handler around each
- // request.
- //
- // StartOptions.SpanKind will always be set to trace.SpanKindServer
- // for spans started by this transport.
- StartOptions trace.StartOptions
-
- // GetStartOptions allows to set start options per request. If set,
- // StartOptions is going to be ignored.
- GetStartOptions func(*http.Request) trace.StartOptions
-
- // IsPublicEndpoint should be set to true for publicly accessible HTTP(S)
- // servers. If true, any trace metadata set on the incoming request will
- // be added as a linked trace instead of being added as a parent of the
- // current trace.
- IsPublicEndpoint bool
-
- // FormatSpanName holds the function to use for generating the span name
- // from the information found in the incoming HTTP Request. By default the
- // name equals the URL Path.
- FormatSpanName func(*http.Request) string
-
- // IsHealthEndpoint holds the function to use for determining if the
- // incoming HTTP request should be considered a health check. This is in
- // addition to the private isHealthEndpoint func which may also indicate
- // tracing should be skipped.
- IsHealthEndpoint func(*http.Request) bool
-}
-
-func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
- var tags addedTags
- r, traceEnd := h.startTrace(w, r)
- defer traceEnd()
- w, statsEnd := h.startStats(w, r)
- defer statsEnd(&tags)
- handler := h.Handler
- if handler == nil {
- handler = http.DefaultServeMux
- }
- r = r.WithContext(context.WithValue(r.Context(), addedTagsKey{}, &tags))
- handler.ServeHTTP(w, r)
-}
-
-func (h *Handler) startTrace(w http.ResponseWriter, r *http.Request) (*http.Request, func()) {
- if h.IsHealthEndpoint != nil && h.IsHealthEndpoint(r) || isHealthEndpoint(r.URL.Path) {
- return r, func() {}
- }
- var name string
- if h.FormatSpanName == nil {
- name = spanNameFromURL(r)
- } else {
- name = h.FormatSpanName(r)
- }
- ctx := r.Context()
-
- startOpts := h.StartOptions
- if h.GetStartOptions != nil {
- startOpts = h.GetStartOptions(r)
- }
-
- var span *trace.Span
- sc, ok := h.extractSpanContext(r)
- if ok && !h.IsPublicEndpoint {
- ctx, span = trace.StartSpanWithRemoteParent(ctx, name, sc,
- trace.WithSampler(startOpts.Sampler),
- trace.WithSpanKind(trace.SpanKindServer))
- } else {
- ctx, span = trace.StartSpan(ctx, name,
- trace.WithSampler(startOpts.Sampler),
- trace.WithSpanKind(trace.SpanKindServer),
- )
- if ok {
- span.AddLink(trace.Link{
- TraceID: sc.TraceID,
- SpanID: sc.SpanID,
- Type: trace.LinkTypeParent,
- Attributes: nil,
- })
- }
- }
- span.AddAttributes(requestAttrs(r)...)
- if r.Body == nil {
- // TODO: Handle cases where ContentLength is not set.
- } else if r.ContentLength > 0 {
- span.AddMessageReceiveEvent(0, /* TODO: messageID */
- r.ContentLength, -1)
- }
- return r.WithContext(ctx), span.End
-}
-
-func (h *Handler) extractSpanContext(r *http.Request) (trace.SpanContext, bool) {
- if h.Propagation == nil {
- return defaultFormat.SpanContextFromRequest(r)
- }
- return h.Propagation.SpanContextFromRequest(r)
-}
-
-func (h *Handler) startStats(w http.ResponseWriter, r *http.Request) (http.ResponseWriter, func(tags *addedTags)) {
- ctx, _ := tag.New(r.Context(),
- tag.Upsert(Host, r.Host),
- tag.Upsert(Path, r.URL.Path),
- tag.Upsert(Method, r.Method))
- track := &trackingResponseWriter{
- start: time.Now(),
- ctx: ctx,
- writer: w,
- }
- if r.Body == nil {
- // TODO: Handle cases where ContentLength is not set.
- track.reqSize = -1
- } else if r.ContentLength > 0 {
- track.reqSize = r.ContentLength
- }
- stats.Record(ctx, ServerRequestCount.M(1))
- return track.wrappedResponseWriter(), track.end
-}
-
-type trackingResponseWriter struct {
- ctx context.Context
- reqSize int64
- respSize int64
- start time.Time
- statusCode int
- statusLine string
- endOnce sync.Once
- writer http.ResponseWriter
-}
-
-// Compile time assertion for ResponseWriter interface
-var _ http.ResponseWriter = (*trackingResponseWriter)(nil)
-
-func (t *trackingResponseWriter) end(tags *addedTags) {
- t.endOnce.Do(func() {
- if t.statusCode == 0 {
- t.statusCode = 200
- }
-
- span := trace.FromContext(t.ctx)
- span.SetStatus(TraceStatus(t.statusCode, t.statusLine))
- span.AddAttributes(trace.Int64Attribute(StatusCodeAttribute, int64(t.statusCode)))
-
- m := []stats.Measurement{
- ServerLatency.M(float64(time.Since(t.start)) / float64(time.Millisecond)),
- ServerResponseBytes.M(t.respSize),
- }
- if t.reqSize >= 0 {
- m = append(m, ServerRequestBytes.M(t.reqSize))
- }
- allTags := make([]tag.Mutator, len(tags.t)+1)
- allTags[0] = tag.Upsert(StatusCode, strconv.Itoa(t.statusCode))
- copy(allTags[1:], tags.t)
- stats.RecordWithTags(t.ctx, allTags, m...)
- })
-}
-
-func (t *trackingResponseWriter) Header() http.Header {
- return t.writer.Header()
-}
-
-func (t *trackingResponseWriter) Write(data []byte) (int, error) {
- n, err := t.writer.Write(data)
- t.respSize += int64(n)
- // Add message event for request bytes sent.
- span := trace.FromContext(t.ctx)
- span.AddMessageSendEvent(0 /* TODO: messageID */, int64(n), -1)
- return n, err
-}
-
-func (t *trackingResponseWriter) WriteHeader(statusCode int) {
- t.writer.WriteHeader(statusCode)
- t.statusCode = statusCode
- t.statusLine = http.StatusText(t.statusCode)
-}
-
-// wrappedResponseWriter returns a wrapped version of the original
-//
-// ResponseWriter and only implements the same combination of additional
-//
-// interfaces as the original.
-// This implementation is based on https://github.com/felixge/httpsnoop.
-func (t *trackingResponseWriter) wrappedResponseWriter() http.ResponseWriter {
- var (
- hj, i0 = t.writer.(http.Hijacker)
- cn, i1 = t.writer.(http.CloseNotifier)
- pu, i2 = t.writer.(http.Pusher)
- fl, i3 = t.writer.(http.Flusher)
- rf, i4 = t.writer.(io.ReaderFrom)
- )
-
- switch {
- case !i0 && !i1 && !i2 && !i3 && !i4:
- return struct {
- http.ResponseWriter
- }{t}
- case !i0 && !i1 && !i2 && !i3 && i4:
- return struct {
- http.ResponseWriter
- io.ReaderFrom
- }{t, rf}
- case !i0 && !i1 && !i2 && i3 && !i4:
- return struct {
- http.ResponseWriter
- http.Flusher
- }{t, fl}
- case !i0 && !i1 && !i2 && i3 && i4:
- return struct {
- http.ResponseWriter
- http.Flusher
- io.ReaderFrom
- }{t, fl, rf}
- case !i0 && !i1 && i2 && !i3 && !i4:
- return struct {
- http.ResponseWriter
- http.Pusher
- }{t, pu}
- case !i0 && !i1 && i2 && !i3 && i4:
- return struct {
- http.ResponseWriter
- http.Pusher
- io.ReaderFrom
- }{t, pu, rf}
- case !i0 && !i1 && i2 && i3 && !i4:
- return struct {
- http.ResponseWriter
- http.Pusher
- http.Flusher
- }{t, pu, fl}
- case !i0 && !i1 && i2 && i3 && i4:
- return struct {
- http.ResponseWriter
- http.Pusher
- http.Flusher
- io.ReaderFrom
- }{t, pu, fl, rf}
- case !i0 && i1 && !i2 && !i3 && !i4:
- return struct {
- http.ResponseWriter
- http.CloseNotifier
- }{t, cn}
- case !i0 && i1 && !i2 && !i3 && i4:
- return struct {
- http.ResponseWriter
- http.CloseNotifier
- io.ReaderFrom
- }{t, cn, rf}
- case !i0 && i1 && !i2 && i3 && !i4:
- return struct {
- http.ResponseWriter
- http.CloseNotifier
- http.Flusher
- }{t, cn, fl}
- case !i0 && i1 && !i2 && i3 && i4:
- return struct {
- http.ResponseWriter
- http.CloseNotifier
- http.Flusher
- io.ReaderFrom
- }{t, cn, fl, rf}
- case !i0 && i1 && i2 && !i3 && !i4:
- return struct {
- http.ResponseWriter
- http.CloseNotifier
- http.Pusher
- }{t, cn, pu}
- case !i0 && i1 && i2 && !i3 && i4:
- return struct {
- http.ResponseWriter
- http.CloseNotifier
- http.Pusher
- io.ReaderFrom
- }{t, cn, pu, rf}
- case !i0 && i1 && i2 && i3 && !i4:
- return struct {
- http.ResponseWriter
- http.CloseNotifier
- http.Pusher
- http.Flusher
- }{t, cn, pu, fl}
- case !i0 && i1 && i2 && i3 && i4:
- return struct {
- http.ResponseWriter
- http.CloseNotifier
- http.Pusher
- http.Flusher
- io.ReaderFrom
- }{t, cn, pu, fl, rf}
- case i0 && !i1 && !i2 && !i3 && !i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- }{t, hj}
- case i0 && !i1 && !i2 && !i3 && i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- io.ReaderFrom
- }{t, hj, rf}
- case i0 && !i1 && !i2 && i3 && !i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.Flusher
- }{t, hj, fl}
- case i0 && !i1 && !i2 && i3 && i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.Flusher
- io.ReaderFrom
- }{t, hj, fl, rf}
- case i0 && !i1 && i2 && !i3 && !i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.Pusher
- }{t, hj, pu}
- case i0 && !i1 && i2 && !i3 && i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.Pusher
- io.ReaderFrom
- }{t, hj, pu, rf}
- case i0 && !i1 && i2 && i3 && !i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.Pusher
- http.Flusher
- }{t, hj, pu, fl}
- case i0 && !i1 && i2 && i3 && i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.Pusher
- http.Flusher
- io.ReaderFrom
- }{t, hj, pu, fl, rf}
- case i0 && i1 && !i2 && !i3 && !i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.CloseNotifier
- }{t, hj, cn}
- case i0 && i1 && !i2 && !i3 && i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.CloseNotifier
- io.ReaderFrom
- }{t, hj, cn, rf}
- case i0 && i1 && !i2 && i3 && !i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.CloseNotifier
- http.Flusher
- }{t, hj, cn, fl}
- case i0 && i1 && !i2 && i3 && i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.CloseNotifier
- http.Flusher
- io.ReaderFrom
- }{t, hj, cn, fl, rf}
- case i0 && i1 && i2 && !i3 && !i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.CloseNotifier
- http.Pusher
- }{t, hj, cn, pu}
- case i0 && i1 && i2 && !i3 && i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.CloseNotifier
- http.Pusher
- io.ReaderFrom
- }{t, hj, cn, pu, rf}
- case i0 && i1 && i2 && i3 && !i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.CloseNotifier
- http.Pusher
- http.Flusher
- }{t, hj, cn, pu, fl}
- case i0 && i1 && i2 && i3 && i4:
- return struct {
- http.ResponseWriter
- http.Hijacker
- http.CloseNotifier
- http.Pusher
- http.Flusher
- io.ReaderFrom
- }{t, hj, cn, pu, fl, rf}
- default:
- return struct {
- http.ResponseWriter
- }{t}
- }
-}