diff options
Diffstat (limited to 'vendor/go.opencensus.io/plugin/ochttp/server.go')
| -rw-r--r-- | vendor/go.opencensus.io/plugin/ochttp/server.go | 424 |
1 files changed, 0 insertions, 424 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 72aa8c2..0000000 --- a/vendor/go.opencensus.io/plugin/ochttp/server.go +++ /dev/null @@ -1,424 +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 - - // 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 -} - -func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) { - var traceEnd, statsEnd func() - r, traceEnd = h.startTrace(w, r) - defer traceEnd() - w, statsEnd = h.startStats(w, r) - defer statsEnd() - handler := h.Handler - if handler == nil { - handler = http.DefaultServeMux - } - handler.ServeHTTP(w, r) -} - -func (h *Handler) startTrace(w http.ResponseWriter, r *http.Request) (*http.Request, func()) { - if 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() - var span *trace.Span - sc, ok := h.extractSpanContext(r) - if ok && !h.IsPublicEndpoint { - ctx, span = trace.StartSpanWithRemoteParent(ctx, name, sc, - trace.WithSampler(h.StartOptions.Sampler), - trace.WithSpanKind(trace.SpanKindServer)) - } else { - ctx, span = trace.StartSpan(ctx, name, - trace.WithSampler(h.StartOptions.Sampler), - trace.WithSpanKind(trace.SpanKindServer), - ) - if ok { - span.AddLink(trace.Link{ - TraceID: sc.TraceID, - SpanID: sc.SpanID, - Type: trace.LinkTypeChild, - Attributes: nil, - }) - } - } - span.AddAttributes(requestAttrs(r)...) - 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()) { - ctx, _ := tag.New(r.Context(), - tag.Upsert(Host, r.URL.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() { - t.endOnce.Do(func() { - if t.statusCode == 0 { - t.statusCode = 200 - } - - span := trace.FromContext(t.ctx) - span.SetStatus(TraceStatus(t.statusCode, t.statusLine)) - - 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)) - } - ctx, _ := tag.New(t.ctx, tag.Upsert(StatusCode, strconv.Itoa(t.statusCode))) - stats.Record(ctx, 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) - 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} - } -} |