diff options
Diffstat (limited to 'vendor/go.opencensus.io/plugin/ochttp/server.go')
| -rw-r--r-- | vendor/go.opencensus.io/plugin/ochttp/server.go | 291 |
1 files changed, 249 insertions, 42 deletions
diff --git a/vendor/go.opencensus.io/plugin/ochttp/server.go b/vendor/go.opencensus.io/plugin/ochttp/server.go index 4b3c855..72aa8c2 100644 --- a/vendor/go.opencensus.io/plugin/ochttp/server.go +++ b/vendor/go.opencensus.io/plugin/ochttp/server.go @@ -15,10 +15,8 @@ package ochttp import ( - "bufio" "context" - "errors" - "net" + "io" "net/http" "strconv" "sync" @@ -30,16 +28,19 @@ import ( "go.opencensus.io/trace/propagation" ) -// Handler is a http.Handler that is aware of the incoming request's span. +// 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. -// -// Incoming propagation mechanism is determined by the given HTTP propagators. type Handler struct { // Propagation defines how traces are propagated. If unspecified, // B3 propagation will be used. @@ -60,6 +61,11 @@ type Handler struct { // 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) { @@ -76,7 +82,15 @@ func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) { } func (h *Handler) startTrace(w http.ResponseWriter, r *http.Request) (*http.Request, func()) { - name := spanNameFromURL(r.URL) + 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) @@ -126,7 +140,7 @@ func (h *Handler) startStats(w http.ResponseWriter, r *http.Request) (http.Respo track.reqSize = r.ContentLength } stats.Record(ctx, ServerRequestCount.M(1)) - return track, track.end + return track.wrappedResponseWriter(), track.end } type trackingResponseWriter struct { @@ -140,39 +154,9 @@ type trackingResponseWriter struct { writer http.ResponseWriter } -// Compile time assertions for widely used net/http interfaces -var _ http.CloseNotifier = (*trackingResponseWriter)(nil) -var _ http.Flusher = (*trackingResponseWriter)(nil) -var _ http.Hijacker = (*trackingResponseWriter)(nil) -var _ http.Pusher = (*trackingResponseWriter)(nil) +// Compile time assertion for ResponseWriter interface var _ http.ResponseWriter = (*trackingResponseWriter)(nil) -var errHijackerUnimplemented = errors.New("ResponseWriter does not implement http.Hijacker") - -func (t *trackingResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) { - hj, ok := t.writer.(http.Hijacker) - if !ok { - return nil, nil, errHijackerUnimplemented - } - return hj.Hijack() -} - -func (t *trackingResponseWriter) CloseNotify() <-chan bool { - cn, ok := t.writer.(http.CloseNotifier) - if !ok { - return nil - } - return cn.CloseNotify() -} - -func (t *trackingResponseWriter) Push(target string, opts *http.PushOptions) error { - pusher, ok := t.writer.(http.Pusher) - if !ok { - return http.ErrNotSupported - } - return pusher.Push(target, opts) -} - func (t *trackingResponseWriter) end() { t.endOnce.Do(func() { if t.statusCode == 0 { @@ -210,8 +194,231 @@ func (t *trackingResponseWriter) WriteHeader(statusCode int) { t.statusLine = http.StatusText(t.statusCode) } -func (t *trackingResponseWriter) Flush() { - if flusher, ok := t.writer.(http.Flusher); ok { - flusher.Flush() +// 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} } } |