package tracing import ( "fmt" "io" "net/http" "github.com/containous/traefik/log" "github.com/containous/traefik/middlewares/tracing/datadog" "github.com/containous/traefik/middlewares/tracing/jaeger" "github.com/containous/traefik/middlewares/tracing/zipkin" "github.com/opentracing/opentracing-go" "github.com/opentracing/opentracing-go/ext" ) // Tracing middleware type Tracing struct { Backend string `description:"Selects the tracking backend ('jaeger','zipkin', 'datadog')." export:"true"` ServiceName string `description:"Set the name for this service" export:"true"` Jaeger *jaeger.Config `description:"Settings for jaeger"` Zipkin *zipkin.Config `description:"Settings for zipkin"` DataDog *datadog.Config `description:"Settings for DataDog"` tracer opentracing.Tracer closer io.Closer } // StartSpan delegates to opentracing.Tracer func (t *Tracing) StartSpan(operationName string, opts ...opentracing.StartSpanOption) opentracing.Span { return t.tracer.StartSpan(operationName, opts...) } // Inject delegates to opentracing.Tracer func (t *Tracing) Inject(sm opentracing.SpanContext, format interface{}, carrier interface{}) error { return t.tracer.Inject(sm, format, carrier) } // Extract delegates to opentracing.Tracer func (t *Tracing) Extract(format interface{}, carrier interface{}) (opentracing.SpanContext, error) { return t.tracer.Extract(format, carrier) } // Backend describes things we can use to setup tracing type Backend interface { Setup(serviceName string) (opentracing.Tracer, io.Closer, error) } // Setup Tracing middleware func (t *Tracing) Setup() { var err error switch t.Backend { case jaeger.Name: t.tracer, t.closer, err = t.Jaeger.Setup(t.ServiceName) case zipkin.Name: t.tracer, t.closer, err = t.Zipkin.Setup(t.ServiceName) case datadog.Name: t.tracer, t.closer, err = t.DataDog.Setup(t.ServiceName) default: log.Warnf("Unknown tracer %q", t.Backend) return } if err != nil { log.Warnf("Could not initialize %s tracing: %v", t.Backend, err) } } // IsEnabled determines if tracing was successfully activated func (t *Tracing) IsEnabled() bool { if t == nil || t.tracer == nil { return false } return true } // Close tracer func (t *Tracing) Close() { if t.closer != nil { err := t.closer.Close() if err != nil { log.Warn(err) } } } // LogRequest used to create span tags from the request func LogRequest(span opentracing.Span, r *http.Request) { if span != nil && r != nil { ext.HTTPMethod.Set(span, r.Method) ext.HTTPUrl.Set(span, r.URL.String()) span.SetTag("http.host", r.Host) } } // LogResponseCode used to log response code in span func LogResponseCode(span opentracing.Span, code int) { if span != nil { ext.HTTPStatusCode.Set(span, uint16(code)) if code >= 400 { ext.Error.Set(span, true) } } } // GetSpan used to retrieve span from request context func GetSpan(r *http.Request) opentracing.Span { return opentracing.SpanFromContext(r.Context()) } // InjectRequestHeaders used to inject OpenTracing headers into the request func InjectRequestHeaders(r *http.Request) { if span := GetSpan(r); span != nil { err := opentracing.GlobalTracer().Inject( span.Context(), opentracing.HTTPHeaders, opentracing.HTTPHeadersCarrier(r.Header)) if err != nil { log.Error(err) } } } // LogEventf logs an event to the span in the request context. func LogEventf(r *http.Request, format string, args ...interface{}) { if span := GetSpan(r); span != nil { span.LogKV("event", fmt.Sprintf(format, args...)) } } // StartSpan starts a new span from the one in the request context func StartSpan(r *http.Request, operationName string, spanKinClient bool, opts ...opentracing.StartSpanOption) (opentracing.Span, *http.Request, func()) { span, ctx := opentracing.StartSpanFromContext(r.Context(), operationName, opts...) if spanKinClient { ext.SpanKindRPCClient.Set(span) } r = r.WithContext(ctx) return span, r, func() { span.Finish() } } // SetError flags the span associated with this request as in error func SetError(r *http.Request) { if span := GetSpan(r); span != nil { ext.Error.Set(span, true) } } // SetErrorAndDebugLog flags the span associated with this request as in error and create a debug log func SetErrorAndDebugLog(r *http.Request, format string, args ...interface{}) { SetError(r) log.Debugf(format, args...) LogEventf(r, format, args...) } // SetErrorAndWarnLog flags the span associated with this request as in error and create a debug log func SetErrorAndWarnLog(r *http.Request, format string, args ...interface{}) { SetError(r) log.Warnf(format, args...) LogEventf(r, format, args...) }