/*
Wraps the RoundTrip function of the given RoundTripper.
Will provide accounting metrics for the http.Request / http.Response life-cycle
Callers of RoundTrip are responsible for setting the ‘X-CF-RequestID’ field in the request header if they have one.
Callers are also responsible for setting the ‘X-CF-ApplicationID’ and ‘X-CF-InstanceIndex’ fields in the request header if they are known.
*/
func (irt *instrumentedRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
requestId, err := GenerateUuid()
if err != nil {
log.Printf("failed to generated request ID: %v\n", err)
requestId = &uuid.UUID{}
}
startTime := time.Now()
parentRequestId := req.Header.Get("X-CF-RequestID")
req.Header.Set("X-CF-RequestID", requestId.String())
resp, roundTripErr := irt.roundTripper.RoundTrip(req)
var statusCode int
var contentLength int64
if roundTripErr == nil {
statusCode = resp.StatusCode
contentLength = resp.ContentLength
}
httpStartStop := factories.NewHttpStartStop(req, statusCode, contentLength, events.PeerType_Client, requestId)
if parentRequestId != "" {
if id, err := uuid.ParseHex(parentRequestId); err == nil {
httpStartStop.ParentRequestId = factories.NewUUID(id)
}
}
httpStartStop.StartTimestamp = proto.Int64(startTime.UnixNano())
err = irt.emitter.Emit(httpStartStop)
if err != nil {
log.Printf("failed to emit startstop event: %v\n", err)
}
return resp, roundTripErr
}
/*
Wraps the given http.Handler ServerHTTP function
Will provide accounting metrics for the http.Request / http.Response life-cycle
*/
func (ih *instrumentedHandler) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
requestId, err := uuid.ParseHex(req.Header.Get("X-Vcap-Request-Id"))
if err != nil {
requestId, err = GenerateUuid()
if err != nil {
log.Printf("failed to generated request ID: %v\n", err)
requestId = &uuid.UUID{}
}
req.Header.Set("X-Vcap-Request-Id", requestId.String())
}
rw.Header().Set("X-Vcap-Request-Id", requestId.String())
startTime := time.Now()
instrumentedWriter := &instrumentedResponseWriter{writer: rw, statusCode: 200}
ih.handler.ServeHTTP(instrumentedWriter, req)
startStopEvent := factories.NewHttpStartStop(req, instrumentedWriter.statusCode, instrumentedWriter.contentLength, events.PeerType_Server, requestId)
startStopEvent.StartTimestamp = proto.Int64(startTime.UnixNano())
err = ih.emitter.Emit(startStopEvent)
if err != nil {
log.Printf("failed to emit startstop event: %v\n", err)
}
}
func createEnvelope(eventType events.Envelope_EventType) *events.Envelope {
envelope := &events.Envelope{Origin: proto.String("origin"), EventType: &eventType, Timestamp: proto.Int64(time.Now().UnixNano())}
switch eventType {
case events.Envelope_HttpStartStop:
req, _ := http.NewRequest("GET", "http://www.example.com", nil)
req.RemoteAddr = "www.example.com"
req.Header.Add("User-Agent", "user-agent")
uuid, _ := uuid.NewV4()
envelope.HttpStartStop = factories.NewHttpStartStop(req, http.StatusOK, 128, events.PeerType_Client, uuid)
case events.Envelope_ValueMetric:
envelope.ValueMetric = factories.NewValueMetric("some-value-metric", 123, "km")
case events.Envelope_CounterEvent:
envelope.CounterEvent = factories.NewCounterEvent("some-counter-event", 123)
case events.Envelope_LogMessage:
envelope.LogMessage = factories.NewLogMessage(events.LogMessage_OUT, "some message", "appId", "source")
case events.Envelope_ContainerMetric:
envelope.ContainerMetric = factories.NewContainerMetric("appID", 123, 1, 5, 5)
case events.Envelope_Error:
envelope.Error = factories.NewError("source", 123, "message")
default:
panic(fmt.Sprintf("Unknown event %v\n", eventType))
}
return envelope
}
/*
RoundTrip wraps the RoundTrip function of the given RoundTripper.
Will provide accounting metrics for the http.Request / http.Response life-cycle
Callers of RoundTrip are responsible for setting the ‘X-Vcap-Request-Id’ field in the request header if they have one.
Callers are also responsible for setting the ‘X-CF-ApplicationID’ and ‘X-CF-InstanceIndex’ fields in the request header if they are known.
*/
func (irt *instrumentedRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
startTime := time.Now()
requestId := req.Header.Get("X-Vcap-Request-Id")
if requestId == "" {
requestIdGuid, err := uuid.NewV4()
if err != nil {
return nil, err
}
requestId = requestIdGuid.String()
}
req.Header.Set("X-Vcap-Request-Id", requestId)
resp, roundTripErr := irt.roundTripper.RoundTrip(req)
var statusCode int
var contentLength int64
if roundTripErr == nil {
statusCode = resp.StatusCode
contentLength = resp.ContentLength
}
id, err := uuid.ParseHex(requestId)
if err != nil {
return nil, err
}
httpStartStop := factories.NewHttpStartStop(req, statusCode, contentLength, events.PeerType_Client, id)
httpStartStop.StartTimestamp = proto.Int64(startTime.UnixNano())
err = irt.emitter.Emit(httpStartStop)
if err != nil {
log.Printf("failed to emit startstop event: %v\n", err)
}
return resp, roundTripErr
}