Merge pull request #36 from InVisionApp/send-metrics-to-client-statter

Adding custom statter option for clients to optionally use

middleware_static_filesystem_test.go

@@ -31,7 +31,7 @@ var _ = Describe("Static File Middleware", func() {
 			It("should return a response", func() {
 				path = "/static-examples/dist/"
 
-				request, _ := http.NewRequest("GET", "/dist/test.html", nil)
+				request, _ = http.NewRequest("GET", "/dist/test.html", nil)
 
 				resp := NewStaticFilesystem(testPath+path, "/dist/")(response, request)
 				Expect(resp).To(BeNil())

rye.go

@@ -12,6 +12,7 @@ import (
 	"time"
 
 	//log "github.com/sirupsen/logrus"
+
 	"github.com/cactus/go-statsd-client/statsd"
 )
 
@@ -24,6 +25,12 @@ type MWHandler struct {
 	beforeHandlers []Handler
 }
 
+// CustomStatter allows the client to log any additional statsD metrics Rye
+// computes around the request handler.
+type CustomStatter interface {
+	ReportStats(handlerName string, elapsedTime time.Duration, req *http.Request, resp *Response) error
+}
+
 // Config struct allows you to set a reference to a statsd.Statter and include it's stats rate.
 type Config struct {
 	Statter  statsd.Statter
@@ -33,6 +40,9 @@ type Config struct {
 	NoErrStats        bool
 	NoDurationStats   bool
 	NoStatusCodeStats bool
+
+	// Customer Statter for the client
+	CustomStatter CustomStatter
 }
 
 // JSONStatus is a simple container used for conveying status messages.
@@ -148,6 +158,12 @@ func (m *MWHandler) do(w http.ResponseWriter, r *http.Request, handler Handler)
 			// Record status code metric (default 2xx)
 			go m.reportStatusCode(handlerName, statusCode)
 		}
+
+		// If a CustomStatter is set, send the handler metrics to it.
+		// This allows the client to handle these metrics however it wants.
+		if m.Config.CustomStatter != nil && resp != nil {
+			go m.Config.CustomStatter.ReportStats(handlerName, time.Since(startTime), r, resp)
+		}
 	}()
 
 	// stop executing rest of the

rye_test.go

@@ -36,16 +36,33 @@ type statsTiming struct {
 	StatRate float32
 }
 
+var reportedStats = make(chan fakeReportedStats)
+
+type fakeReportedStats struct {
+	HandlerName string
+	Duration    time.Duration
+	Request     *http.Request
+	Response    *Response
+}
+
+type fakeCustomStatter struct{}
+
+func (fcs *fakeCustomStatter) ReportStats(handler string, dur time.Duration, req *http.Request, res *Response) error {
+	reportedStats <- fakeReportedStats{handler, dur, req, res}
+	return nil
+}
+
 var _ = Describe("Rye", func() {
 
 	var (
-		request     *http.Request
-		response    *httptest.ResponseRecorder
-		mwHandler   *MWHandler
-		ryeConfig   Config
-		fakeStatter *statsdfakes.FakeStatter
-		inc         chan statsInc
-		timing      chan statsTiming
+		request           *http.Request
+		response          *httptest.ResponseRecorder
+		mwHandler         *MWHandler
+		ryeConfig         Config
+		fakeStatter       *statsdfakes.FakeStatter
+		fakeClientStatter *fakeCustomStatter
+		inc               chan statsInc
+		timing            chan statsTiming
 	)
 
 	const (
@@ -54,6 +71,7 @@ var _ = Describe("Rye", func() {
 
 	BeforeEach(func() {
 		fakeStatter = &statsdfakes.FakeStatter{}
+		fakeClientStatter = &fakeCustomStatter{}
 		ryeConfig = Config{
 			Statter:  fakeStatter,
 			StatRate: STATRATE,
@@ -81,7 +99,6 @@ var _ = Describe("Rye", func() {
 			timing <- statsTiming{name, time, statrate}
 			return nil
 		}
-
 	})
 
 	AfterEach(func() {
@@ -329,6 +346,64 @@ var _ = Describe("Rye", func() {
 				Expect(fakeStatter.IncCallCount()).To(Equal(2))
 			})
 		})
+
+		Context("when a custom statter is supplied", func() {
+			It("should call the ReportStats method", func() {
+				ryeConfig := Config{
+					Statter:       fakeStatter,
+					StatRate:      STATRATE,
+					CustomStatter: fakeClientStatter,
+				}
+
+				handler := NewMWHandler(ryeConfig)
+				h := handler.Handle([]Handler{successWithResponse})
+				h.ServeHTTP(response, request)
+
+				Expect(h).ToNot(BeNil())
+				Expect(h).To(BeAssignableToTypeOf(func(http.ResponseWriter, *http.Request) {}))
+
+				Eventually(inc).Should(Receive(Equal(statsInc{"handlers.successWithResponse.200", 1, float32(STATRATE)})))
+				Eventually(timing).Should(Receive(HaveTiming("handlers.successWithResponse.runtime", float32(STATRATE))))
+
+				var receivedReportedStats fakeReportedStats
+				var resp *Response
+
+				Eventually(reportedStats).Should(Receive(&receivedReportedStats))
+				Expect(receivedReportedStats.HandlerName).To(Equal("successWithResponse"))
+				Expect(receivedReportedStats.Duration.Seconds()/1000 > 0).To(Equal(true))
+				Expect(receivedReportedStats.Request).To(BeAssignableToTypeOf(request))
+				Expect(receivedReportedStats.Response).To(BeAssignableToTypeOf(resp))
+				Expect(receivedReportedStats.Response.StatusCode).To(Equal(200))
+			})
+		})
+
+		Context("when a custom statter is NOT supplied", func() {
+			It("should not call the ReportStats method", func() {
+				ryeConfig := Config{
+					Statter:  fakeStatter,
+					StatRate: STATRATE,
+				}
+
+				handler := NewMWHandler(ryeConfig)
+				h := handler.Handle([]Handler{successWithResponse})
+				h.ServeHTTP(response, request)
+
+				Expect(h).ToNot(BeNil())
+				Expect(h).To(BeAssignableToTypeOf(func(http.ResponseWriter, *http.Request) {}))
+
+				Eventually(inc).Should(Receive(Equal(statsInc{"handlers.successWithResponse.200", 1, float32(STATRATE)})))
+				Eventually(timing).Should(Receive(HaveTiming("handlers.successWithResponse.runtime", float32(STATRATE))))
+
+				time.Sleep(time.Millisecond * 10)
+
+				var receivedReportedStats fakeReportedStats
+
+				Expect(receivedReportedStats.HandlerName).To(Equal(""))
+				Expect(receivedReportedStats.Duration.Nanoseconds()).To(Equal(int64(0)))
+				Expect(receivedReportedStats.Request).To(BeNil())
+				Expect(receivedReportedStats.Response).To(BeNil())
+			})
+		})
 	})
 
 	Describe("getFuncName", func() {
@@ -385,6 +460,15 @@ func success2Handler(rw http.ResponseWriter, r *http.Request) *Response {
 	return nil
 }
 
+func successWithResponse(rw http.ResponseWriter, r *http.Request) *Response {
+	return &Response{
+		StatusCode:    200,
+		Err:           nil,
+		StopExecution: false,
+		Context:       context.Background(),
+	}
+}
+
 func badResponseHandler(rw http.ResponseWriter, r *http.Request) *Response {
 	return &Response{}
 }