Add the ability to specify ServerBefore & ServerAfter multiple times in the ServerOption section

transport/grpc/server.go

@@ -59,13 +59,13 @@ type ServerOption func(*Server)
 // ServerBefore functions are executed on the HTTP request object before the
 // request is decoded.
 func ServerBefore(before ...RequestFunc) ServerOption {
-	return func(s *Server) { s.before = before }
+	return func(s *Server) { s.before = append(s.before, before...) }
 }
 
 // ServerAfter functions are executed on the HTTP response writer after the
 // endpoint is invoked, but before anything is written to the client.
 func ServerAfter(after ...ResponseFunc) ServerOption {
-	return func(s *Server) { s.after = after }
+	return func(s *Server) { s.after = append(s.after, after...) }
 }
 
 // ServerErrorLogger is used to log non-terminal errors. By default, no errors

transport/http/server.go

@@ -51,13 +51,13 @@ type ServerOption func(*Server)
 // ServerBefore functions are executed on the HTTP request object before the
 // request is decoded.
 func ServerBefore(before ...RequestFunc) ServerOption {
-	return func(s *Server) { s.before = before }
+	return func(s *Server) { s.before = append(s.before, before...) }
 }
 
 // ServerAfter functions are executed on the HTTP response writer after the
 // endpoint is invoked, but before anything is written to the client.
 func ServerAfter(after ...ServerResponseFunc) ServerOption {
-	return func(s *Server) { s.after = after }
+	return func(s *Server) { s.after = append(s.after, after...) }
 }
 
 // ServerErrorEncoder is used to encode errors to the http.ResponseWriter

transport/http/server_test.go

@@ -93,6 +93,99 @@ func TestServerHappyPath(t *testing.T) {
 	}
 }
 
+
+func TestMultipleServerBefore(t *testing.T) {
+	var (
+		headerKey    = "X-Henlo-Lizer"
+		headerVal    = "Helllo you stinky lizard"
+		statusCode   = http.StatusTeapot
+		responseBody = "go eat a fly ugly\n"
+		done         = make(chan struct{})
+	)
+	handler := httptransport.NewServer(
+		context.Background(),
+		endpoint.Nop,
+		func(context.Context, *http.Request) (interface{}, error) {
+			return struct{}{}, nil
+		},
+		func(_ context.Context, w http.ResponseWriter, _ interface{}) error {
+			w.Header().Set(headerKey, headerVal)
+			w.WriteHeader(statusCode)
+			w.Write([]byte(responseBody))
+			return nil
+		},
+		httptransport.ServerBefore(func(ctx context.Context, r *http.Request) context.Context {
+			ctx = context.WithValue(ctx, "one", 1)
+
+			return ctx
+		}),
+		httptransport.ServerBefore(func(ctx context.Context, r *http.Request) context.Context {
+			if _, ok := ctx.Value("one").(int); !ok {
+				t.Error("Value was not set properly when multiple ServerBefores are used")
+			}
+
+			close(done)
+			return ctx
+		}),
+	)
+
+	server := httptest.NewServer(handler)
+	defer server.Close()
+	go http.Get(server.URL)
+
+	select {
+	case <-done:
+	case <-time.After(time.Second):
+		t.Fatal("timeout waiting for finalizer")
+	}
+}
+
+func TestMultipleServerAfter(t *testing.T) {
+	var (
+		headerKey    = "X-Henlo-Lizer"
+		headerVal    = "Helllo you stinky lizard"
+		statusCode   = http.StatusTeapot
+		responseBody = "go eat a fly ugly\n"
+		done         = make(chan struct{})
+	)
+	handler := httptransport.NewServer(
+		context.Background(),
+		endpoint.Nop,
+		func(context.Context, *http.Request) (interface{}, error) {
+			return struct{}{}, nil
+		},
+		func(_ context.Context, w http.ResponseWriter, _ interface{}) error {
+			w.Header().Set(headerKey, headerVal)
+			w.WriteHeader(statusCode)
+			w.Write([]byte(responseBody))
+			return nil
+		},
+		httptransport.ServerAfter(func(ctx context.Context, w http.ResponseWriter) context.Context {
+			ctx = context.WithValue(ctx, "one", 1)
+
+			return ctx
+		}),
+		httptransport.ServerAfter(func(ctx context.Context, w http.ResponseWriter) context.Context {
+			if _, ok := ctx.Value("one").(int); !ok {
+				t.Error("Value was not set properly when multiple ServerAfters are used")
+			}
+
+			close(done)
+			return ctx
+		}),
+	)
+
+	server := httptest.NewServer(handler)
+	defer server.Close()
+	go http.Get(server.URL)
+
+	select {
+	case <-done:
+	case <-time.After(time.Second):
+		t.Fatal("timeout waiting for finalizer")
+	}
+}
+
 func TestServerFinalizer(t *testing.T) {
 	var (
 		headerKey    = "X-Henlo-Lizer"

transport/httprp/server.go

@@ -45,7 +45,7 @@ type ServerOption func(*Server)
 // ServerBefore functions are executed on the HTTP request object before the
 // request is decoded.
 func ServerBefore(before ...RequestFunc) ServerOption {
-	return func(s *Server) { s.before = before }
+	return func(s *Server) { s.before = append(s.before, before...) }
 }
 
 // ServeHTTP implements http.Handler.

transport/httprp/server_test.go

@@ -119,3 +119,45 @@ func TestServerOriginServerUnreachable(t *testing.T) {
 		t.Errorf("want %d or %d, have %d", http.StatusBadGateway, http.StatusInternalServerError, resp.StatusCode)
 	}
 }
+
+func TestMultipleServerBefore(t *testing.T) {
+	const (
+		headerKey = "X-TEST-HEADER"
+		headerVal = "go-kit-proxy"
+	)
+
+	originServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if want, have := headerVal, r.Header.Get(headerKey); want != have {
+			t.Errorf("want %q, have %q", want, have)
+		}
+
+		w.WriteHeader(http.StatusOK)
+		w.Write([]byte("hey"))
+	}))
+	defer originServer.Close()
+	originURL, _ := url.Parse(originServer.URL)
+
+	handler := httptransport.NewServer(
+		context.Background(),
+		originURL,
+		httptransport.ServerBefore(func(ctx context.Context, r *http.Request) context.Context {
+			r.Header.Add(headerKey, headerVal)
+			return ctx
+		}),
+		httptransport.ServerBefore(func(ctx context.Context, r *http.Request) context.Context {
+			return ctx
+		}),
+	)
+	proxyServer := httptest.NewServer(handler)
+	defer proxyServer.Close()
+
+	resp, _ := http.Get(proxyServer.URL)
+	if want, have := http.StatusOK, resp.StatusCode; want != have {
+		t.Errorf("want %d, have %d", want, have)
+	}
+
+	responseBody, _ := ioutil.ReadAll(resp.Body)
+	if want, have := "hey", string(responseBody); want != have {
+		t.Errorf("want %q, have %q", want, have)
+	}
+}