From 259e65cd518a0b54e48515f927f46e6ff97f79f8 Mon Sep 17 00:00:00 2001
From: Julian Dolce <jdolce@qnx.com>
Date: Fri, 2 Feb 2018 12:08:24 -0500
Subject: [PATCH] HTTP server NoOpRequestDecoder

Adds NoOpRequestDecoder for HTTP request that do not need to be decoded.

Fixes #657
---
 transport/http/server.go      |  6 ++++++
 transport/http/server_test.go | 22 ++++++++++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/transport/http/server.go b/transport/http/server.go
index 13a27d958..183009d22 100644
--- a/transport/http/server.go
+++ b/transport/http/server.go
@@ -136,6 +136,12 @@ type ErrorEncoder func(ctx context.Context, err error, w http.ResponseWriter)
 // provided in the context under keys with the ContextKeyResponse prefix.
 type ServerFinalizerFunc func(ctx context.Context, code int, r *http.Request)
 
+// NopRequestDecoder is a DecodeRequestFunc that can be used for requests that do not
+// need to be decoded, and simply returns nil, nil.
+func NopRequestDecoder(ctx context.Context, r *http.Request) (interface{}, error) {
+	return nil, nil
+}
+
 // EncodeJSONResponse is a EncodeResponseFunc that serializes the response as a
 // JSON object to the ResponseWriter. Many JSON-over-HTTP services can use it as
 // a sensible default. If the response implements Headerer, the provided headers
diff --git a/transport/http/server_test.go b/transport/http/server_test.go
index 20a077811..c4359272e 100644
--- a/transport/http/server_test.go
+++ b/transport/http/server_test.go
@@ -393,6 +393,28 @@ func TestEnhancedError(t *testing.T) {
 	}
 }
 
+func TestNoOpRequestDecoder(t *testing.T) {
+	resw := httptest.NewRecorder()
+	req, err := http.NewRequest(http.MethodGet, "/", nil)
+	if err != nil {
+		t.Error("Failed to create request")
+	}
+	handler := httptransport.NewServer(
+		func(ctx context.Context, request interface{}) (interface{}, error) {
+			if request != nil {
+				t.Error("Expected nil request in endpoint when using NopRequestDecoder")
+			}
+			return nil, nil
+		},
+		httptransport.NopRequestDecoder,
+		httptransport.EncodeJSONResponse,
+	)
+	handler.ServeHTTP(resw, req)
+	if resw.Code != http.StatusOK {
+		t.Errorf("Expected status code %d but got %d", http.StatusOK, resw.Code)
+	}
+}
+
 func testServer(t *testing.T) (step func(), resp <-chan *http.Response) {
 	var (
 		stepch   = make(chan bool)