diff --git a/api.go b/api.go
index 9485fca05..2198a0963 100644
--- a/api.go
+++ b/api.go
@@ -39,22 +39,28 @@ func httpError(w http.ResponseWriter, err error) {
 	}
 }
 
-func getAuth(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func writeJson(w http.ResponseWriter, b []byte) {
+	w.Header().Set("Content-Type", "application/json")
+	w.Write(b)
+}
+
+func getAuth(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	config := &auth.AuthConfig{
 		Username: srv.runtime.authConfig.Username,
 		Email:    srv.runtime.authConfig.Email,
 	}
 	b, err := json.Marshal(config)
 	if err != nil {
-		return nil, err
+		return err
 	}
-	return b, nil
+	writeJson(w, b)
+	return nil
 }
 
-func postAuth(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postAuth(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	config := &auth.AuthConfig{}
 	if err := json.NewDecoder(r.Body).Decode(config); err != nil {
-		return nil, err
+		return err
 	}
 
 	if config.Username == srv.runtime.authConfig.Username {
@@ -64,7 +70,7 @@ func postAuth(srv *Server, w http.ResponseWriter, r *http.Request, vars map[stri
 	newAuthConfig := auth.NewAuthConfig(config.Username, config.Password, config.Email, srv.runtime.root)
 	status, err := auth.Login(newAuthConfig)
 	if err != nil {
-		return nil, err
+		return err
 	} else {
 		srv.runtime.graph.getHttpClient().Jar = cookiejar.NewCookieJar()
 		srv.runtime.authConfig = newAuthConfig
@@ -72,38 +78,40 @@ func postAuth(srv *Server, w http.ResponseWriter, r *http.Request, vars map[stri
 	if status != "" {
 		b, err := json.Marshal(&ApiAuth{Status: status})
 		if err != nil {
-			return nil, err
+			return err
 		}
-		return b, nil
+		writeJson(w, b)
+		return nil
 	}
 	w.WriteHeader(http.StatusNoContent)
-	return nil, nil
+	return nil
 }
 
-func getVersion(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func getVersion(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	m := srv.DockerVersion()
 	b, err := json.Marshal(m)
 	if err != nil {
-		return nil, err
+		return err
 	}
-	return b, nil
+	writeJson(w, b)
+	return nil
 }
 
-func postContainersKill(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postContainersKill(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 	if err := srv.ContainerKill(name); err != nil {
-		return nil, err
+		return err
 	}
 	w.WriteHeader(http.StatusNoContent)
-	return nil, nil
+	return nil
 }
 
-func getContainersExport(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func getContainersExport(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 
@@ -111,12 +119,12 @@ func getContainersExport(srv *Server, w http.ResponseWriter, r *http.Request, va
 		Debugf("%s", err.Error())
 		//return nil, err
 	}
-	return nil, nil
+	return nil
 }
 
-func getImagesJson(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func getImagesJson(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if err := parseForm(r); err != nil {
-		return nil, err
+		return err
 	}
 
 	all := r.Form.Get("all") == "1"
@@ -125,66 +133,70 @@ func getImagesJson(srv *Server, w http.ResponseWriter, r *http.Request, vars map
 
 	outs, err := srv.Images(all, only_ids, filter)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	b, err := json.Marshal(outs)
 	if err != nil {
-		return nil, err
+		return err
 	}
-	return b, nil
+	writeJson(w, b)
+	return nil
 }
 
-func getImagesViz(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func getImagesViz(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if err := srv.ImagesViz(w); err != nil {
-		return nil, err
+		return err
 	}
-	return nil, nil
+	return nil
 }
 
-func getInfo(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func getInfo(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	out := srv.DockerInfo()
 	b, err := json.Marshal(out)
 	if err != nil {
-		return nil, err
+		return err
 	}
-	return b, nil
+	writeJson(w, b)
+	return nil
 }
 
-func getImagesHistory(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func getImagesHistory(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 	outs, err := srv.ImageHistory(name)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	b, err := json.Marshal(outs)
 	if err != nil {
-		return nil, err
+		return err
 	}
-	return b, nil
+	writeJson(w, b)
+	return nil
 }
 
-func getContainersChanges(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func getContainersChanges(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 	changesStr, err := srv.ContainerChanges(name)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	b, err := json.Marshal(changesStr)
 	if err != nil {
-		return nil, err
+		return err
 	}
-	return b, nil
+	writeJson(w, b)
+	return nil
 }
 
-func getContainersPs(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func getContainersPs(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if err := parseForm(r); err != nil {
-		return nil, err
+		return err
 	}
 	all := r.Form.Get("all") == "1"
 	trunc_cmd := r.Form.Get("trunc_cmd") != "0"
@@ -199,33 +211,34 @@ func getContainersPs(srv *Server, w http.ResponseWriter, r *http.Request, vars m
 	outs := srv.Containers(all, trunc_cmd, only_ids, n, since, before)
 	b, err := json.Marshal(outs)
 	if err != nil {
-		return nil, err
+		return err
 	}
-	return b, nil
+	writeJson(w, b)
+	return nil
 }
 
-func postImagesTag(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postImagesTag(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if err := parseForm(r); err != nil {
-		return nil, err
+		return err
 	}
 	repo := r.Form.Get("repo")
 	tag := r.Form.Get("tag")
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 	force := r.Form.Get("force") == "1"
 
 	if err := srv.ContainerTag(name, repo, tag, force); err != nil {
-		return nil, err
+		return err
 	}
 	w.WriteHeader(http.StatusCreated)
-	return nil, nil
+	return nil
 }
 
-func postCommit(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postCommit(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if err := parseForm(r); err != nil {
-		return nil, err
+		return err
 	}
 	config := &Config{}
 	if err := json.NewDecoder(r.Body).Decode(config); err != nil {
@@ -238,20 +251,21 @@ func postCommit(srv *Server, w http.ResponseWriter, r *http.Request, vars map[st
 	comment := r.Form.Get("comment")
 	id, err := srv.ContainerCommit(container, repo, tag, author, comment, config)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	b, err := json.Marshal(&ApiId{id})
 	if err != nil {
-		return nil, err
+		return err
 	}
 	w.WriteHeader(http.StatusCreated)
-	return b, nil
+	writeJson(w, b)
+	return nil
 }
 
 // Creates an image from Pull or from Import
-func postImagesCreate(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postImagesCreate(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if err := parseForm(r); err != nil {
-		return nil, err
+		return err
 	}
 
 	src := r.Form.Get("fromSrc")
@@ -261,7 +275,7 @@ func postImagesCreate(srv *Server, w http.ResponseWriter, r *http.Request, vars
 
 	in, out, err := hijackServer(w)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	defer in.Close()
 	fmt.Fprintf(out, "HTTP/1.1 200 OK\r\nContent-Type: application/vnd.docker.raw-stream\r\n\r\n")
@@ -275,95 +289,96 @@ func postImagesCreate(srv *Server, w http.ResponseWriter, r *http.Request, vars
 			fmt.Fprintf(out, "Error: %s\n", err)
 		}
 	}
-	return nil, nil
+	return nil
 }
 
-func getImagesSearch(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func getImagesSearch(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if err := parseForm(r); err != nil {
-		return nil, err
+		return err
 	}
 
 	term := r.Form.Get("term")
 	outs, err := srv.ImagesSearch(term)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	b, err := json.Marshal(outs)
 	if err != nil {
-		return nil, err
+		return err
 	}
-	return b, nil
+	writeJson(w, b)
+	return nil
 }
 
-func postImagesInsert(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postImagesInsert(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if err := parseForm(r); err != nil {
-		return nil, err
+		return err
 	}
 
 	url := r.Form.Get("url")
 	path := r.Form.Get("path")
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 
 	in, out, err := hijackServer(w)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	defer in.Close()
 	fmt.Fprintf(out, "HTTP/1.1 200 OK\r\nContent-Type: application/vnd.docker.raw-stream\r\n\r\n")
 	if err := srv.ImageInsert(name, url, path, out); err != nil {
 		fmt.Fprintf(out, "Error: %s\n", err)
 	}
-	return nil, nil
+	return nil
 }
 
-func postImagesPush(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postImagesPush(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if err := parseForm(r); err != nil {
-		return nil, err
+		return err
 	}
 
 	registry := r.Form.Get("registry")
 
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 
 	in, out, err := hijackServer(w)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	defer in.Close()
 	fmt.Fprintf(out, "HTTP/1.1 200 OK\r\nContent-Type: application/vnd.docker.raw-stream\r\n\r\n")
 	if err := srv.ImagePush(name, registry, out); err != nil {
 		fmt.Fprintln(out, "Error: %s\n", err)
 	}
-	return nil, nil
+	return nil
 }
 
-func postBuild(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postBuild(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	in, out, err := hijackServer(w)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	defer in.Close()
 	fmt.Fprintf(out, "HTTP/1.1 200 OK\r\nContent-Type: application/vnd.docker.raw-stream\r\n\r\n")
 	if err := srv.ImageCreateFromFile(in, out); err != nil {
 		fmt.Fprintln(out, "Error: %s\n", err)
 	}
-	return nil, nil
+	return nil
 }
 
-func postContainersCreate(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postContainersCreate(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	config := &Config{}
 	if err := json.NewDecoder(r.Body).Decode(config); err != nil {
-		return nil, err
+		return err
 	}
 	id, err := srv.ContainerCreate(config)
 	if err != nil {
-		return nil, err
+		return err
 	}
 
 	out := &ApiRun{
@@ -379,75 +394,76 @@ func postContainersCreate(srv *Server, w http.ResponseWriter, r *http.Request, v
 	}
 	b, err := json.Marshal(out)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	w.WriteHeader(http.StatusCreated)
-	return b, nil
+	writeJson(w, b)
+	return nil
 }
 
-func postContainersRestart(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postContainersRestart(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if err := parseForm(r); err != nil {
-		return nil, err
+		return err
 	}
 	t, err := strconv.Atoi(r.Form.Get("t"))
 	if err != nil || t < 0 {
 		t = 10
 	}
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 	if err := srv.ContainerRestart(name, t); err != nil {
-		return nil, err
+		return err
 	}
 	w.WriteHeader(http.StatusNoContent)
-	return nil, nil
+	return nil
 }
 
-func deleteContainers(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func deleteContainers(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if err := parseForm(r); err != nil {
-		return nil, err
+		return err
 	}
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 	removeVolume := r.Form.Get("v") == "1"
 
 	if err := srv.ContainerDestroy(name, removeVolume); err != nil {
-		return nil, err
+		return err
 	}
 	w.WriteHeader(http.StatusNoContent)
-	return nil, nil
+	return nil
 }
 
-func deleteImages(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func deleteImages(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 	if err := srv.ImageDelete(name); err != nil {
-		return nil, err
+		return err
 	}
 	w.WriteHeader(http.StatusNoContent)
-	return nil, nil
+	return nil
 }
 
-func postContainersStart(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postContainersStart(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 	if err := srv.ContainerStart(name); err != nil {
-		return nil, err
+		return err
 	}
 	w.WriteHeader(http.StatusNoContent)
-	return nil, nil
+	return nil
 }
 
-func postContainersStop(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postContainersStop(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if err := parseForm(r); err != nil {
-		return nil, err
+		return err
 	}
 	t, err := strconv.Atoi(r.Form.Get("t"))
 	if err != nil || t < 0 {
@@ -455,36 +471,37 @@ func postContainersStop(srv *Server, w http.ResponseWriter, r *http.Request, var
 	}
 
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 
 	if err := srv.ContainerStop(name, t); err != nil {
-		return nil, err
+		return err
 	}
 	w.WriteHeader(http.StatusNoContent)
-	return nil, nil
+	return nil
 }
 
-func postContainersWait(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postContainersWait(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 	status, err := srv.ContainerWait(name)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	b, err := json.Marshal(&ApiWait{StatusCode: status})
 	if err != nil {
-		return nil, err
+		return err
 	}
-	return b, nil
+	writeJson(w, b)
+	return nil
 }
 
-func postContainersAttach(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func postContainersAttach(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if err := parseForm(r); err != nil {
-		return nil, err
+		return err
 	}
 	logs := r.Form.Get("logs") == "1"
 	stream := r.Form.Get("stream") == "1"
@@ -492,13 +509,13 @@ func postContainersAttach(srv *Server, w http.ResponseWriter, r *http.Request, v
 	stdout := r.Form.Get("stdout") == "1"
 	stderr := r.Form.Get("stderr") == "1"
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 
 	in, out, err := hijackServer(w)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	defer in.Close()
 
@@ -506,48 +523,50 @@ func postContainersAttach(srv *Server, w http.ResponseWriter, r *http.Request, v
 	if err := srv.ContainerAttach(name, logs, stream, stdin, stdout, stderr, in, out); err != nil {
 		fmt.Fprintf(out, "Error: %s\n", err)
 	}
-	return nil, nil
+	return nil
 }
 
-func getContainersByName(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func getContainersByName(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 
 	container, err := srv.ContainerInspect(name)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	b, err := json.Marshal(container)
 	if err != nil {
-		return nil, err
+		return err
 	}
-	return b, nil
+	writeJson(w, b)
+	return nil
 }
 
-func getImagesByName(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) ([]byte, error) {
+func getImagesByName(srv *Server, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
 	if vars == nil {
-		return nil, fmt.Errorf("Missing parameter")
+		return fmt.Errorf("Missing parameter")
 	}
 	name := vars["name"]
 
 	image, err := srv.ImageInspect(name)
 	if err != nil {
-		return nil, err
+		return err
 	}
 	b, err := json.Marshal(image)
 	if err != nil {
-		return nil, err
+		return err
 	}
-	return b, nil
+	writeJson(w, b)
+	return nil
 }
 
 func ListenAndServe(addr string, srv *Server, logging bool) error {
 	r := mux.NewRouter()
 	log.Printf("Listening for HTTP on %s\n", addr)
 
-	m := map[string]map[string]func(*Server, http.ResponseWriter, *http.Request, map[string]string) ([]byte, error){
+	m := map[string]map[string]func(*Server, http.ResponseWriter, *http.Request, map[string]string) error{
 		"GET": {
 			"/auth":                         getAuth,
 			"/version":                      getVersion,
@@ -602,14 +621,9 @@ func ListenAndServe(addr string, srv *Server, logging bool) error {
 						Debugf("Warning: client and server don't have the same version (client: %s, server: %s)", userAgent[1], VERSION)
 					}
 				}
-				json, err := localFct(srv, w, r, mux.Vars(r))
-				if err != nil {
+				if err := localFct(srv, w, r, mux.Vars(r)); err != nil {
 					httpError(w, err)
 				}
-				if json != nil {
-					w.Header().Set("Content-Type", "application/json")
-					w.Write(json)
-				}
 			})
 		}
 	}
diff --git a/api_test.go b/api_test.go
index 1b139b7d6..68e60adc2 100644
--- a/api_test.go
+++ b/api_test.go
@@ -43,13 +43,9 @@ func TestGetAuth(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	body, err := postAuth(srv, r, req, nil)
-	if err != nil {
+	if err := postAuth(srv, r, req, nil); err != nil {
 		t.Fatal(err)
 	}
-	if body == nil {
-		t.Fatalf("No body received\n")
-	}
 	if r.Code != http.StatusOK && r.Code != 0 {
 		t.Fatalf("%d OK or 0 expected, received %d\n", http.StatusOK, r.Code)
 	}
@@ -70,15 +66,14 @@ func TestGetVersion(t *testing.T) {
 
 	srv := &Server{runtime: runtime}
 
-	body, err := getVersion(srv, nil, nil, nil)
-	if err != nil {
+	r := httptest.NewRecorder()
+
+	if err := getVersion(srv, r, nil, nil); err != nil {
 		t.Fatal(err)
 	}
 
 	v := &ApiVersion{}
-
-	err = json.Unmarshal(body, v)
-	if err != nil {
+	if err = json.Unmarshal(r.Body.Bytes(), v); err != nil {
 		t.Fatal(err)
 	}
 	if v.Version != VERSION {
@@ -95,12 +90,14 @@ func TestGetInfo(t *testing.T) {
 
 	srv := &Server{runtime: runtime}
 
-	body, err := getInfo(srv, nil, nil, nil)
-	if err != nil {
+	r := httptest.NewRecorder()
+
+	if err := getInfo(srv, r, nil, nil); err != nil {
 		t.Fatal(err)
 	}
+
 	infos := &ApiInfo{}
-	err = json.Unmarshal(body, infos)
+	err = json.Unmarshal(r.Body.Bytes(), infos)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -124,14 +121,14 @@ func TestGetImagesJson(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	body, err := getImagesJson(srv, nil, req, nil)
-	if err != nil {
+	r := httptest.NewRecorder()
+
+	if err := getImagesJson(srv, r, req, nil); err != nil {
 		t.Fatal(err)
 	}
 
 	images := []ApiImages{}
-	err = json.Unmarshal(body, &images)
-	if err != nil {
+	if err := json.Unmarshal(r.Body.Bytes(), &images); err != nil {
 		t.Fatal(err)
 	}
 
@@ -143,20 +140,20 @@ func TestGetImagesJson(t *testing.T) {
 		t.Errorf("Excepted image %s, %s found", unitTestImageName, images[0].Repository)
 	}
 
+	r2 := httptest.NewRecorder()
+
 	// only_ids=1&all=1
 	req2, err := http.NewRequest("GET", "/images/json?only_ids=1&all=1", nil)
 	if err != nil {
 		t.Fatal(err)
 	}
 
-	body2, err := getImagesJson(srv, nil, req2, nil)
-	if err != nil {
+	if err := getImagesJson(srv, r2, req2, nil); err != nil {
 		t.Fatal(err)
 	}
 
 	images2 := []ApiImages{}
-	err = json.Unmarshal(body2, &images2)
-	if err != nil {
+	if err := json.Unmarshal(r2.Body.Bytes(), &images2); err != nil {
 		t.Fatal(err)
 	}
 
@@ -172,20 +169,20 @@ func TestGetImagesJson(t *testing.T) {
 		t.Errorf("Retrieved image Id differs, expected %s, received %s", GetTestImage(runtime).ShortId(), images2[0].Id)
 	}
 
+	r3 := httptest.NewRecorder()
+
 	// filter=a
 	req3, err := http.NewRequest("GET", "/images/json?filter=a", nil)
 	if err != nil {
 		t.Fatal(err)
 	}
 
-	body3, err := getImagesJson(srv, nil, req3, nil)
-	if err != nil {
+	if err := getImagesJson(srv, r3, req3, nil); err != nil {
 		t.Fatal(err)
 	}
 
 	images3 := []ApiImages{}
-	err = json.Unmarshal(body3, &images3)
-	if err != nil {
+	if err := json.Unmarshal(r3.Body.Bytes(), &images3); err != nil {
 		t.Fatal(err)
 	}
 
@@ -204,9 +201,7 @@ func TestGetImagesViz(t *testing.T) {
 	srv := &Server{runtime: runtime}
 
 	r := httptest.NewRecorder()
-
-	_, err = getImagesViz(srv, r, nil, nil)
-	if err != nil {
+	if err := getImagesViz(srv, r, nil, nil); err != nil {
 		t.Fatal(err)
 	}
 
@@ -233,19 +228,19 @@ func TestGetImagesSearch(t *testing.T) {
 
 	srv := &Server{runtime: runtime}
 
+	r := httptest.NewRecorder()
+
 	req, err := http.NewRequest("GET", "/images/search?term=redis", nil)
 	if err != nil {
 		t.Fatal(err)
 	}
 
-	body, err := getImagesSearch(srv, nil, req, nil)
-	if err != nil {
+	if err := getImagesSearch(srv, r, req, nil); err != nil {
 		t.Fatal(err)
 	}
 
 	results := []ApiSearch{}
-	err = json.Unmarshal(body, &results)
-	if err != nil {
+	if err := json.Unmarshal(r.Body.Bytes(), &results); err != nil {
 		t.Fatal(err)
 	}
 	if len(results) < 2 {
@@ -262,14 +257,14 @@ func TestGetImagesHistory(t *testing.T) {
 
 	srv := &Server{runtime: runtime}
 
-	body, err := getImagesHistory(srv, nil, nil, map[string]string{"name": unitTestImageName})
-	if err != nil {
+	r := httptest.NewRecorder()
+
+	if err := getImagesHistory(srv, r, nil, map[string]string{"name": unitTestImageName}); err != nil {
 		t.Fatal(err)
 	}
 
 	history := []ApiHistory{}
-	err = json.Unmarshal(body, &history)
-	if err != nil {
+	if err := json.Unmarshal(r.Body.Bytes(), &history); err != nil {
 		t.Fatal(err)
 	}
 	if len(history) != 1 {
@@ -286,15 +281,13 @@ func TestGetImagesByName(t *testing.T) {
 
 	srv := &Server{runtime: runtime}
 
-	body, err := getImagesByName(srv, nil, nil, map[string]string{"name": unitTestImageName})
-	if err != nil {
+	r := httptest.NewRecorder()
+	if err := getImagesByName(srv, r, nil, map[string]string{"name": unitTestImageName}); err != nil {
 		t.Fatal(err)
 	}
 
 	img := &Image{}
-
-	err = json.Unmarshal(body, img)
-	if err != nil {
+	if err := json.Unmarshal(r.Body.Bytes(), img); err != nil {
 		t.Fatal(err)
 	}
 	if img.Id != GetTestImage(runtime).Id || img.Comment != "Imported from http://get.docker.io/images/busybox" {
@@ -325,13 +318,12 @@ func TestGetContainersPs(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	body, err := getContainersPs(srv, nil, req, nil)
-	if err != nil {
+	r := httptest.NewRecorder()
+	if err := getContainersPs(srv, r, req, nil); err != nil {
 		t.Fatal(err)
 	}
 	containers := []ApiContainers{}
-	err = json.Unmarshal(body, &containers)
-	if err != nil {
+	if err := json.Unmarshal(r.Body.Bytes(), &containers); err != nil {
 		t.Fatal(err)
 	}
 	if len(containers) != 1 {
@@ -370,9 +362,7 @@ func TestGetContainersExport(t *testing.T) {
 	}
 
 	r := httptest.NewRecorder()
-
-	_, err = getContainersExport(srv, r, nil, map[string]string{"name": container.Id})
-	if err != nil {
+	if err = getContainersExport(srv, r, nil, map[string]string{"name": container.Id}); err != nil {
 		t.Fatal(err)
 	}
 
@@ -426,12 +416,12 @@ func TestGetContainersChanges(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	body, err := getContainersChanges(srv, nil, nil, map[string]string{"name": container.Id})
-	if err != nil {
+	r := httptest.NewRecorder()
+	if err := getContainersChanges(srv, r, nil, map[string]string{"name": container.Id}); err != nil {
 		t.Fatal(err)
 	}
 	changes := []Change{}
-	if err := json.Unmarshal(body, &changes); err != nil {
+	if err := json.Unmarshal(r.Body.Bytes(), &changes); err != nil {
 		t.Fatal(err)
 	}
 
@@ -470,12 +460,12 @@ func TestGetContainersByName(t *testing.T) {
 	}
 	defer runtime.Destroy(container)
 
-	body, err := getContainersByName(srv, nil, nil, map[string]string{"name": container.Id})
-	if err != nil {
+	r := httptest.NewRecorder()
+	if err := getContainersByName(srv, r, nil, map[string]string{"name": container.Id}); err != nil {
 		t.Fatal(err)
 	}
 	outContainer := &Container{}
-	if err := json.Unmarshal(body, outContainer); err != nil {
+	if err := json.Unmarshal(r.Body.Bytes(), outContainer); err != nil {
 		t.Fatal(err)
 	}
 	if outContainer.Id != container.Id {
@@ -498,14 +488,13 @@ func TestPostAuth(t *testing.T) {
 	}
 	runtime.authConfig = authConfigOrig
 
-	body, err := getAuth(srv, nil, nil, nil)
-	if err != nil {
+	r := httptest.NewRecorder()
+	if err := getAuth(srv, r, nil, nil); err != nil {
 		t.Fatal(err)
 	}
 
 	authConfig := &auth.AuthConfig{}
-	err = json.Unmarshal(body, authConfig)
-	if err != nil {
+	if err := json.Unmarshal(r.Body.Bytes(), authConfig); err != nil {
 		t.Fatal(err)
 	}
 
@@ -523,8 +512,6 @@ func TestPostCommit(t *testing.T) {
 
 	srv := &Server{runtime: runtime}
 
-	r := httptest.NewRecorder()
-
 	builder := NewBuilder(runtime)
 
 	// Create a container and remove a file
@@ -548,8 +535,8 @@ func TestPostCommit(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	body, err := postCommit(srv, r, req, nil)
-	if err != nil {
+	r := httptest.NewRecorder()
+	if err := postCommit(srv, r, req, nil); err != nil {
 		t.Fatal(err)
 	}
 	if r.Code != http.StatusCreated {
@@ -557,7 +544,7 @@ func TestPostCommit(t *testing.T) {
 	}
 
 	apiId := &ApiId{}
-	if err := json.Unmarshal(body, apiId); err != nil {
+	if err := json.Unmarshal(r.Body.Bytes(), apiId); err != nil {
 		t.Fatal(err)
 	}
 	if _, err := runtime.graph.Get(apiId.Id); err != nil {
@@ -579,20 +566,16 @@ func TestPostBuild(t *testing.T) {
 
 	c1 := make(chan struct{})
 	go func() {
+		defer close(c1)
 		r := &hijackTester{
 			ResponseRecorder: httptest.NewRecorder(),
 			in:               stdin,
 			out:              stdoutPipe,
 		}
 
-		body, err := postBuild(srv, r, nil, nil)
-		close(c1)
-		if err != nil {
+		if err := postBuild(srv, r, nil, nil); err != nil {
 			t.Fatal(err)
 		}
-		if body != nil {
-			t.Fatalf("No body expected, received: %s\n", body)
-		}
 	}()
 
 	// Acknowledge hijack
@@ -794,8 +777,6 @@ func TestPostContainersCreate(t *testing.T) {
 
 	srv := &Server{runtime: runtime}
 
-	r := httptest.NewRecorder()
-
 	configJson, err := json.Marshal(&Config{
 		Image:  GetTestImage(runtime).Id,
 		Memory: 33554432,
@@ -810,8 +791,8 @@ func TestPostContainersCreate(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	body, err := postContainersCreate(srv, r, req, nil)
-	if err != nil {
+	r := httptest.NewRecorder()
+	if err := postContainersCreate(srv, r, req, nil); err != nil {
 		t.Fatal(err)
 	}
 	if r.Code != http.StatusCreated {
@@ -819,7 +800,7 @@ func TestPostContainersCreate(t *testing.T) {
 	}
 
 	apiRun := &ApiRun{}
-	if err := json.Unmarshal(body, apiRun); err != nil {
+	if err := json.Unmarshal(r.Body.Bytes(), apiRun); err != nil {
 		t.Fatal(err)
 	}
 
@@ -874,14 +855,9 @@ func TestPostContainersKill(t *testing.T) {
 	}
 
 	r := httptest.NewRecorder()
-
-	body, err := postContainersKill(srv, r, nil, map[string]string{"name": container.Id})
-	if err != nil {
+	if err := postContainersKill(srv, r, nil, map[string]string{"name": container.Id}); err != nil {
 		t.Fatal(err)
 	}
-	if body != nil {
-		t.Fatalf("No body expected, received: %s\n", body)
-	}
 	if r.Code != http.StatusNoContent {
 		t.Fatalf("%d NO CONTENT expected, received %d\n", http.StatusNoContent, r.Code)
 	}
@@ -922,19 +898,14 @@ func TestPostContainersRestart(t *testing.T) {
 		t.Errorf("Container should be running")
 	}
 
-	r := httptest.NewRecorder()
-
 	req, err := http.NewRequest("POST", "/containers/"+container.Id+"/restart?t=1", bytes.NewReader([]byte{}))
 	if err != nil {
 		t.Fatal(err)
 	}
-	body, err := postContainersRestart(srv, r, req, map[string]string{"name": container.Id})
-	if err != nil {
+	r := httptest.NewRecorder()
+	if err := postContainersRestart(srv, r, req, map[string]string{"name": container.Id}); err != nil {
 		t.Fatal(err)
 	}
-	if body != nil {
-		t.Fatalf("No body expected, received: %s\n", body)
-	}
 	if r.Code != http.StatusNoContent {
 		t.Fatalf("%d NO CONTENT expected, received %d\n", http.StatusNoContent, r.Code)
 	}
@@ -973,14 +944,9 @@ func TestPostContainersStart(t *testing.T) {
 	defer runtime.Destroy(container)
 
 	r := httptest.NewRecorder()
-
-	body, err := postContainersStart(srv, r, nil, map[string]string{"name": container.Id})
-	if err != nil {
+	if err := postContainersStart(srv, r, nil, map[string]string{"name": container.Id}); err != nil {
 		t.Fatal(err)
 	}
-	if body != nil {
-		t.Fatalf("No body expected, received: %s\n", body)
-	}
 	if r.Code != http.StatusNoContent {
 		t.Fatalf("%d NO CONTENT expected, received %d\n", http.StatusNoContent, r.Code)
 	}
@@ -992,7 +958,8 @@ func TestPostContainersStart(t *testing.T) {
 		t.Errorf("Container should be running")
 	}
 
-	if _, err = postContainersStart(srv, r, nil, map[string]string{"name": container.Id}); err == nil {
+	r = httptest.NewRecorder()
+	if err = postContainersStart(srv, r, nil, map[string]string{"name": container.Id}); err == nil {
 		t.Fatalf("A running containter should be able to be started")
 	}
 
@@ -1033,20 +1000,15 @@ func TestPostContainersStop(t *testing.T) {
 		t.Errorf("Container should be running")
 	}
 
-	r := httptest.NewRecorder()
-
 	// Note: as it is a POST request, it requires a body.
 	req, err := http.NewRequest("POST", "/containers/"+container.Id+"/stop?t=1", bytes.NewReader([]byte{}))
 	if err != nil {
 		t.Fatal(err)
 	}
-	body, err := postContainersStop(srv, r, req, map[string]string{"name": container.Id})
-	if err != nil {
+	r := httptest.NewRecorder()
+	if err := postContainersStop(srv, r, req, map[string]string{"name": container.Id}); err != nil {
 		t.Fatal(err)
 	}
-	if body != nil {
-		t.Fatalf("No body expected, received: %s\n", body)
-	}
 	if r.Code != http.StatusNoContent {
 		t.Fatalf("%d NO CONTENT expected, received %d\n", http.StatusNoContent, r.Code)
 	}
@@ -1081,12 +1043,12 @@ func TestPostContainersWait(t *testing.T) {
 	}
 
 	setTimeout(t, "Wait timed out", 3*time.Second, func() {
-		body, err := postContainersWait(srv, nil, nil, map[string]string{"name": container.Id})
-		if err != nil {
+		r := httptest.NewRecorder()
+		if err := postContainersWait(srv, r, nil, map[string]string{"name": container.Id}); err != nil {
 			t.Fatal(err)
 		}
 		apiWait := &ApiWait{}
-		if err := json.Unmarshal(body, apiWait); err != nil {
+		if err := json.Unmarshal(r.Body.Bytes(), apiWait); err != nil {
 			t.Fatal(err)
 		}
 		if apiWait.StatusCode != 0 {
@@ -1131,8 +1093,7 @@ func TestPostContainersAttach(t *testing.T) {
 	// Attach to it
 	c1 := make(chan struct{})
 	go func() {
-		// We're simulating a disconnect so the return value doesn't matter. What matters is the
-		// fact that CmdAttach returns.
+		defer close(c1)
 
 		r := &hijackTester{
 			ResponseRecorder: httptest.NewRecorder(),
@@ -1145,14 +1106,9 @@ func TestPostContainersAttach(t *testing.T) {
 			t.Fatal(err)
 		}
 
-		body, err := postContainersAttach(srv, r, req, map[string]string{"name": container.Id})
-		close(c1)
-		if err != nil {
+		if err := postContainersAttach(srv, r, req, map[string]string{"name": container.Id}); err != nil {
 			t.Fatal(err)
 		}
-		if body != nil {
-			t.Fatalf("No body expected, received: %s\n", body)
-		}
 	}()
 
 	// Acknowledge hijack
@@ -1215,20 +1171,14 @@ func TestDeleteContainers(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	r := httptest.NewRecorder()
-
 	req, err := http.NewRequest("DELETE", "/containers/"+container.Id, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
-
-	body, err := deleteContainers(srv, r, req, map[string]string{"name": container.Id})
-	if err != nil {
+	r := httptest.NewRecorder()
+	if err := deleteContainers(srv, r, req, map[string]string{"name": container.Id}); err != nil {
 		t.Fatal(err)
 	}
-	if body != nil {
-		t.Fatalf("No body expected, received: %s\n", body)
-	}
 	if r.Code != http.StatusNoContent {
 		t.Fatalf("%d NO CONTENT expected, received %d\n", http.StatusNoContent, r.Code)
 	}
@@ -1244,7 +1194,7 @@ func TestDeleteContainers(t *testing.T) {
 
 func TestDeleteImages(t *testing.T) {
 	//FIXME: Implement this test
-	t.Log("Test not implemented")
+	t.Skip("Test not implemented")
 }
 
 // Mocked types for tests