@@ -33,7 +33,7 @@ func loginV1(authConfig *types.AuthConfig, apiEndpoint APIEndpoint, userAgent st

 		return "", "", errdefs.System(errors.New("server Error: Server Address not set"))

 	}

-	req, err := http.NewRequest("GET", serverAddress+"users/", nil)

+	req, err := http.NewRequest(http.MethodGet, serverAddress+"users/", nil)

 	if err != nil {

 		return "", "", err

 	}

@@ -140,7 +140,7 @@ func loginV2(authConfig *types.AuthConfig, endpoint APIEndpoint, userAgent strin

 	}

 	endpointStr := strings.TrimRight(endpoint.URL.String(), "/") + "/v2/"

-	req, err := http.NewRequest("GET", endpointStr, nil)

+	req, err := http.NewRequest(http.MethodGet, endpointStr, nil)

 	if err != nil {

 		if !foundV2 {

 			err = fallbackError{err: err}

@@ -262,7 +262,7 @@ func PingV2Registry(endpoint *url.URL, transport http.RoundTripper) (challenge.M

 		Timeout:   15 * time.Second,

 	}

 	endpointStr := strings.TrimRight(endpoint.String(), "/") + "/v2/"

-	req, err := http.NewRequest("GET", endpointStr, nil)

+	req, err := http.NewRequest(http.MethodGet, endpointStr, nil)

 	if err != nil {

 		return nil, false, err

 	}

@@ -149,7 +149,7 @@ func (e *V1Endpoint) Ping() (PingResult, error) {

 		return PingResult{Standalone: false}, nil

 	}

-	req, err := http.NewRequest("GET", e.Path("_ping"), nil)

+	req, err := http.NewRequest(http.MethodGet, e.Path("_ping"), nil)

 	if err != nil {

 		return PingResult{Standalone: false}, err

 	}

@@ -97,19 +97,19 @@ func init() {

 	r := mux.NewRouter()

 	// /v1/

-	r.HandleFunc("/v1/_ping", handlerGetPing).Methods("GET")

-	r.HandleFunc("/v1/images/{image_id:[^/]+}/{action:json|layer|ancestry}", handlerGetImage).Methods("GET")

-	r.HandleFunc("/v1/images/{image_id:[^/]+}/{action:json|layer|checksum}", handlerPutImage).Methods("PUT")

-	r.HandleFunc("/v1/repositories/{repository:.+}/tags", handlerGetDeleteTags).Methods("GET", "DELETE")

-	r.HandleFunc("/v1/repositories/{repository:.+}/tags/{tag:.+}", handlerGetTag).Methods("GET")

-	r.HandleFunc("/v1/repositories/{repository:.+}/tags/{tag:.+}", handlerPutTag).Methods("PUT")

-	r.HandleFunc("/v1/users{null:.*}", handlerUsers).Methods("GET", "POST", "PUT")

-	r.HandleFunc("/v1/repositories/{repository:.+}{action:/images|/}", handlerImages).Methods("GET", "PUT", "DELETE")

-	r.HandleFunc("/v1/repositories/{repository:.+}/auth", handlerAuth).Methods("PUT")

-	r.HandleFunc("/v1/search", handlerSearch).Methods("GET")

+	r.HandleFunc("/v1/_ping", handlerGetPing).Methods(http.MethodGet)

+	r.HandleFunc("/v1/images/{image_id:[^/]+}/{action:json|layer|ancestry}", handlerGetImage).Methods(http.MethodGet)

+	r.HandleFunc("/v1/images/{image_id:[^/]+}/{action:json|layer|checksum}", handlerPutImage).Methods(http.MethodPut)

+	r.HandleFunc("/v1/repositories/{repository:.+}/tags", handlerGetDeleteTags).Methods(http.MethodGet, http.MethodDelete)

+	r.HandleFunc("/v1/repositories/{repository:.+}/tags/{tag:.+}", handlerGetTag).Methods(http.MethodGet)

+	r.HandleFunc("/v1/repositories/{repository:.+}/tags/{tag:.+}", handlerPutTag).Methods(http.MethodPut)

+	r.HandleFunc("/v1/users{null:.*}", handlerUsers).Methods(http.MethodGet, http.MethodPost, http.MethodPut)

+	r.HandleFunc("/v1/repositories/{repository:.+}{action:/images|/}", handlerImages).Methods(http.MethodGet, http.MethodPut, http.MethodDelete)

+	r.HandleFunc("/v1/repositories/{repository:.+}/auth", handlerAuth).Methods(http.MethodPut)

+	r.HandleFunc("/v1/search", handlerSearch).Methods(http.MethodGet)

 	// /v2/

-	r.HandleFunc("/v2/version", handlerGetPing).Methods("GET")

+	r.HandleFunc("/v2/version", handlerGetPing).Methods(http.MethodGet)

 	testHTTPServer = httptest.NewServer(handlerAccessLog(r))

 	testHTTPSServer = httptest.NewTLSServer(handlerAccessLog(r))

@@ -350,7 +350,7 @@ func handlerGetDeleteTags(w http.ResponseWriter, r *http.Request) {

 		apiError(w, "Repository not found", 404)

 		return

 	}

-	if r.Method == "DELETE" {

+	if r.Method == http.MethodDelete {

 		delete(testRepositories, repositoryName.String())

 		writeResponse(w, true, 200)

 		return

@@ -406,9 +406,9 @@ func handlerPutTag(w http.ResponseWriter, r *http.Request) {

 func handlerUsers(w http.ResponseWriter, r *http.Request) {

 	code := 200

-	if r.Method == "POST" {

+	if r.Method == http.MethodPost {

 		code = 201

-	} else if r.Method == "PUT" {

+	} else if r.Method == http.MethodPut {

 		code = 204

 	}

 	writeResponse(w, "", code)

@@ -418,7 +418,7 @@ func handlerImages(w http.ResponseWriter, r *http.Request) {

 	u, _ := url.Parse(testHTTPServer.URL)

 	w.Header().Add("X-Docker-Endpoints", fmt.Sprintf("%s 	,  %s ", u.Host, "test.example.com"))

 	w.Header().Add("X-Docker-Token", fmt.Sprintf("FAKE-SESSION-%d", time.Now().UnixNano()))

-	if r.Method == "PUT" {

+	if r.Method == http.MethodPut {

 		if strings.HasSuffix(r.URL.Path, "images") {

 			writeResponse(w, "", 204)

 			return

@@ -426,7 +426,7 @@ func handlerImages(w http.ResponseWriter, r *http.Request) {

 		writeResponse(w, "", 200)

 		return

 	}

-	if r.Method == "DELETE" {

+	if r.Method == http.MethodDelete {

 		writeResponse(w, "", 204)

 		return

 	}

@@ -761,12 +761,12 @@ func TestSearchRepositories(t *testing.T) {

 func TestTrustedLocation(t *testing.T) {

 	for _, url := range []string{"http://example.com", "https://example.com:7777", "http://docker.io", "http://test.docker.com", "https://fakedocker.com"} {

-		req, _ := http.NewRequest("GET", url, nil)

+		req, _ := http.NewRequest(http.MethodGet, url, nil)

 		assert.Check(t, !trustedLocation(req))

 	}

 	for _, url := range []string{"https://docker.io", "https://test.docker.com:80"} {

-		req, _ := http.NewRequest("GET", url, nil)

+		req, _ := http.NewRequest(http.MethodGet, url, nil)

 		assert.Check(t, trustedLocation(req))

 	}

 }

@@ -777,10 +777,10 @@ func TestAddRequiredHeadersToRedirectedRequests(t *testing.T) {

 		{"https://foo.docker.io:7777", "http://bar.docker.com"},

 		{"https://foo.docker.io", "https://example.com"},

 	} {

-		reqFrom, _ := http.NewRequest("GET", urls[0], nil)

+		reqFrom, _ := http.NewRequest(http.MethodGet, urls[0], nil)

 		reqFrom.Header.Add("Content-Type", "application/json")

 		reqFrom.Header.Add("Authorization", "super_secret")

-		reqTo, _ := http.NewRequest("GET", urls[1], nil)

+		reqTo, _ := http.NewRequest(http.MethodGet, urls[1], nil)

 		addRequiredHeadersToRedirectedRequests(reqTo, []*http.Request{reqFrom})

@@ -801,10 +801,10 @@ func TestAddRequiredHeadersToRedirectedRequests(t *testing.T) {

 		{"https://docker.io", "https://docker.com"},

 		{"https://foo.docker.io:7777", "https://bar.docker.com"},

 	} {

-		reqFrom, _ := http.NewRequest("GET", urls[0], nil)

+		reqFrom, _ := http.NewRequest(http.MethodGet, urls[0], nil)

 		reqFrom.Header.Add("Content-Type", "application/json")

 		reqFrom.Header.Add("Authorization", "super_secret")

-		reqTo, _ := http.NewRequest("GET", urls[1], nil)

+		reqTo, _ := http.NewRequest(http.MethodGet, urls[1], nil)

 		addRequiredHeadersToRedirectedRequests(reqTo, []*http.Request{reqFrom})

@@ -23,7 +23,7 @@ func TestResumableRequestHeaderSimpleErrors(t *testing.T) {

 	client := &http.Client{}

 	var req *http.Request

-	req, err := http.NewRequest("GET", ts.URL, nil)

+	req, err := http.NewRequest(http.MethodGet, ts.URL, nil)

 	assert.NilError(t, err)

 	resreq := &requestReader{}

@@ -44,7 +44,7 @@ func TestResumableRequestHeaderNotTooMuchFailures(t *testing.T) {

 	client := &http.Client{}

 	var badReq *http.Request

-	badReq, err := http.NewRequest("GET", "I'm not an url", nil)

+	badReq, err := http.NewRequest(http.MethodGet, "I'm not an url", nil)

 	assert.NilError(t, err)

 	resreq := &requestReader{

@@ -64,7 +64,7 @@ func TestResumableRequestHeaderTooMuchFailures(t *testing.T) {

 	client := &http.Client{}

 	var badReq *http.Request

-	badReq, err := http.NewRequest("GET", "I'm not an url", nil)

+	badReq, err := http.NewRequest(http.MethodGet, "I'm not an url", nil)

 	assert.NilError(t, err)

 	resreq := &requestReader{

@@ -92,7 +92,7 @@ func (errorReaderCloser) Read(p []byte) (n int, err error) {

 // If an unknown error is encountered, return 0, nil and log it

 func TestResumableRequestReaderWithReadError(t *testing.T) {

 	var req *http.Request

-	req, err := http.NewRequest("GET", "", nil)

+	req, err := http.NewRequest(http.MethodGet, "", nil)

 	assert.NilError(t, err)

 	client := &http.Client{}

@@ -123,7 +123,7 @@ func TestResumableRequestReaderWithReadError(t *testing.T) {

 func TestResumableRequestReaderWithEOFWith416Response(t *testing.T) {

 	var req *http.Request

-	req, err := http.NewRequest("GET", "", nil)

+	req, err := http.NewRequest(http.MethodGet, "", nil)

 	assert.NilError(t, err)

 	client := &http.Client{}

@@ -159,7 +159,7 @@ func TestResumableRequestReaderWithServerDoesntSupportByteRanges(t *testing.T) {

 	defer ts.Close()

 	var req *http.Request

-	req, err := http.NewRequest("GET", ts.URL, nil)

+	req, err := http.NewRequest(http.MethodGet, ts.URL, nil)

 	assert.NilError(t, err)

 	client := &http.Client{}

@@ -185,7 +185,7 @@ func TestResumableRequestReaderWithZeroTotalSize(t *testing.T) {

 	defer ts.Close()

 	var req *http.Request

-	req, err := http.NewRequest("GET", ts.URL, nil)

+	req, err := http.NewRequest(http.MethodGet, ts.URL, nil)

 	assert.NilError(t, err)

 	client := &http.Client{}

@@ -210,7 +210,7 @@ func TestResumableRequestReader(t *testing.T) {

 	defer ts.Close()

 	var req *http.Request

-	req, err := http.NewRequest("GET", ts.URL, nil)

+	req, err := http.NewRequest(http.MethodGet, ts.URL, nil)

 	assert.NilError(t, err)

 	client := &http.Client{}

@@ -236,7 +236,7 @@ func TestResumableRequestReaderWithInitialResponse(t *testing.T) {

 	defer ts.Close()

 	var req *http.Request

-	req, err := http.NewRequest("GET", ts.URL, nil)

+	req, err := http.NewRequest(http.MethodGet, ts.URL, nil)

 	assert.NilError(t, err)

 	client := &http.Client{}

@@ -289,7 +289,7 @@ func (r *Session) GetRemoteImageLayer(imgID, registry string, imgSize int64) (io

 		imageURL   = fmt.Sprintf("%simages/%s/layer", registry, imgID)

 	)

-	req, err := http.NewRequest("GET", imageURL, nil)

+	req, err := http.NewRequest(http.MethodGet, imageURL, nil)

 	if err != nil {

 		return nil, fmt.Errorf("Error while getting from the server: %v", err)

 	}

@@ -423,7 +423,7 @@ func (r *Session) GetRepositoryData(name reference.Named) (*RepositoryData, erro

 	logrus.Debugf("[registry] Calling GET %s", repositoryTarget)

-	req, err := http.NewRequest("GET", repositoryTarget, nil)

+	req, err := http.NewRequest(http.MethodGet, repositoryTarget, nil)

 	if err != nil {

 		return nil, err

 	}

@@ -490,7 +490,7 @@ func (r *Session) PushImageChecksumRegistry(imgData *ImgData, registry string) e

 	logrus.Debugf("[registry] Calling PUT %s", u)

-	req, err := http.NewRequest("PUT", u, nil)

+	req, err := http.NewRequest(http.MethodPut, u, nil)

 	if err != nil {

 		return err

 	}

@@ -528,7 +528,7 @@ func (r *Session) PushImageJSONRegistry(imgData *ImgData, jsonRaw []byte, regist

 	logrus.Debugf("[registry] Calling PUT %s", u)

-	req, err := http.NewRequest("PUT", u, bytes.NewReader(jsonRaw))

+	req, err := http.NewRequest(http.MethodPut, u, bytes.NewReader(jsonRaw))

 	if err != nil {

 		return err

 	}

@@ -573,7 +573,7 @@ func (r *Session) PushImageLayerRegistry(imgID string, layer io.Reader, registry

 	h.Write([]byte{'\n'})

 	checksumLayer := io.TeeReader(tarsumLayer, h)

-	req, err := http.NewRequest("PUT", u, checksumLayer)

+	req, err := http.NewRequest(http.MethodPut, u, checksumLayer)

 	if err != nil {

 		return "", "", err

 	}

@@ -610,7 +610,7 @@ func (r *Session) PushRegistryTag(remote reference.Named, revision, tag, registr

 	revision = "\"" + revision + "\""

 	path := fmt.Sprintf("repositories/%s/tags/%s", reference.Path(remote), tag)

-	req, err := http.NewRequest("PUT", registry+path, strings.NewReader(revision))

+	req, err := http.NewRequest(http.MethodPut, registry+path, strings.NewReader(revision))

 	if err != nil {

 		return err

 	}

@@ -714,7 +714,7 @@ func (r *Session) PushImageJSONIndex(remote reference.Named, imgList []*ImgData,

 }

 func (r *Session) putImageRequest(u string, headers map[string][]string, body []byte) (*http.Response, error) {

-	req, err := http.NewRequest("PUT", u, bytes.NewReader(body))

+	req, err := http.NewRequest(http.MethodPut, u, bytes.NewReader(body))

 	if err != nil {

 		return nil, err

 	}

@@ -741,7 +741,7 @@ func (r *Session) SearchRepositories(term string, limit int) (*registrytypes.Sea

 	logrus.Debugf("Index server: %s", r.indexEndpoint)

 	u := r.indexEndpoint.String() + "search?q=" + url.QueryEscape(term) + "&n=" + url.QueryEscape(fmt.Sprintf("%d", limit))

-	req, err := http.NewRequest("GET", u, nil)

+	req, err := http.NewRequest(http.MethodGet, u, nil)

 	if err != nil {

 		return nil, errors.Wrap(errdefs.InvalidParameter(err), "Error building request")

 	}