Nil request body with retry

healthcheck/healthcheck.go

@@ -71,7 +71,7 @@ func (b *BackendConfig) newRequest(serverURL *url.URL) (*http.Request, error) {
 
 	u.Path += b.Path
 
-	return http.NewRequest(http.MethodGet, u.String(), nil)
+	return http.NewRequest(http.MethodGet, u.String(), http.NoBody)
 }
 
 // this function adds additional http headers and hostname to http.request

middlewares/auth/forward.go

@@ -40,7 +40,7 @@ func Forward(config *types.Forward, w http.ResponseWriter, r *http.Request, next
 		}
 	}
 
-	forwardReq, err := http.NewRequest(http.MethodGet, config.Address, nil)
+	forwardReq, err := http.NewRequest(http.MethodGet, config.Address, http.NoBody)
 	tracing.LogRequest(tracing.GetSpan(r), forwardReq)
 	if err != nil {
 		tracing.SetErrorAndDebugLog(r, "Error calling %s. Cause %s", config.Address, err)

middlewares/errorpages/error_pages.go

@@ -120,7 +120,7 @@ func newRequest(baseURL string) (*http.Request, error) {
 		return nil, fmt.Errorf("error pages: error when parse URL: %v", err)
 	}
 
-	req, err := http.NewRequest(http.MethodGet, u.String(), nil)
+	req, err := http.NewRequest(http.MethodGet, u.String(), http.NoBody)
 	if err != nil {
 		return nil, fmt.Errorf("error pages: error when create query: %v", err)
 	}

middlewares/retry.go

@@ -35,6 +35,9 @@ func (retry *Retry) ServeHTTP(rw http.ResponseWriter, r *http.Request) {
 	// cf https://github.com/containous/traefik/issues/1008
 	if retry.attempts > 1 {
 		body := r.Body
+		if body == nil {
+			body = http.NoBody
+		}
 		defer body.Close()
 		r.Body = ioutil.NopCloser(body)
 	}