adminRouter.Methods(http.MethodDelete).Path(adminVersion + "/tier/{tier}").HandlerFunc(adminMiddleware(adminAPI.RemoveTierHandler))
		adminRouter.Methods(http.MethodGet).Path(adminVersion + "/tier/{tier}").HandlerFunc(adminMiddleware(adminAPI.VerifyTierHandler))
		// Tier stats

// high memory usage!
func s3APIMiddleware(f http.HandlerFunc, flags ...s3HFlag) http.HandlerFunc {
	// Collect all flags with bitwise-OR and assign operator
	var handlerFlags s3HFlag
	for _, flag := range flags {
		handlerFlags |= flag
	}

	// Get name of the handler using reflection.
	handlerName := getHandlerName(f, "objectAPIHandlers")

	var handler http.HandlerFunc = func(w http.ResponseWriter, r *http.Request) {

			subrouter.Methods(http.MethodPost).Path(storageRESTVersionPrefix + storageRESTMethodVerifyFile).HandlerFunc(h(server.VerifyFileHandler))
			subrouter.Methods(http.MethodPost).Path(storageRESTVersionPrefix + storageRESTMethodStatInfoFile).HandlerFunc(h(server.StatInfoFile))

		}
	}
	return false
}

// Limits body and header to specific allowed maximum limits as per S3/MinIO API requirements.
func setRequestLimitMiddleware(h http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		tc, ok := r.Context().Value(mcontext.ContextTraceKey).(*mcontext.TraceCtxt)

		// Reject unsupported reserved metadata first before validation.

		if enc != streamingContentEncoding {
			newEncs = append(newEncs, enc)
		}
	}
	return strings.Join(newEncs, ",")
}

func collectInternodeStats(f http.HandlerFunc) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		f.ServeHTTP(w, r)

		tc, ok := r.Context().Value(mcontext.ContextTraceKey).(*mcontext.TraceCtxt)
		if !ok || tc == nil {
			return
		}

	httpServer1 := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {}))
	defer httpServer1.Close()
	httpServer2 := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		fmt.Fprintln(w, "fbe246edbd382902db9a4035df7dce8cb441357d minio.RELEASE.2016-10-07T01-16-39Z")
	}))
	defer httpServer2.Close()
	httpServer3 := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

		noQueries := len(r.URL.RawQuery) == 0
		return ctypeOk && noQueries
	}).HandlerFunc(httpTraceAll(sts.AssumeRoleWithSSO))

	// AssumeRoleWithClientGrants
	stsRouter.Methods(http.MethodPost).HandlerFunc(httpTraceAll(sts.AssumeRoleWithClientGrants)).
		Queries(stsAction, clientGrants).
		Queries(stsVersion, stsAPIVersion).
		Queries(stsToken, "{Token:.*}")

	t.mu.RLock()
	defer t.mu.RUnlock()

	if t.requestsPool == nil {
		return nil
	}

	return t.requestsPool
}

// maxClients throttles the S3 API calls
func maxClients(f http.HandlerFunc) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		globalHTTPStats.incS3RequestsIncoming()

		if r.Header.Get(globalObjectPerfUserMetadata) == "" {
			if val := globalServiceFreeze.Load(); val != nil {

	logger.CriticalIf(GlobalContext, registry.Register(newMinioCollector()))

	gatherers := prometheus.Gatherers{
		prometheus.DefaultGatherer,
		registry,
	}

	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		tc, ok := r.Context().Value(mcontext.ContextTraceKey).(*mcontext.TraceCtxt)
		if ok {
			tc.FuncName = "handler.MetricsLegacy"
			tc.ResponseRecorder.LogErrBody = true

}

// setAuthMiddleware to validate authorization header for the incoming request.
func setAuthMiddleware(h http.Handler) http.Handler {
	// handler for validating incoming authorization headers.
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		tc, ok := r.Context().Value(mcontext.ContextTraceKey).(*mcontext.TraceCtxt)

		aType := getRequestAuthType(r)
		switch aType {