{
			req: &http.Request{
				Header: http.Header{
					"Authorization": []string{"invalid-token"},
				},
			},
			expectedErr: errAuthentication,
		},
	}

	for i, testCase := range testCases {
		_, _, _, gotErr := metricsRequestAuthenticate(testCase.req)
		if testCase.expectedErr != gotErr {
			t.Errorf("Test %d, expected err %s, got %s", i+1, testCase.expectedErr, gotErr)
		}
	}
}