func TestReadonlyHandler(t *testing.T) {
    fixture := func(w http.ResponseWriter, req *http.Request) {
        w.WriteHeader(http.StatusOK)
    }
    hdlrFunc := readonlyHandlerFunc(http.HandlerFunc(fixture))

    tests := []struct {
        method string
        want   int
    }{
        // GET is only passing method
        {"GET", http.StatusOK},

        // everything but GET is StatusNotImplemented
        {"POST", http.StatusNotImplemented},
        {"PUT", http.StatusNotImplemented},
        {"PATCH", http.StatusNotImplemented},
        {"DELETE", http.StatusNotImplemented},
        {"FOO", http.StatusNotImplemented},
    }

    for i, tt := range tests {
        req, _ := http.NewRequest(tt.method, "http://example.com", nil)
        rr := httptest.NewRecorder()
        hdlrFunc(rr, req)

        if tt.want != rr.Code {
            t.Errorf("#%d: incorrect HTTP status code: method=%s want=%d got=%d", i, tt.method, tt.want, rr.Code)
        }
    }
}