def test_transformer_provides_default_transformer_fn(serve, mod, json_format):
    grpc_proxy_client = Mock()

    def _request(data):
        return data * 2

    grpc_proxy_client.request.side_effect = _request

    transformer = serve.Transformer(grpc_proxy_client=grpc_proxy_client)
    result = transformer.transform("[1,2,3]", "application/json", "application/json")

    assert result == ('[1, 2, 3, 1, 2, 3]', 'application/json')
def test_transformer_default_input_fn_unsupported_type():
    content_type = 'fake/content-type'

    with pytest.raises(UnsupportedContentTypeError):
        serve.Transformer(None)._default_input_fn(None, content_type)