The issue is probably this line https://github.com/apache/arrow/blob/8b1c8118b017a941f0102709d72df7e5a9783aa4/cpp/src/arrow/python/python_to_arrow.cc#L504
which uses *PyList_Check* instead of *PyList_CheckExact*. Changing it to the exact form will cause it to use the custom serializer for subclasses of list. On Sun, Mar 4, 2018 at 1:08 AM Mitar <mmi...@gmail.com> wrote: > Hi! > > I have a subclass of numpy and another of pandas which add a metadata > attribute to them. Moreover, I have a subclass of typing.List as a > Python generic with this metadata attribute as well. > > Now, it seems if I serialize this to plasma store and back I get > standard numpy, pandas, or list back, respectively. > > My question is: how can I make it so that proper subclasses are > returned, including the custom metadata attribute? > > I tried to use pyarrow_lib._default_serialization_context.register_type > but it does not seem to work. Moreover, I still worry that even if I > create a serialization for a custom class, if anyone makes a subclass > and tries to store it plasma store they will get back the custom class > and not a subclass. > > This is how I am testing: > > > https://gitlab.com/datadrivendiscovery/metadata/blob/plasma/tests/test_plasma.py#L50 > > And here is the code for custom numpy class and attempt at registering > custom serialization: > > > https://gitlab.com/datadrivendiscovery/metadata/blob/plasma/d3m_metadata/container/numpy.py#L135 > > It looks like custom serialization is not called. > > > Mitar > > -- > http://mitar.tnode.com/ > https://twitter.com/mitar_m >
