Slumber tries to decode responses before passing them to the serializer, making it unusable for binary formats

[daisylb]

I've been trying to use Slumber with an API that exposes both JSON and MessagePack; it works fine with the former but doesn't work at all when I try to write a custom serialiser for the latter.

It looks like Slumber is trying to decode the response as text in slumber.Resource._try_to_serialize_response; because MessagePack is a binary format, requests.utils.guess_json_utf is returning None, and resp.content.decode(None) works exactly as well as one would expect, so the serialiser doesn't even get called and the consumer code gets returned a raw bytestring.

I'm using Slumber 0.7.1 on Python 3.4.3. The code for my MessagePack serialiser is as follows:

import msgpack
from slumber.serialize import BaseSerializer


class MessagePackSerializer(BaseSerializer):
    key = "msgpack"
    content_types = ("application/msgpack",)

    def loads(self, data):
        return msgpack.loads(data)

    def dumps(self, data):
        return msgpack.dumps(data)

[specialcircumstances]

I've got a similar issue with CBOR. It never calls the dumps function in my serializer.

[specialcircumstances]

This was my fix in slumber.Resource._try_to_serialize_response

        if stype.key == 'cbor':
            return stype.loads(resp.content)

        if type(resp.content) == bytes:

swap cbor for msgpack and it should work I guess