django-restframework serialize relations as dictionaries rather then arrays

It is possible by overriding the list serializers and setting list_serializer_class for each serializer that requires it, as I suggested in this answer.

Of course, you will need to adapt it slightly:

class <YourClass>ListSerializer(serializers.ListSerializer):    def to_representation(self, data):        r = super().to_representation(data)        return { item['<key_field>']: item for item in r }

@Michael Rigonis answer (https://stackoverflow.com/a/45238191/270265) was the key to success. I had to tweak it a little, so I was able to use it for the top level as well.:

class DictSerializer(serializers.ListSerializer):    key = None    def __init__(self, *args, **kwargs):        self.key = kwargs.pop('key', self.key)        super().__init__(*args, **kwargs)    def to_representation(self, data):            r = super().to_representation(data)        return {item[self.key]: item for item in r}    @property    def data(self):        # This is a bit nasty, because the only "Many-Serializer" is a ListSerializer we inherit of it,        # but when converting it to json we call the BaseSerializer directly, because we want a Dictionary rather then a list        ret = super(serializers.ListSerializer, self).data        return ReturnDict(ret, serializer=self)