import inspect from django.db import models from django.db.models.manager import Manager # from graphene.utils import LazyList class LazyList(object): pass try: import django_filters # noqa DJANGO_FILTER_INSTALLED = True except ImportError: DJANGO_FILTER_INSTALLED = False def get_reverse_fields(model, local_field_names): for name, attr in model.__dict__.items(): # Don't duplicate any local fields if name in local_field_names: continue # Django =>1.9 uses 'rel', django <1.9 uses 'related' related = getattr(attr, 'rel', None) or \ getattr(attr, 'related', None) if isinstance(related, models.ManyToOneRel): yield (name, related) elif isinstance(related, models.ManyToManyRel) and not related.symmetrical: yield (name, related) def maybe_queryset(value): if isinstance(value, Manager): value = value.get_queryset() return value def get_model_fields(model): local_fields = [ (field.name, field) for field in sorted(list(model._meta.fields) + list(model._meta.local_many_to_many)) ] # Make sure we don't duplicate local fields with "reverse" version local_field_names = [field[0] for field in local_fields] reverse_fields = get_reverse_fields(model, local_field_names) all_fields = local_fields + list(reverse_fields) return all_fields def get_related_model(field): if hasattr(field, 'rel'): # Django 1.6, 1.7 return field.rel.to return field.related_model def is_valid_django_model(model): return inspect.isclass(model) and issubclass(model, models.Model) def import_single_dispatch(): try: from functools import singledispatch except ImportError: singledispatch = None if not singledispatch: try: from singledispatch import singledispatch except ImportError: pass if not singledispatch: raise Exception( "It seems your python version does not include " "functools.singledispatch. Please install the 'singledispatch' " "package. More information here: " "https://pypi.python.org/pypi/singledispatch" ) return singledispatch