graphene-django/graphene_django/utils.py
2018-07-19 16:52:24 -07:00

84 lines
2.1 KiB
Python

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 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