graphene-django/graphene_django/utils.py
Olivia Rodriguez Valdes e7a4538a3e Merge branch 'permissions-to-fields#3' into permission-to-type#5
# Conflicts:
#	graphene_django/fields.py
2019-03-01 12:48:37 -05:00

141 lines
4.1 KiB
Python

import inspect
from django.core.exceptions import PermissionDenied
from django.db import models
from django.db.models.manager import Manager
# from graphene.utils import LazyList
from graphene.types.resolver import get_default_resolver
from graphene.utils.get_unbound_function import get_unbound_function
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
def has_permissions(viewer, permissions):
"""
Verify that at least one permission is accomplished
:param viewer: Field's viewer
:param permissions: Field permissions
:return: True if viewer has permission. False otherwise.
"""
if not permissions:
return True
return any([viewer.has_perm(perm) for perm in permissions])
def resolve_bound_resolver(resolver, root, info, **args):
"""
Resolve provided resolver
:param resolver: Explicit field resolver
:param root: Schema root
:param info: Schema info
:param args: Schema args
:return: Resolved field
"""
resolver = get_unbound_function(resolver)
return resolver(root, info, **args)
def auth_resolver(parent_resolver, permissions, attname, default_value, raise_exception, root, info, **args):
"""
Middleware resolver to check viewer's permissions
:param parent_resolver: Field resolver
:param permissions: Field permissions
:param attname: Field name
:param default_value: Default value to field if no resolver is provided
:param raise_exception: If True a PermissionDenied is raised
:param root: Schema root
:param info: Schema info
:param args: Schema args
:return: Resolved field. None if the viewer does not have permission to access the field.
"""
# Get viewer from context
if not hasattr(info.context, 'user'):
raise PermissionDenied()
user = info.context.user
if has_permissions(user, permissions):
if parent_resolver:
# A resolver is provided in the class
return resolve_bound_resolver(parent_resolver, root, info, **args)
# Get default resolver
return get_default_resolver()(attname, default_value, root, info, **args)
elif raise_exception:
raise PermissionDenied()
return None