fix ModelPermissionsField representation

rest_framework_fine_permissions/fields.py

@@ -5,9 +5,11 @@
 
 import logging
 import six
+import collections
+
+from django.db import models
 from rest_framework import serializers
-from rest_framework.fields import is_simple_callable
-from rest_framework.fields import Field
+from rest_framework.fields import Field, empty
 
 
 logger = logging.getLogger(__name__)
@@ -16,7 +18,7 @@
 
 
 def get_application(app_label):
-    """ Get application. """
+    """ Get an application. """
     try:
         # django >= 1.7
         from django.apps import apps as django_apps
@@ -29,7 +31,6 @@ def get_application(app_label):
             APP_NAMES = {
                 app.rsplit('.', 1)[-1]: app for app in settings.INSTALLED_APPS
             }
-
         return APP_NAMES[app_label]
 
 
@@ -49,34 +50,30 @@ def get_serializer(serializer):
     return serializer
 
 
-
-
 class ModelPermissionsField(Field):
-    """
-    """
 
-    def __init__(self, serializer, field='', **kwargs):
+    """ Field that acts as a ModelPermissionsSerializer for relations. """
+
+    def __init__(self, serializer, read_only=False, write_only=False,
+                 required=None, default=empty, initial=empty, source=None,
+                 label=None, help_text=None, style=None,
+                 error_messages=None, validators=None, allow_null=False):
         self.serializer = get_serializer(serializer)
         assert self.serializer is not None \
             and issubclass(self.serializer, serializers.ModelSerializer), (
                 "Bad serializer defined %s" % serializer
             )
-        self.field = field
-        super(ModelPermissionsField, self).__init__(**kwargs)
-
-    def _get_serializer(self, attr):
-        many = hasattr(attr, '__iter__') and not isinstance(attr, dict)
-        return self.serializer(attr, context=self.context, many=many)
+        super(ModelPermissionsField, self).__init__(read_only, write_only,
+                                                    required, default, initial,
+                                                    source, label, help_text,
+                                                    style, error_messages,
+                                                    validators, allow_null)
 
     def to_representation(self, obj):
-        attr = getattr(obj, self.field or self.field_name, None)
-
-        assert attr is not None, (
-            "Bad configuration for field %s, "
-            "model %s doesn't have a field with this name" %
-            (self.field_name, self.parent.Meta.model.__name__))
-
-        if is_simple_callable(getattr(attr, 'all', None)):
-            attr = attr.all()
+        """ Represent data for the field. """
+        many = isinstance(obj, collections.Iterable) \
+            or isinstance(obj, models.Manager) \
+            and not isinstance(obj, dict)
 
-        return self._get_serializer(attr).data
+        ser = self.serializer(obj, context=self.context, many=many)
+        return ser.data

rest_framework_fine_permissions/serializers.py

@@ -15,7 +15,6 @@
 from rest_framework.utils.field_mapping import get_relation_kwargs
 
 from .models import FieldPermission
-from .fields import ModelPermissionsField
 
 
 class ModelPermissionsSerializer(serializers.ModelSerializer):
@@ -76,9 +75,6 @@ def get_fields(self):
                         kwargs.pop('view_name', None)
                     field = field_cls(**kwargs)
 
-            if isinstance(field, ModelPermissionsField):
-                field.bind(allowed_field.name, self)
-
             ret[allowed_field.name] = field
         return ret
 

tests/serializers.py

@@ -26,15 +26,15 @@ class Meta:
 class CardSerializer(serializers.ModelPermissionsSerializer):
 
     account = fields.ModelPermissionsField(AccountSerializer)
-    service_names = fields.ModelPermissionsField(ServiceSerializer, field='services')
+    service_names = fields.ModelPermissionsField(ServiceSerializer, source='services')
 
     class Meta:
         model = Card
 
 class AnotherCardSerializer(serializers.ModelPermissionsSerializer):
 
     account = fields.ModelPermissionsField(AccountSerializer)
-    service_names = fields.ModelPermissionsField('tests.ServiceSerializer', field='services')
+    service_names = fields.ModelPermissionsField('tests.ServiceSerializer', source='services')
 
     class Meta:
         model = Card

tests/test_fields.py

@@ -37,27 +37,28 @@ def _add_field_perms(self, app, model, *field_names):
     def _auth_user(self):
         self.request.user = self.user
 
-    def _get_serializer_instance(self, anonymous=False):
+    def _get_serializer_instance(self, instance=None, anonymous=False):
         if anonymous:
-            self.Serializer(context={})
+            self.Serializer(instance=instance, context={})
         self._auth_user()
-        return self.Serializer(context={'request': self.request})
+        return self.Serializer(instance=instance,
+                               context={'request': self.request})
 
     def test_simple_data_in_permissions_field(self):
         """ Test with a many to one field. """
         self._add_field_perms('tests', 'account', 'id', 'user')
         self._add_field_perms('tests', 'card', 'account')
 
-        ser = self._get_serializer_instance()
-        mpf = ser.get_fields()['account']
+        ser = self._get_serializer_instance(instance=self.card)
 
-        representation = mpf.to_representation(self.card)
+        data = ser.data
 
-        self.assertEqual(sorted(representation), ['id', 'user'])
-        self.assertEqual(representation['id'], self.account.id)
+        self.assertEqual(sorted(data['account']), ['id', 'user'])
+        self.assertEqual(data['account']['id'], self.account.id)
 
     def test_list_data_in_permissions_field(self):
         """ Test with a many to one field. """
+        self._add_field_perms('tests', 'account', 'id', 'user')
         self._add_field_perms('tests', 'card', 'id', 'service_names')
         self._add_field_perms('tests', 'service', 'name', 'id')
 
@@ -66,28 +67,12 @@ def test_list_data_in_permissions_field(self):
         self.card.services.add(service)
         self.card.services.add(service2)
 
-        ser = self._get_serializer_instance()
-        mpf = ser.get_fields()['service_names']
-
-        representation = mpf.to_representation(self.card)
-
-        self.assertEqual(sorted(representation[0]), ['id', 'name'])
-        self.assertEqual(len(representation), 2)
-        self.assertEqual(representation[0]['name'], 'chronos')
-
-    def test_bad_configuration(self):
-        """ Test bad instantiation of a model permissions field. """
-        self._add_field_perms('tests', 'card', 'account_name')
-        self.Serializer = serializers.BadCardSerializer
-
-        ser = self._get_serializer_instance()
-        mpf = ser.get_fields()['account_name']
+        ser = self._get_serializer_instance(instance=self.card)
+        data = ser.data
 
-        self.assertRaisesRegexp(
-            AssertionError,
-            "for field account_name, model Card doesn't have a field",
-            mpf.to_representation,
-            self.card)
+        self.assertEqual(sorted(data['service_names'][0]), ['id', 'name'])
+        self.assertEqual(len(data['service_names']), 2)
+        self.assertEqual(data['service_names'][0]['name'], 'chronos')
 
     def test_defined_with_no_dependency(self):
         """ Test with serializer passed as a string. """