Add Django 2 support, bump to v1.0.1

.travis.yml

@@ -9,13 +9,15 @@ python:
   - "3.3"
   - "3.4"
   - "3.5"
+  - "3.6"
 
 # Django versions for matrix
 env:
   - DJANGO_VERSION='>=1.8,<1.9'
   - DJANGO_VERSION='>=1.9,<1.10'
   - DJANGO_VERSION='>=1.10,<1.11'
   - DJANGO_VERSION='>=1.11,<2.0'
+  - DJANGO_VERSION='>=2.0,<2.1'
 
 # Command to install dependencies, e.g. pip install -r requirements.txt --use-mirrors
 install:
@@ -37,6 +39,16 @@ after_success:
 
 matrix:
   exclude:
+    - python: "2.7"
+      env: DJANGO_VERSION='>=2.0,<2.1'
+
+    - python: "3.6"
+      env: DJANGO_VERSION='>=1.8,<1.9'
+    - python: "3.6"
+      env: DJANGO_VERSION='>=1.9,<1.10'
+    - python: "3.6"
+      env: DJANGO_VERSION='>=1.10,<1.11'
+
     - python: "3.5"
       env: DJANGO_VERSION='>=1.8,<1.9'
 
@@ -54,3 +66,8 @@ matrix:
       env: DJANGO_VERSION='>=1.11,<2.0'
     - python: "3.3"
       env: DJANGO_VERSION='>=1.11,<2.0'
+
+    - python: "3.2"
+      env: DJANGO_VERSION='>=2.0,<2.1'
+    - python: "3.3"
+      env: DJANGO_VERSION='>=2.0,<2.1'

compositefk/__init__.py

@@ -2,4 +2,4 @@
 # -*- coding: utf-8 -*-
 
 
-__version__ = "1.0.0a10"
+__version__ = "1.0.1"

compositefk/compat.py

@@ -0,0 +1,29 @@
+import django
+
+
+def get_remote_field(field):
+    if django.VERSION < (1, 9):
+        return field.rel
+    else:
+        return field.remote_field
+
+
+def get_cached_value(instance, descriptor, default=None):
+    if django.VERSION < (2, 0):
+        return getattr(instance, descriptor.cache_name, default)
+    else:
+        return descriptor.field.get_cached_value(instance, default=default)
+
+
+def set_cached_value_by_descriptor(instance, descriptor, value):
+    if django.VERSION < (2, 0):
+        setattr(instance, descriptor.cache_name, value)
+    else:
+        descriptor.field.set_cached_value(instance, value)
+
+
+def set_cached_value_by_field(instance, field, value):
+    if django.VERSION < (2, 0):
+        setattr(instance, field.get_cache_name(), value)
+    else:
+        field.set_cached_value(instance, value)

compositefk/fields.py

@@ -9,12 +9,11 @@
 
 from django.core import checks
 from django.core.exceptions import FieldDoesNotExist
-from django.db.models.expressions import Value
 from django.db.models.fields import Field
 from django.db.models.fields.related import ForeignObject
 from django.db.models.sql.where import WhereNode, AND
-from django.utils import six
 
+from compositefk.compat import get_remote_field
 from compositefk.related_descriptors import CompositeForwardManyToOneDescriptor
 
 try:
@@ -239,8 +238,8 @@ def db_type(self, connection):
     def db_parameters(self, connection):
         return {"type": None, "check": None}
 
-    def contribute_to_class(self, cls, name, virtual_only=False):
-        super(ForeignObject, self).contribute_to_class(cls, name, virtual_only=virtual_only)
+    def contribute_to_class(self, cls, name, **kwargs):
+        super(ForeignObject, self).contribute_to_class(cls, name, **kwargs)
         setattr(cls, self.name, CompositeForwardManyToOneDescriptor(self))
 
     def get_instance_value_for_fields(self, instance, fields):
@@ -275,7 +274,7 @@ class CompositeOneToOneField(CompositeForeignKey):
     def __init__(self, to, **kwargs):
         kwargs['unique'] = True
         super(CompositeOneToOneField, self).__init__(to, **kwargs)
-        self.rel.multiple = False
+        get_remote_field(self).multiple = False
 
     def deconstruct(self):
         name, path, args, kwargs = super(CompositeOneToOneField, self).deconstruct()
@@ -333,6 +332,33 @@ def get_lookup(self, main_field, for_remote, alias):
         return lookup_class(for_remote.get_col(alias), self.value)
 
 
+class FunctionBasedFieldValue(RawFieldValue):
+    def __init__(self, func):
+        self._func = func
+
+    def deconstruct(self):
+        module_name = self.__module__
+        name = self.__class__.__name__
+        return (
+            '%s.%s' % (module_name, name),
+            (self._func,),
+            {}
+        )
+
+    def __eq__(self, other):
+        if self.__class__ != other.__class__:
+            return False
+        return self._func == other._func
+
+    @property
+    def value(self):
+        return self._func()
+
+    @value.setter
+    def value(self):
+        pass
+
+
 class LocalFieldValue(CompositePart):
     """
     implicitly used, represent the value of a local field

compositefk/related_descriptors.py

@@ -5,7 +5,12 @@
 from __future__ import unicode_literals, print_function, absolute_import
 import logging
 
-
+from compositefk.compat import (
+    get_remote_field,
+    set_cached_value_by_descriptor,
+    set_cached_value_by_field,
+    get_cached_value,
+)
 
 try:
     from django.db.models.fields.related_descriptors import ForwardManyToOneDescriptor
@@ -30,30 +35,19 @@ def __set__(self, instance, value):
             # populated the cache, then we don't care - we're only accessing
             # the object to invalidate the accessor cache, so there's no
             # need to populate the cache just to expire it again.
-            related = getattr(instance, self.cache_name, None)
+            related = get_cached_value(instance, self, None)
 
             # If we've got an old related object, we need to clear out its
             # cache. This cache also might not exist if the related object
             # hasn't been accessed yet.
             if related is not None:
-                try:
-                    related_field = self.field.remote_field
-                except AttributeError:
-                    related_field = self.field.rel
-                setattr(related, related_field.get_cache_name(), None)
+                related_field = get_remote_field(self.field)
+                set_cached_value_by_field(related, related_field, None)
 
             # ##### only original part
-
             for lh_field_name, none_value in self.field.nullable_fields.items():
                 setattr(instance, lh_field_name, none_value)
 
-
             # Set the related instance cache used by __get__ to avoid a SQL query
             # when accessing the attribute we just set.
-            setattr(instance, self.cache_name, value)
-
-            # If this is a one-to-one relation, set the reverse accessor cache on
-            # the related object to the current instance to avoid an extra SQL
-            # query if it's accessed later on.
-            if value is not None and not self.field.remote_field.multiple:
-                setattr(value, self.field.remote_field.get_cache_name(), instance)
+            set_cached_value_by_descriptor(instance, self, None)

docs/quickstart.rst

@@ -196,6 +196,60 @@ so the class Supplier could be wrote:
             "type_tiers": RawFieldValue("S")
         })
 
+We also can refer by CompositeForeignKey in more flexible way using FunctionBasedFieldValue instead of RawFieldValue:
+
+.. code:: python
+
+    from django.conf import global_settings
+    from django.utils import translation
+
+
+    class Supplier(models.Model):
+        company = models.IntegerField()
+        supplier_id = models.IntegerField()
+
+
+    class SupplierTranslations(models.Model):
+        master = models.ForeignKey(
+            Supplier,
+            on_delete=CASCADE,
+            related_name='translations',
+            null=True,
+        )
+        language_code = models.CharField(max_length=255, choices=global_settings.LANGUAGES)
+        name = models.CharField(max_length=255)
+        title = models.CharField(max_length=255)
+
+        class Meta:
+            unique_together = ('language_code', 'master')
+
+
+    active_translations = CompositeForeignKey(
+        SupplierTranslations,
+        on_delete=DO_NOTHING,
+        to_fields={
+            'master_id': 'id',
+            'language_code': FunctionBasedFieldValue(translation.get_language)
+        })
+
+
+    active_translations.contribute_to_class(Supplier, 'active_translations')
+
+
+in this example, the Supplier Model joins with SupplierTranslations in current active language and
+supplier_instance.active_translations.name will return different names depend on
+which language was activated by translation.activate(..):
+
+.. code:: python
+
+    translation.activate('en')
+    print Supplier.objects.get(id=1).active_translations.name
+    translation.activate('your_language_code')
+    print Supplier.objects.get(id=1).active_translations.name
+
+output should be:
+ * 'en_language_name'
+ * 'your_language_name'
 
 Treate specific values as None
 ------------------------------

requirements.txt

@@ -1,3 +1,4 @@
-Django<1.9
+Django<2.1
 wheel
-sphinx
+sphinx
+mock

setup.py

@@ -55,6 +55,7 @@
         'Programming Language :: Python :: 3.3',
         'Programming Language :: Python :: 3.4',
         'Programming Language :: Python :: 3.5',
+        'Programming Language :: Python :: 3.6',
         'Operating System :: OS Independent',
         'Topic :: Software Development :: Libraries',
         'Topic :: Utilities',

testapp/fixtures/all_fixtures.json

@@ -135,5 +135,33 @@
       "company": 2,
       "cod_rep": "DB"
     }
+  },
+  {
+    "model": "testapp.MultiLangSupplier",
+    "pk": 1,
+    "fields": {
+      "company": 1,
+      "supplier_id": 1
+    }
+  },
+  {
+    "model": "testapp.SupplierTranslations",
+    "pk": 1,
+    "fields": {
+      "master": 1,
+      "language_code": "en",
+      "name": "en_name",
+      "title": "en_title"
+    }
+  },
+  {
+    "model": "testapp.SupplierTranslations",
+    "pk": 2,
+    "fields": {
+      "master": 1,
+      "language_code": "ru",
+      "name": "ru_name",
+      "title": "ru_title"
+    }
   }
 ]