1 files changed, 111 insertions, 0 deletions
diff --git a/rest_framework/relations.py b/rest_framework/relations.py
index e69de29b..42d2c121 100644
--- a/rest_framework/relations.py
+++ b/rest_framework/relations.py
@@ -0,0 +1,111 @@
+from rest_framework.fields import Field
+from django.core.exceptions import ObjectDoesNotExist
+from django.core.urlresolvers import resolve, get_script_prefix
+from rest_framework.compat import urlparse
+
+
+def get_default_queryset(serializer_class, field_name):
+    manager = getattr(serializer_class.opts.model, field_name)
+    if hasattr(manager, 'related'):
+        # Forward relationships
+        return manager.related.model._default_manager.all()
+    # Reverse relationships
+    return manager.field.rel.to._default_manager.all()
+
+
+class RelatedField(Field):
+    def __init__(self, **kwargs):
+        self.queryset = kwargs.pop('queryset', None)
+        self.many = kwargs.pop('many', False)
+        super(RelatedField, self).__init__(**kwargs)
+
+    def bind(self, field_name, parent, root):
+        super(RelatedField, self).bind(field_name, parent, root)
+        if self.queryset is None and not self.read_only:
+            self.queryset = get_default_queryset(parent, self.source)
+
+
+class PrimaryKeyRelatedField(RelatedField):
+    MESSAGES = {
+        'required': 'This field is required.',
+        'does_not_exist': "Invalid pk '{pk_value}' - object does not exist.",
+        'incorrect_type': 'Incorrect type.  Expected pk value, received {data_type}.',
+    }
+
+    def from_native(self, data):
+        try:
+            return self.queryset.get(pk=data)
+        except ObjectDoesNotExist:
+            self.fail('does_not_exist', pk_value=data)
+        except (TypeError, ValueError):
+            self.fail('incorrect_type', data_type=type(data).__name__)
+
+
+class HyperlinkedRelatedField(RelatedField):
+    lookup_field = 'pk'
+
+    MESSAGES = {
+        'required': 'This field is required.',
+        'no_match': 'Invalid hyperlink - No URL match',
+        'incorrect_match': 'Invalid hyperlink - Incorrect URL match.',
+        'does_not_exist': "Invalid hyperlink - Object does not exist.",
+        'incorrect_type': 'Incorrect type.  Expected URL string, received {data_type}.',
+    }
+
+    def __init__(self, **kwargs):
+        self.view_name = kwargs.pop('view_name')
+        self.lookup_field = kwargs.pop('lookup_field', self.lookup_field)
+        self.lookup_url_kwarg = kwargs.pop('lookup_url_kwarg', self.lookup_field)
+        super(HyperlinkedRelatedField, self).__init__(**kwargs)
+
+    def get_object(self, view_name, view_args, view_kwargs):
+        """
+        Return the object corresponding to a matched URL.
+
+        Takes the matched URL conf arguments, and should return an
+        object instance, or raise an `ObjectDoesNotExist` exception.
+        """
+        lookup_value = view_kwargs[self.lookup_url_kwarg]
+        lookup_kwargs = {self.lookup_field: lookup_value}
+        return self.queryset.get(**lookup_kwargs)
+
+    def from_native(self, value):
+        try:
+            http_prefix = value.startswith(('http:', 'https:'))
+        except AttributeError:
+            self.fail('incorrect_type', type(value).__name__)
+
+        if http_prefix:
+            # If needed convert absolute URLs to relative path
+            value = urlparse.urlparse(value).path
+            prefix = get_script_prefix()
+            if value.startswith(prefix):
+                value = '/' + value[len(prefix):]
+
+        try:
+            match = resolve(value)
+        except Exception:
+            self.fail('no_match')
+
+        if match.view_name != self.view_name:
+            self.fail('incorrect_match')
+
+        try:
+            return self.get_object(match.view_name, match.args, match.kwargs)
+        except (ObjectDoesNotExist, TypeError, ValueError):
+            self.fail('does_not_exist')
+
+
+class HyperlinkedIdentityField(RelatedField):
+    lookup_field = 'pk'
+
+    def __init__(self, **kwargs):
+        self.view_name = kwargs.pop('view_name')
+        self.lookup_field = kwargs.pop('lookup_field', self.lookup_field)
+        self.lookup_url_kwarg = kwargs.pop('lookup_url_kwarg', self.lookup_field)
+        super(HyperlinkedIdentityField, self).__init__(**kwargs)
+
+
+class SlugRelatedField(RelatedField):
+    def __init__(self, **kwargs):
+        self.slug_field = kwargs.pop('slug_field', None)