Merge branch 'master' of github.com:tomchristie/django-rest-framework

21 files changed, 233 insertions, 102 deletions

diff --git a/rest_framework/authtoken/views.py b/rest_framework/authtoken/views.py
index 103abb27..b75c2e25 100644
--- a/rest_framework/authtoken/views.py
+++ b/rest_framework/authtoken/views.py
@@ -1,5 +1,4 @@
 from rest_framework.views import APIView
-from rest_framework import status
 from rest_framework import parsers
 from rest_framework import renderers
 from rest_framework.response import Response
@@ -12,16 +11,13 @@ class ObtainAuthToken(APIView):
     permission_classes = ()
     parser_classes = (parsers.FormParser, parsers.MultiPartParser, parsers.JSONParser,)
     renderer_classes = (renderers.JSONRenderer,)
-    serializer_class = AuthTokenSerializer
-    model = Token
 
     def post(self, request):
-        serializer = self.serializer_class(data=request.data)
-        if serializer.is_valid():
-            user = serializer.validated_data['user']
-            token, created = Token.objects.get_or_create(user=user)
-            return Response({'token': token.key})
-        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
+        serializer = AuthTokenSerializer(data=request.data)
+        serializer.is_valid(raise_exception=True)
+        user = serializer.validated_data['user']
+        token, created = Token.objects.get_or_create(user=user)
+        return Response({'token': token.key})
 
 
 obtain_auth_token = ObtainAuthToken.as_view()
diff --git a/rest_framework/decorators.py b/rest_framework/decorators.py
index d28d6e22..325435b3 100644
--- a/rest_framework/decorators.py
+++ b/rest_framework/decorators.py
@@ -12,12 +12,14 @@ from rest_framework.views import APIView
 import types
 
 
-def api_view(http_method_names):
+def api_view(http_method_names=None):
 
     """
     Decorator that converts a function-based view into an APIView subclass.
     Takes a list of allowed methods for the view as an argument.
     """
+    if http_method_names is None:
+        http_method_names = ['GET']
 
     def decorator(func):
 
diff --git a/rest_framework/exceptions.py b/rest_framework/exceptions.py
index 0b06d6e6..906de3b0 100644
--- a/rest_framework/exceptions.py
+++ b/rest_framework/exceptions.py
@@ -5,20 +5,44 @@ In addition Django's built in 403 and 404 exceptions are handled.
 (`django.http.Http404` and `django.core.exceptions.PermissionDenied`)
 """
 from __future__ import unicode_literals
+
+from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import ungettext_lazy
 from rest_framework import status
+from rest_framework.compat import force_text
 import math
 
 
+def _force_text_recursive(data):
+    """
+    Descend into a nested data structure, forcing any
+    lazy translation strings into plain text.
+    """
+    if isinstance(data, list):
+        return [
+            _force_text_recursive(item) for item in data
+        ]
+    elif isinstance(data, dict):
+        return dict([
+            (key, _force_text_recursive(value))
+            for key, value in data.items()
+        ])
+    return force_text(data)
+
+
 class APIException(Exception):
     """
     Base class for REST framework exceptions.
     Subclasses should provide `.status_code` and `.default_detail` properties.
     """
     status_code = status.HTTP_500_INTERNAL_SERVER_ERROR
-    default_detail = 'A server error occured'
+    default_detail = _('A server error occured')
 
     def __init__(self, detail=None):
-        self.detail = detail or self.default_detail
+        if detail is not None:
+            self.detail = force_text(detail)
+        else:
+            self.detail = force_text(self.default_detail)
 
     def __str__(self):
         return self.detail
@@ -39,7 +63,7 @@ class ValidationError(APIException):
         # The details should always be coerced to a list if not already.
         if not isinstance(detail, dict) and not isinstance(detail, list):
             detail = [detail]
-        self.detail = detail
+        self.detail = _force_text_recursive(detail)
 
     def __str__(self):
         return str(self.detail)
@@ -47,59 +71,77 @@ class ValidationError(APIException):
 
 class ParseError(APIException):
     status_code = status.HTTP_400_BAD_REQUEST
-    default_detail = 'Malformed request.'
+    default_detail = _('Malformed request.')
 
 
 class AuthenticationFailed(APIException):
     status_code = status.HTTP_401_UNAUTHORIZED
-    default_detail = 'Incorrect authentication credentials.'
+    default_detail = _('Incorrect authentication credentials.')
 
 
 class NotAuthenticated(APIException):
     status_code = status.HTTP_401_UNAUTHORIZED
-    default_detail = 'Authentication credentials were not provided.'
+    default_detail = _('Authentication credentials were not provided.')
 
 
 class PermissionDenied(APIException):
     status_code = status.HTTP_403_FORBIDDEN
-    default_detail = 'You do not have permission to perform this action.'
+    default_detail = _('You do not have permission to perform this action.')
 
 
 class MethodNotAllowed(APIException):
     status_code = status.HTTP_405_METHOD_NOT_ALLOWED
-    default_detail = "Method '%s' not allowed."
+    default_detail = _("Method '%s' not allowed.")
 
     def __init__(self, method, detail=None):
-        self.detail = detail or (self.default_detail % method)
+        if detail is not None:
+            self.detail = force_text(detail)
+        else:
+            self.detail = force_text(self.default_detail) % method
 
 
 class NotAcceptable(APIException):
     status_code = status.HTTP_406_NOT_ACCEPTABLE
-    default_detail = "Could not satisfy the request Accept header"
+    default_detail = _('Could not satisfy the request Accept header')
 
     def __init__(self, detail=None, available_renderers=None):
-        self.detail = detail or self.default_detail
+        if detail is not None:
+            self.detail = force_text(detail)
+        else:
+            self.detail = force_text(self.default_detail)
         self.available_renderers = available_renderers
 
 
 class UnsupportedMediaType(APIException):
     status_code = status.HTTP_415_UNSUPPORTED_MEDIA_TYPE
-    default_detail = "Unsupported media type '%s' in request."
+    default_detail = _("Unsupported media type '%s' in request.")
 
     def __init__(self, media_type, detail=None):
-        self.detail = detail or (self.default_detail % media_type)
+        if detail is not None:
+            self.detail = force_text(detail)
+        else:
+            self.detail = force_text(self.default_detail) % media_type
 
 
 class Throttled(APIException):
     status_code = status.HTTP_429_TOO_MANY_REQUESTS
-    default_detail = 'Request was throttled.'
-    extra_detail = " Expected available in %d second%s."
+    default_detail = _('Request was throttled.')
+    extra_detail = ungettext_lazy(
+        'Expected available in %(wait)d second.',
+        'Expected available in %(wait)d seconds.',
+        'wait'
+    )
 
     def __init__(self, wait=None, detail=None):
+        if detail is not None:
+            self.detail = force_text(detail)
+        else:
+            self.detail = force_text(self.default_detail)
+
         if wait is None:
-            self.detail = detail or self.default_detail
             self.wait = None
         else:
-            format = (detail or self.default_detail) + self.extra_detail
-            self.detail = format % (wait, wait != 1 and 's' or '')
             self.wait = math.ceil(wait)
+            self.detail += ' ' + force_text(
+                self.extra_detail % {'wait': self.wait}
+            )
diff --git a/rest_framework/fields.py b/rest_framework/fields.py
index 36afe7a9..ca9c479f 100644
--- a/rest_framework/fields.py
+++ b/rest_framework/fields.py
@@ -68,8 +68,8 @@ def get_attribute(instance, attrs):
                 return instance[attr]
             except (KeyError, TypeError, AttributeError):
                 raise exc
-    if is_simple_callable(instance):
-        return instance()
+        if is_simple_callable(instance):
+            instance = instance()
     return instance
 
 
@@ -181,6 +181,9 @@ class Field(object):
         self.style = {} if style is None else style
         self.allow_null = allow_null
 
+        if allow_null and self.default_empty_html is empty:
+            self.default_empty_html = None
+
         if validators is not None:
             self.validators = validators[:]
 
@@ -259,7 +262,11 @@ class Field(object):
         if html.is_html_input(dictionary):
             # HTML forms will represent empty fields as '', and cannot
             # represent None or False values directly.
-            ret = dictionary.get(self.field_name, '')
+            if self.field_name not in dictionary:
+                if getattr(self.root, 'partial', False):
+                    return empty
+                return self.default_empty_html
+            ret = dictionary[self.field_name]
             return self.default_empty_html if (ret == '') else ret
         return dictionary.get(self.field_name, empty)
 
@@ -314,7 +321,6 @@ class Field(object):
 
         value = self.to_internal_value(data)
         self.run_validators(value)
-        self.validate(value)
         return value
 
     def run_validators(self, value):
@@ -341,9 +347,6 @@ class Field(object):
         if errors:
             raise ValidationError(errors)
 
-    def validate(self, value):
-        pass
-
     def to_internal_value(self, data):
         """
         Transform the *incoming* primitive data into a native value.
@@ -495,6 +498,7 @@ class CharField(Field):
     }
     initial = ''
     coerce_blank_to_null = False
+    default_empty_html = ''
 
     def __init__(self, **kwargs):
         self.allow_blank = kwargs.pop('allow_blank', False)
@@ -947,6 +951,8 @@ class ChoiceField(Field):
             self.fail('invalid_choice', input=data)
 
     def to_representation(self, value):
+        if value in ('', None):
+            return value
         return self.choice_strings_to_values[six.text_type(value)]
 
 
diff --git a/rest_framework/metadata.py b/rest_framework/metadata.py
index 90d3f2e0..de829d00 100644
--- a/rest_framework/metadata.py
+++ b/rest_framework/metadata.py
@@ -121,7 +121,10 @@ class SimpleMetadata(BaseMetadata):
 
         if hasattr(field, 'choices'):
             field_info['choices'] = [
-                {'value': choice_value, 'display_name': choice_name}
+                {
+                    'value': choice_value,
+                    'display_name': force_text(choice_name, strings_only=True)
+                }
                 for choice_value, choice_name in field.choices.items()
             ]
 
diff --git a/rest_framework/relations.py b/rest_framework/relations.py
index 79c8057b..d1ea497a 100644
--- a/rest_framework/relations.py
+++ b/rest_framework/relations.py
@@ -49,6 +49,21 @@ class RelatedField(Field):
 
     @classmethod
     def many_init(cls, *args, **kwargs):
+        """
+        This method handles creating a parent `ManyRelatedField` instance
+        when the `many=True` keyword argument is passed.
+
+        Typically you won't need to override this method.
+
+        Note that we're over-cautious in passing most arguments to both parent
+        and child classes in order to try to cover the general case. If you're
+        overriding this method you'll probably want something much simpler, eg:
+
+        @classmethod
+        def many_init(cls, *args, **kwargs):
+            kwargs['child'] = cls()
+            return CustomManyRelatedField(*args, **kwargs)
+        """
         list_kwargs = {'child_relation': cls(*args, **kwargs)}
         for key in kwargs.keys():
             if key in MANY_RELATION_KWARGS:
@@ -306,7 +321,9 @@ class ManyRelatedField(Field):
     The `ManyRelatedField` class is responsible for handling iterating through
     the values and passing each one to the child relationship.
 
-    You shouldn't need to be using this class directly yourself.
+    This class is treated as private API.
+    You shouldn't generally need to be using this class directly yourself,
+    and should instead simply set 'many=True' on the relationship.
     """
     initial = []
     default_empty_html = []
diff --git a/rest_framework/renderers.py b/rest_framework/renderers.py
index 6596fc44..e87d16d0 100644
--- a/rest_framework/renderers.py
+++ b/rest_framework/renderers.py
@@ -429,7 +429,10 @@ class HTMLFormRenderer(BaseRenderer):
             style['base_template'] = self.base_template
         style['renderer'] = self
 
-        if 'template' in style:
+        # This API needs to be finessed and finalized for 3.1
+        if 'template' in renderer_context:
+            template_name = renderer_context['template']
+        elif 'template' in style:
             template_name = style['template']
         else:
             template_name = style['template_pack'].strip('/') + '/' + style['base_template']
@@ -522,7 +525,10 @@ class BrowsableAPIRenderer(BaseRenderer):
         else:
             instance = None
 
-        if request.method == method:
+        # If this is valid serializer data, and the form is for the same
+        # HTTP method as was used in the request then use the existing
+        # serializer instance, rather than dynamically creating a new one.
+        if request.method == method and serializer is not None:
             try:
                 data = request.data
             except ParseError:
@@ -555,7 +561,14 @@ class BrowsableAPIRenderer(BaseRenderer):
                 if data is not None:
                     serializer.is_valid()
             form_renderer = self.form_renderer_class()
-            return form_renderer.render(serializer.data, self.accepted_media_type, self.renderer_context)
+            return form_renderer.render(
+                serializer.data,
+                self.accepted_media_type,
+                dict(
+                    list(self.renderer_context.items()) +
+                    [('template', 'rest_framework/api_form.html')]
+                )
+            )
 
     def get_raw_data_form(self, data, view, method, request):
         """
diff --git a/rest_framework/request.py b/rest_framework/request.py
index 096b3042..d7e74674 100644
--- a/rest_framework/request.py
+++ b/rest_framework/request.py
@@ -310,7 +310,7 @@ class Request(object):
 
     def _load_data_and_files(self):
         """
-        Parses the request content into self.DATA and self.FILES.
+        Parses the request content into `self.data`.
         """
         if not _hasattr(self, '_content_type'):
             self._load_method_and_content_type()
diff --git a/rest_framework/response.py b/rest_framework/response.py
index 0a7d313f..d6ca1aad 100644
--- a/rest_framework/response.py
+++ b/rest_framework/response.py
@@ -5,7 +5,6 @@ it is initialized with unrendered data, instead of a pre-rendered string.
 The appropriate renderer is called during Django's template response rendering.
 """
 from __future__ import unicode_literals
-import django
 from django.core.handlers.wsgi import STATUS_CODE_TEXT
 from django.template.response import SimpleTemplateResponse
 from django.utils import six
@@ -16,9 +15,6 @@ class Response(SimpleTemplateResponse):
     An HttpResponse that allows its data to be rendered into
     arbitrary media types.
     """
-    # TODO: remove that once Django 1.3 isn't supported
-    if django.VERSION >= (1, 4):
-        rendering_attrs = SimpleTemplateResponse.rendering_attrs + ['_closable_objects']
 
     def __init__(self, data=None, status=None,
                  template_name=None, headers=None,
diff --git a/rest_framework/serializers.py b/rest_framework/serializers.py
index 84282cdb..f7aa3a7d 100644
--- a/rest_framework/serializers.py
+++ b/rest_framework/serializers.py
@@ -86,6 +86,15 @@ class BaseSerializer(Field):
         class when `many=True` is used. You can customize it if you need to
         control which keyword arguments are passed to the parent, and
         which are passed to the child.
+
+        Note that we're over-cautious in passing most arguments to both parent
+        and child classes in order to try to cover the general case. If you're
+        overriding this method you'll probably want something much simpler, eg:
+
+        @classmethod
+        def many_init(cls, *args, **kwargs):
+            kwargs['child'] = cls()
+            return CustomListSerializer(*args, **kwargs)
         """
         child_serializer = cls(*args, **kwargs)
         list_kwargs = {'child': child_serializer}
@@ -93,7 +102,9 @@ class BaseSerializer(Field):
             (key, value) for key, value in kwargs.items()
             if key in LIST_SERIALIZER_KWARGS
         ]))
-        return ListSerializer(*args, **list_kwargs)
+        meta = getattr(cls, 'Meta', None)
+        list_serializer_class = getattr(meta, 'list_serializer_class', ListSerializer)
+        return list_serializer_class(*args, **list_kwargs)
 
     def to_internal_value(self, data):
         raise NotImplementedError('`to_internal_value()` must be implemented.')
@@ -362,14 +373,9 @@ class Serializer(BaseSerializer):
         for field in fields:
             attribute = field.get_attribute(instance)
             if attribute is None:
-                value = None
+                ret[field.field_name] = None
             else:
-                value = field.to_representation(attribute)
-            transform_method = getattr(self, 'transform_' + field.field_name, None)
-            if transform_method is not None:
-                value = transform_method(value)
-
-            ret[field.field_name] = value
+                ret[field.field_name] = field.to_representation(attribute)
 
         return ret
 
@@ -720,49 +726,62 @@ class ModelSerializer(Serializer):
         # Determine if we need any additional `HiddenField` or extra keyword
         # arguments to deal with `unique_for` dates that are required to
         # be in the input data in order to validate it.
-        unique_fields = {}
+        hidden_fields = {}
+        unique_constraint_names = set()
+
         for model_field_name, field_name in model_field_mapping.items():
             try:
                 model_field = model._meta.get_field(model_field_name)
             except FieldDoesNotExist:
                 continue
 
-            # Deal with each of the `unique_for_*` cases.
-            for date_field_name in (
+            # Include each of the `unique_for_*` field names.
+            unique_constraint_names |= set([
                 model_field.unique_for_date,
                 model_field.unique_for_month,
                 model_field.unique_for_year
-            ):
-                if date_field_name is None:
-                    continue
-
-                # Get the model field that is refered too.
-                date_field = model._meta.get_field(date_field_name)
-
-                if date_field.auto_now_add:
-                    default = CreateOnlyDefault(timezone.now)
-                elif date_field.auto_now:
-                    default = timezone.now
-                elif date_field.has_default():
-                    default = model_field.default
-                else:
-                    default = empty
-
-                if date_field_name in model_field_mapping:
-                    # The corresponding date field is present in the serializer
-                    if date_field_name not in extra_kwargs:
-                        extra_kwargs[date_field_name] = {}
-                    if default is empty:
-                        if 'required' not in extra_kwargs[date_field_name]:
-                            extra_kwargs[date_field_name]['required'] = True
-                    else:
-                        if 'default' not in extra_kwargs[date_field_name]:
-                            extra_kwargs[date_field_name]['default'] = default
+            ])
+
+        unique_constraint_names -= set([None])
+
+        # Include each of the `unique_together` field names,
+        # so long as all the field names are included on the serializer.
+        for parent_class in [model] + list(model._meta.parents.keys()):
+            for unique_together_list in parent_class._meta.unique_together:
+                if set(fields).issuperset(set(unique_together_list)):
+                    unique_constraint_names |= set(unique_together_list)
+
+        # Now we have all the field names that have uniqueness constraints
+        # applied, we can add the extra 'required=...' or 'default=...'
+        # arguments that are appropriate to these fields, or add a `HiddenField` for it.
+        for unique_constraint_name in unique_constraint_names:
+            # Get the model field that is refered too.
+            unique_constraint_field = model._meta.get_field(unique_constraint_name)
+
+            if getattr(unique_constraint_field, 'auto_now_add', None):
+                default = CreateOnlyDefault(timezone.now)
+            elif getattr(unique_constraint_field, 'auto_now', None):
+                default = timezone.now
+            elif unique_constraint_field.has_default():
+                default = unique_constraint_field.default
+            else:
+                default = empty
+
+            if unique_constraint_name in model_field_mapping:
+                # The corresponding field is present in the serializer
+                if unique_constraint_name not in extra_kwargs:
+                    extra_kwargs[unique_constraint_name] = {}
+                if default is empty:
+                    if 'required' not in extra_kwargs[unique_constraint_name]:
+                        extra_kwargs[unique_constraint_name]['required'] = True
                 else:
-                    # The corresponding date field is not present in the,
-                    # serializer. We have a default to use for the date, so
-                    # add in a hidden field that populates it.
-                    unique_fields[date_field_name] = HiddenField(default=default)
+                    if 'default' not in extra_kwargs[unique_constraint_name]:
+                        extra_kwargs[unique_constraint_name]['default'] = default
+            elif default is not empty:
+                # The corresponding field is not present in the,
+                # serializer. We have a default to use for it, so
+                # add in a hidden field that populates it.
+                hidden_fields[unique_constraint_name] = HiddenField(default=default)
 
         # Now determine the fields that should be included on the serializer.
         for field_name in fields:
@@ -838,12 +857,16 @@ class ModelSerializer(Serializer):
                     'validators', 'queryset'
                 ]:
                     kwargs.pop(attr, None)
+
+            if extras.get('default') and kwargs.get('required') is False:
+                kwargs.pop('required')
+
             kwargs.update(extras)
 
             # Create the serializer field.
             ret[field_name] = field_cls(**kwargs)
 
-        for field_name, field in unique_fields.items():
+        for field_name, field in hidden_fields.items():
             ret[field_name] = field
 
         return ret
diff --git a/rest_framework/templates/rest_framework/api_form.html b/rest_framework/templates/rest_framework/api_form.html
new file mode 100644
index 00000000..96f924ed
--- /dev/null
+++ b/rest_framework/templates/rest_framework/api_form.html
@@ -0,0 +1,8 @@
+{% load rest_framework %}
+{% csrf_token %}
+{% for field in form %}
+    {% if not field.read_only %}
+        {% render_field field style=style %}
+    {% endif %}
+{% endfor %}
+<!-- form.non_field_errors -->
diff --git a/rest_framework/templates/rest_framework/base.html b/rest_framework/templates/rest_framework/base.html
index e9d99a65..e9668193 100644
--- a/rest_framework/templates/rest_framework/base.html
+++ b/rest_framework/templates/rest_framework/base.html
@@ -237,13 +237,6 @@
             </div>
             <!-- END Content -->
             </div><!-- /.container -->
-
-            <footer>
-                {% block footer %}
-                    <p>Sponsored by <a href="http://dabapps.com/">DabApps</a>.</p>
-                {% endblock %}
-            </footer>
-
         </div><!-- ./wrapper -->
 
         {% block script %}
diff --git a/rest_framework/templates/rest_framework/horizontal/list_fieldset.html b/rest_framework/templates/rest_framework/horizontal/list_fieldset.html
index a30514c6..a9ff04a6 100644
--- a/rest_framework/templates/rest_framework/horizontal/list_fieldset.html
+++ b/rest_framework/templates/rest_framework/horizontal/list_fieldset.html
@@ -5,9 +5,12 @@
             <legend class="control-label col-sm-2 {% if style.hide_label %}sr-only{% endif %}" style="border-bottom: 0">{{ field.label }}</legend>
         </div>
     {% endif %}
+    <!--
     <ul>
     {% for child in field.value %}
         <li>TODO</li>
     {% endfor %}
     </ul>
+    -->
+    <p>Lists are not currently supported in HTML input.</p>
 </fieldset>
diff --git a/rest_framework/templates/rest_framework/horizontal/select.html b/rest_framework/templates/rest_framework/horizontal/select.html
index 1d00f424..380b38e9 100644
--- a/rest_framework/templates/rest_framework/horizontal/select.html
+++ b/rest_framework/templates/rest_framework/horizontal/select.html
@@ -4,6 +4,9 @@
     {% endif %}
     <div class="col-sm-10">
         <select class="form-control" name="{{ field.name }}">
+        {% if field.allow_null %}
+            <option value="" {% if not field.value %}selected{% endif %}>--------</option>
+        {% endif %}
         {% for key, text in field.choices.items %}
             <option value="{{ key }}" {% if key == field.value %}selected{% endif %}>{{ text }}</option>
         {% endfor %}
diff --git a/rest_framework/templates/rest_framework/inline/list_fieldset.html b/rest_framework/templates/rest_framework/inline/list_fieldset.html
new file mode 100644
index 00000000..2ae56d7c
--- /dev/null
+++ b/rest_framework/templates/rest_framework/inline/list_fieldset.html
@@ -0,0 +1 @@
+<span>Lists are not currently supported in HTML input.</span>
diff --git a/rest_framework/templates/rest_framework/inline/select.html b/rest_framework/templates/rest_framework/inline/select.html
index e9fcebb4..53af2772 100644
--- a/rest_framework/templates/rest_framework/inline/select.html
+++ b/rest_framework/templates/rest_framework/inline/select.html
@@ -3,8 +3,11 @@
         <label class="sr-only">{{ field.label }}</label>
     {% endif %}
     <select class="form-control" name="{{ field.name }}">
+        {% if field.allow_null %}
+            <option value="" {% if not field.value %}selected{% endif %}>--------</option>
+        {% endif %}
         {% for key, text in field.choices.items %}
-        <option value="{{ key }}" {% if key == field.value %}selected{% endif %}>{{ text }}</option>
+            <option value="{{ key }}" {% if key == field.value %}selected{% endif %}>{{ text }}</option>
         {% endfor %}
     </select>
 </div>
diff --git a/rest_framework/templates/rest_framework/login_base.html b/rest_framework/templates/rest_framework/login_base.html
index 8ab682ac..e050cbdc 100644
--- a/rest_framework/templates/rest_framework/login_base.html
+++ b/rest_framework/templates/rest_framework/login_base.html
@@ -22,7 +22,7 @@
                                 <div id="div_id_username"
                                     class="clearfix control-group {% if form.username.errors %}error{% endif %}">
                                     <div class="controls">
-                                        <Label class="span4">Username:</label>
+                                        <label class="span4">Username:</label>
                                         <input style="height: 25px" type="text" name="username" maxlength="100"
                                             autocapitalize="off"
                                             autocorrect="off" class="span12 textinput textInput"
@@ -36,9 +36,10 @@
                                     </div>
                                 </div>
                                     <div id="div_id_password"
-                                        class="clearfix control-group {% if form.password.errors %}error{% endif %}">
+                                        class="clearfix control-group {% if form.password.errors %}error{% endif %}"
+                                        style="margin-top: 10px">
                                         <div class="controls">
-                                        <Label class="span4">Password:</label>
+                                        <label class="span4">Password:</label>
                                         <input style="height: 25px" type="password" name="password" maxlength="100"
                                             autocapitalize="off" autocorrect="off" class="span12 textinput textInput"
                                             id="id_password" required>
@@ -55,7 +56,7 @@
                                         <div class="well well-small text-error" style="border: none">{{ error }}</div>
                                     {% endfor %}
                                 {% endif %}
-                                <div class="form-actions-no-box">
+                                <div class="form-actions-no-box" style="margin-top: 20px">
                                     <input type="submit" name="submit" value="Log in" class="btn btn-primary" id="submit-id-submit">
                                 </div>
                             </form>
diff --git a/rest_framework/templates/rest_framework/vertical/list_fieldset.html b/rest_framework/templates/rest_framework/vertical/list_fieldset.html
index 74bbf448..1d86c7f2 100644
--- a/rest_framework/templates/rest_framework/vertical/list_fieldset.html
+++ b/rest_framework/templates/rest_framework/vertical/list_fieldset.html
@@ -4,4 +4,5 @@
     {% for field_item in field.value.field_items.values() %}
         {{ renderer.render_field(field_item, layout=layout) }}
     {% endfor %} -->
+    <p>Lists are not currently supported in HTML input.</p>
 </fieldset>
diff --git a/rest_framework/templates/rest_framework/vertical/select.html b/rest_framework/templates/rest_framework/vertical/select.html
index 7c673ebb..de72e1dd 100644
--- a/rest_framework/templates/rest_framework/vertical/select.html
+++ b/rest_framework/templates/rest_framework/vertical/select.html
@@ -3,8 +3,11 @@
         <label {% if style.hide_label %}class="sr-only"{% endif %}>{{ field.label }}</label>
     {% endif %}
     <select class="form-control" name="{{ field.name }}">
+        {% if field.allow_null %}
+            <option value="" {% if not field.value %}selected{% endif %}>--------</option>
+        {% endif %}
         {% for key, text in field.choices.items %}
-        <option value="{{ key }}" {% if key == field.value %}selected{% endif %}>{{ text }}</option>
+            <option value="{{ key }}" {% if key == field.value %}selected{% endif %}>{{ text }}</option>
         {% endfor %}
     </select>
     {% if field.errors %}
diff --git a/rest_framework/utils/model_meta.py b/rest_framework/utils/model_meta.py
index 82361edf..c98725c6 100644
--- a/rest_framework/utils/model_meta.py
+++ b/rest_framework/utils/model_meta.py
@@ -6,6 +6,7 @@ relationships and their associated metadata.
 Usage: `get_field_info(model)` returns a `FieldInfo` instance.
 """
 from collections import namedtuple
+from django.core.exceptions import ImproperlyConfigured
 from django.db import models
 from django.utils import six
 from rest_framework.compat import OrderedDict
@@ -43,7 +44,11 @@ def _resolve_model(obj):
     """
     if isinstance(obj, six.string_types) and len(obj.split('.')) == 2:
         app_name, model_name = obj.split('.')
-        return models.get_model(app_name, model_name)
+        resolved_model = models.get_model(app_name, model_name)
+        if resolved_model is None:
+            msg = "Django did not return a model for {0}.{1}"
+            raise ImproperlyConfigured(msg.format(app_name, model_name))
+        return resolved_model
     elif inspect.isclass(obj) and issubclass(obj, models.Model):
         return obj
     raise ValueError("{0} is not a Django model".format(obj))
diff --git a/rest_framework/validators.py b/rest_framework/validators.py
index fa4f1847..7ca4e6a9 100644
--- a/rest_framework/validators.py
+++ b/rest_framework/validators.py
@@ -93,6 +93,9 @@ class UniqueTogetherValidator:
         The `UniqueTogetherValidator` always forces an implied 'required'
         state on the fields it applies to.
         """
+        if self.instance is not None:
+            return
+
         missing = dict([
             (field_name, self.missing_message)
             for field_name in self.fields
@@ -105,8 +108,17 @@ class UniqueTogetherValidator:
         """
         Filter the queryset to all instances matching the given attributes.
         """
+        # If this is an update, then any unprovided field should
+        # have it's value set based on the existing instance attribute.
+        if self.instance is not None:
+            for field_name in self.fields:
+                if field_name not in attrs:
+                    attrs[field_name] = getattr(self.instance, field_name)
+
+        # Determine the filter keyword arguments and filter the queryset.
         filter_kwargs = dict([
-            (field_name, attrs[field_name]) for field_name in self.fields
+            (field_name, attrs[field_name])
+            for field_name in self.fields
         ])
         return queryset.filter(**filter_kwargs)