6 files changed, 118 insertions, 28 deletions

diff --git a/rest_framework/utils/encoders.py b/rest_framework/utils/encoders.py
index 0bd24939..2160d18b 100644
--- a/rest_framework/utils/encoders.py
+++ b/rest_framework/utils/encoders.py
@@ -6,9 +6,11 @@ from django.db.models.query import QuerySet
 from django.utils import six, timezone
 from django.utils.encoding import force_text
 from django.utils.functional import Promise
+from rest_framework.compat import total_seconds
 import datetime
 import decimal
 import json
+import uuid
 
 
 class JSONEncoder(json.JSONEncoder):
@@ -38,10 +40,12 @@ class JSONEncoder(json.JSONEncoder):
                 representation = representation[:12]
             return representation
         elif isinstance(obj, datetime.timedelta):
-            return six.text_type(obj.total_seconds())
+            return six.text_type(total_seconds(obj))
         elif isinstance(obj, decimal.Decimal):
             # Serializers will coerce decimals to strings by default.
             return float(obj)
+        elif isinstance(obj, uuid.UUID):
+            return six.text_type(obj)
         elif isinstance(obj, QuerySet):
             return tuple(obj)
         elif hasattr(obj, 'tolist'):
diff --git a/rest_framework/utils/field_mapping.py b/rest_framework/utils/field_mapping.py
index fca97b4b..c97ec5d0 100644
--- a/rest_framework/utils/field_mapping.py
+++ b/rest_framework/utils/field_mapping.py
@@ -10,6 +10,11 @@ from rest_framework.validators import UniqueValidator
 import inspect
 
 
+NUMERIC_FIELD_TYPES = (
+    models.IntegerField, models.FloatField, models.DecimalField
+)
+
+
 class ClassLookupDict(object):
     """
     Takes a dictionary with classes as keys.
@@ -33,6 +38,9 @@ class ClassLookupDict(object):
                 return self.mapping[cls]
         raise KeyError('Class %s not found in lookup.', cls.__name__)
 
+    def __setitem__(self, key, value):
+        self.mapping[key] = value
+
 
 def needs_label(model_field, field_name):
     """
@@ -80,7 +88,7 @@ def get_field_kwargs(field_name, model_field):
         kwargs['decimal_places'] = decimal_places
 
     if isinstance(model_field, models.TextField):
-        kwargs['style'] = {'type': 'textarea'}
+        kwargs['style'] = {'base_template': 'textarea.html'}
 
     if isinstance(model_field, models.AutoField) or not model_field.editable:
         # If this field is read-only, then return early.
@@ -106,7 +114,7 @@ def get_field_kwargs(field_name, model_field):
     # Ensure that max_length is passed explicitly as a keyword arg,
     # rather than as a validator.
     max_length = getattr(model_field, 'max_length', None)
-    if max_length is not None:
+    if max_length is not None and isinstance(model_field, models.CharField):
         kwargs['max_length'] = max_length
         validator_kwarg = [
             validator for validator in validator_kwarg
@@ -119,7 +127,7 @@ def get_field_kwargs(field_name, model_field):
         validator.limit_value for validator in validator_kwarg
         if isinstance(validator, validators.MinLengthValidator)
     ), None)
-    if min_length is not None:
+    if min_length is not None and isinstance(model_field, models.CharField):
         kwargs['min_length'] = min_length
         validator_kwarg = [
             validator for validator in validator_kwarg
@@ -132,7 +140,7 @@ def get_field_kwargs(field_name, model_field):
         validator.limit_value for validator in validator_kwarg
         if isinstance(validator, validators.MaxValueValidator)
     ), None)
-    if max_value is not None:
+    if max_value is not None and isinstance(model_field, NUMERIC_FIELD_TYPES):
         kwargs['max_value'] = max_value
         validator_kwarg = [
             validator for validator in validator_kwarg
@@ -145,7 +153,7 @@ def get_field_kwargs(field_name, model_field):
         validator.limit_value for validator in validator_kwarg
         if isinstance(validator, validators.MinValueValidator)
     ), None)
-    if min_value is not None:
+    if min_value is not None and isinstance(model_field, NUMERIC_FIELD_TYPES):
         kwargs['min_value'] = min_value
         validator_kwarg = [
             validator for validator in validator_kwarg
diff --git a/rest_framework/utils/formatting.py b/rest_framework/utils/formatting.py
index 470af51b..8b6f005e 100644
--- a/rest_framework/utils/formatting.py
+++ b/rest_framework/utils/formatting.py
@@ -2,12 +2,10 @@
 Utility functions to return a formatted name and description for a given view.
 """
 from __future__ import unicode_literals
-import re
-
 from django.utils.html import escape
 from django.utils.safestring import mark_safe
-
 from rest_framework.compat import apply_markdown, force_text
+import re
 
 
 def remove_trailing_string(content, trailing):
@@ -59,4 +57,5 @@ def markup_description(description):
         description = apply_markdown(description)
     else:
         description = escape(description).replace('\n', '<br />')
+        description = '<p>' + description + '</p>'
     return mark_safe(description)
diff --git a/rest_framework/utils/model_meta.py b/rest_framework/utils/model_meta.py
index c98725c6..dd92f8b6 100644
--- a/rest_framework/utils/model_meta.py
+++ b/rest_framework/utils/model_meta.py
@@ -24,7 +24,7 @@ FieldInfo = namedtuple('FieldResult', [
 
 RelationInfo = namedtuple('RelationInfo', [
     'model_field',
-    'related',
+    'related_model',
     'to_many',
     'has_through_model'
 ])
@@ -35,7 +35,7 @@ def _resolve_model(obj):
     Resolve supplied `obj` to a Django model class.
 
     `obj` must be a Django model class itself, or a string
-    representation of one.  Useful in situtations like GH #1225 where
+    representation of one.  Useful in situations like GH #1225 where
     Django may not have resolved a string-based reference to a model in
     another model's foreign key definition.
 
@@ -56,28 +56,49 @@ def _resolve_model(obj):
 
 def get_field_info(model):
     """
-    Given a model class, returns a `FieldInfo` instance containing metadata
-    about the various field types on the model.
+    Given a model class, returns a `FieldInfo` instance, which is a
+    `namedtuple`, containing metadata about the various field types on the model
+    including information about their relationships.
     """
     opts = model._meta.concrete_model._meta
 
-    # Deal with the primary key.
+    pk = _get_pk(opts)
+    fields = _get_fields(opts)
+    forward_relations = _get_forward_relationships(opts)
+    reverse_relations = _get_reverse_relationships(opts)
+    fields_and_pk = _merge_fields_and_pk(pk, fields)
+    relationships = _merge_relationships(forward_relations, reverse_relations)
+
+    return FieldInfo(pk, fields, forward_relations, reverse_relations,
+                     fields_and_pk, relationships)
+
+
+def _get_pk(opts):
     pk = opts.pk
     while pk.rel and pk.rel.parent_link:
-        # If model is a child via multitable inheritance, use parent's pk.
+        # If model is a child via multi-table inheritance, use parent's pk.
         pk = pk.rel.to._meta.pk
 
-    # Deal with regular fields.
+    return pk
+
+
+def _get_fields(opts):
     fields = OrderedDict()
     for field in [field for field in opts.fields if field.serialize and not field.rel]:
         fields[field.name] = field
 
-    # Deal with forward relationships.
+    return fields
+
+
+def _get_forward_relationships(opts):
+    """
+    Returns an `OrderedDict` of field names to `RelationInfo`.
+    """
     forward_relations = OrderedDict()
     for field in [field for field in opts.fields if field.serialize and field.rel]:
         forward_relations[field.name] = RelationInfo(
             model_field=field,
-            related=_resolve_model(field.rel.to),
+            related_model=_resolve_model(field.rel.to),
             to_many=False,
             has_through_model=False
         )
@@ -86,20 +107,31 @@ def get_field_info(model):
     for field in [field for field in opts.many_to_many if field.serialize]:
         forward_relations[field.name] = RelationInfo(
             model_field=field,
-            related=_resolve_model(field.rel.to),
+            related_model=_resolve_model(field.rel.to),
             to_many=True,
             has_through_model=(
                 not field.rel.through._meta.auto_created
             )
         )
 
-    # Deal with reverse relationships.
+    return forward_relations
+
+
+def _get_reverse_relationships(opts):
+    """
+    Returns an `OrderedDict` of field names to `RelationInfo`.
+    """
+    # Note that we have a hack here to handle internal API differences for
+    # this internal API across Django 1.7 -> Django 1.8.
+    # See: https://code.djangoproject.com/ticket/24208
+
     reverse_relations = OrderedDict()
     for relation in opts.get_all_related_objects():
         accessor_name = relation.get_accessor_name()
+        related = getattr(relation, 'related_model', relation.model)
         reverse_relations[accessor_name] = RelationInfo(
             model_field=None,
-            related=relation.model,
+            related_model=related,
             to_many=relation.field.rel.multiple,
             has_through_model=False
         )
@@ -107,9 +139,10 @@ def get_field_info(model):
     # Deal with reverse many-to-many relationships.
     for relation in opts.get_all_related_many_to_many_objects():
         accessor_name = relation.get_accessor_name()
+        related = getattr(relation, 'related_model', relation.model)
         reverse_relations[accessor_name] = RelationInfo(
             model_field=None,
-            related=relation.model,
+            related_model=related,
             to_many=True,
             has_through_model=(
                 (getattr(relation.field.rel, 'through', None) is not None)
@@ -117,18 +150,20 @@ def get_field_info(model):
             )
         )
 
-    # Shortcut that merges both regular fields and the pk,
-    # for simplifying regular field lookup.
+    return reverse_relations
+
+
+def _merge_fields_and_pk(pk, fields):
     fields_and_pk = OrderedDict()
     fields_and_pk['pk'] = pk
     fields_and_pk[pk.name] = pk
     fields_and_pk.update(fields)
 
-    # Shortcut that merges both forward and reverse relationships
+    return fields_and_pk
 
-    relations = OrderedDict(
+
+def _merge_relationships(forward_relations, reverse_relations):
+    return OrderedDict(
         list(forward_relations.items()) +
         list(reverse_relations.items())
     )
-
-    return FieldInfo(pk, fields, forward_relations, reverse_relations, fields_and_pk, relations)
diff --git a/rest_framework/utils/serializer_helpers.py b/rest_framework/utils/serializer_helpers.py
index 65a04d06..87bb3ac0 100644
--- a/rest_framework/utils/serializer_helpers.py
+++ b/rest_framework/utils/serializer_helpers.py
@@ -16,6 +16,14 @@ class ReturnDict(OrderedDict):
     def copy(self):
         return ReturnDict(self, serializer=self.serializer)
 
+    def __repr__(self):
+        return dict.__repr__(self)
+
+    def __reduce__(self):
+        # Pickling these objects will drop the .serializer backlink,
+        # but preserve the raw data.
+        return (dict, (dict(self),))
+
 
 class ReturnList(list):
     """
@@ -27,6 +35,14 @@ class ReturnList(list):
         self.serializer = kwargs.pop('serializer')
         super(ReturnList, self).__init__(*args, **kwargs)
 
+    def __repr__(self):
+        return list.__repr__(self)
+
+    def __reduce__(self):
+        # Pickling these objects will drop the .serializer backlink,
+        # but preserve the raw data.
+        return (list, (list(self),))
+
 
 class BoundField(object):
     """
@@ -99,3 +115,6 @@ class BindingDict(collections.MutableMapping):
 
     def __len__(self):
         return len(self.fields)
+
+    def __repr__(self):
+        return dict.__repr__(self.fields)
diff --git a/rest_framework/utils/urls.py b/rest_framework/utils/urls.py
new file mode 100644
index 00000000..880ef9ed
--- /dev/null
+++ b/rest_framework/utils/urls.py
@@ -0,0 +1,25 @@
+from django.utils.six.moves.urllib import parse as urlparse
+
+
+def replace_query_param(url, key, val):
+    """
+    Given a URL and a key/val pair, set or replace an item in the query
+    parameters of the URL, and return the new URL.
+    """
+    (scheme, netloc, path, query, fragment) = urlparse.urlsplit(url)
+    query_dict = urlparse.parse_qs(query)
+    query_dict[key] = [val]
+    query = urlparse.urlencode(sorted(list(query_dict.items())), doseq=True)
+    return urlparse.urlunsplit((scheme, netloc, path, query, fragment))
+
+
+def remove_query_param(url, key):
+    """
+    Given a URL and a key/val pair, remove an item in the query
+    parameters of the URL, and return the new URL.
+    """
+    (scheme, netloc, path, query, fragment) = urlparse.urlsplit(url)
+    query_dict = urlparse.parse_qs(query)
+    query_dict.pop(key, None)
+    query = urlparse.urlencode(sorted(list(query_dict.items())), doseq=True)
+    return urlparse.urlunsplit((scheme, netloc, path, query, fragment))