From e8db1834d3a3f6ba05276b64e5681288aa8f9820 Mon Sep 17 00:00:00 2001
From: Tom Christie <tom@tomchristie.com>
Date: Fri, 23 Jan 2015 15:24:06 +0000
Subject: [PATCH 1/3] Added UUIDField.

---
 rest_framework/fields.py      | 18 ++++++++++++++++++
 rest_framework/serializers.py |  8 +++++++-
 tests/test_fields.py          | 18 ++++++++++++++++++
 3 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/rest_framework/fields.py b/rest_framework/fields.py
index cc9410aa7e..5e3f7ce4f3 100644
--- a/rest_framework/fields.py
+++ b/rest_framework/fields.py
@@ -23,6 +23,7 @@
 import decimal
 import inspect
 import re
+import uuid
 
 
 class empty:
@@ -632,6 +633,23 @@ def __init__(self, **kwargs):
         self.validators.append(validator)
 
 
+class UUIDField(Field):
+    default_error_messages = {
+        'invalid': _('"{value}" is not a valid UUID.'),
+    }
+
+    def to_internal_value(self, data):
+        if not isinstance(data, uuid.UUID):
+            try:
+                return uuid.UUID(data)
+            except (ValueError, TypeError):
+                self.fail('invalid', value=data)
+        return data
+
+    def to_representation(self, value):
+        return str(value)
+
+
 # Number types...
 
 class IntegerField(Field):
diff --git a/rest_framework/serializers.py b/rest_framework/serializers.py
index cf797bdcb5..dca612cad0 100644
--- a/rest_framework/serializers.py
+++ b/rest_framework/serializers.py
@@ -702,6 +702,7 @@ class ModelSerializer(Serializer):
     you need you should either declare the extra/differing fields explicitly on
     the serializer class, or simply use a `Serializer` class.
     """
+
     _field_mapping = ClassLookupDict({
         models.AutoField: IntegerField,
         models.BigIntegerField: IntegerField,
@@ -724,7 +725,8 @@ class ModelSerializer(Serializer):
         models.SmallIntegerField: IntegerField,
         models.TextField: CharField,
         models.TimeField: TimeField,
-        models.URLField: URLField,
+        models.URLField: URLField
+        # Note: Some version-specific mappings also defined below.
     })
     _related_class = PrimaryKeyRelatedField
 
@@ -1132,6 +1134,10 @@ class Meta:
         return NestedSerializer
 
 
+if hasattr(models, 'UUIDField'):
+    ModelSerializer._field_mapping[models.UUIDField] = UUIDField
+
+
 class HyperlinkedModelSerializer(ModelSerializer):
     """
     A type of `ModelSerializer` that uses hyperlinked relationships instead
diff --git a/tests/test_fields.py b/tests/test_fields.py
index 775d461848..a46cc2052e 100644
--- a/tests/test_fields.py
+++ b/tests/test_fields.py
@@ -4,6 +4,7 @@
 import datetime
 import django
 import pytest
+import uuid
 
 
 # Tests for field keyword arguments and core functionality.
@@ -467,6 +468,23 @@ class TestURLField(FieldValues):
     field = serializers.URLField()
 
 
+class TestUUIDField(FieldValues):
+    """
+    Valid and invalid values for `UUIDField`.
+    """
+    valid_inputs = {
+        '825d7aeb-05a9-45b5-a5b7-05df87923cda': uuid.UUID('825d7aeb-05a9-45b5-a5b7-05df87923cda'),
+        '825d7aeb05a945b5a5b705df87923cda': uuid.UUID('825d7aeb-05a9-45b5-a5b7-05df87923cda')
+    }
+    invalid_inputs = {
+        '825d7aeb-05a9-45b5-a5b7': ['"825d7aeb-05a9-45b5-a5b7" is not a valid UUID.']
+    }
+    outputs = {
+        uuid.UUID('825d7aeb-05a9-45b5-a5b7-05df87923cda'): '825d7aeb-05a9-45b5-a5b7-05df87923cda'
+    }
+    field = serializers.UUIDField()
+
+
 # Number types...
 
 class TestIntegerField(FieldValues):

From 5bb348605e5dad3b58495b1fc56ea393194b89fb Mon Sep 17 00:00:00 2001
From: Tom Christie <tom@tomchristie.com>
Date: Fri, 23 Jan 2015 15:31:08 +0000
Subject: [PATCH 2/3] UUIDField docs

---
 docs/api-guide/fields.md | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/docs/api-guide/fields.md b/docs/api-guide/fields.md
index b3d274ddb7..64ec902b47 100644
--- a/docs/api-guide/fields.md
+++ b/docs/api-guide/fields.md
@@ -182,6 +182,12 @@ Corresponds to `django.db.models.fields.URLField`.  Uses Django's `django.core.v
 
 **Signature:** `URLField(max_length=200, min_length=None, allow_blank=False)`
 
+## UUIDField
+
+A field that ensures the input is a valid UUID string. The `to_internal_value` method will return a `uuid.UUID` instance. On output the field will return a string in the canonical hyphenated format, for example:
+
+    "de305d54-75b4-431b-adb2-eb6b9e546013"
+
 ---
 
 # Numeric fields
@@ -320,7 +326,7 @@ Both the `allow_blank` and `allow_null` are valid options on `ChoiceField`, alth
 
 ## MultipleChoiceField
 
-A field that can accept a set of zero, one or many values, chosen from a limited set of choices. Takes a single mandatory argument. `to_internal_representation` returns a `set` containing the selected values.
+A field that can accept a set of zero, one or many values, chosen from a limited set of choices. Takes a single mandatory argument. `to_internal_value` returns a `set` containing the selected values.
 
 **Signature:** `MultipleChoiceField(choices)`
 

From 889a07f5563a0f970639a0958c0dcbc26e82919f Mon Sep 17 00:00:00 2001
From: Tom Christie <tom@tomchristie.com>
Date: Fri, 23 Jan 2015 15:32:21 +0000
Subject: [PATCH 3/3] Support assignment in ClassLookupDict

---
 rest_framework/utils/field_mapping.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/rest_framework/utils/field_mapping.py b/rest_framework/utils/field_mapping.py
index cba40d3184..c97ec5d0ed 100644
--- a/rest_framework/utils/field_mapping.py
+++ b/rest_framework/utils/field_mapping.py
@@ -38,6 +38,9 @@ def __getitem__(self, key):
                 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):
     """