UUIDField does not validate query value

[Alex Rothberg]

I have two models one with an int pk and one with a UUIDField pk:

class Bar(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid4)

class Bar2(models.Model):
    pass

If I try to get these using a value of {} they fail differently. The model with the int pk:

>>> Bar2.objects.all().get(pk={})
TypeError: int() argument must be a string or a number, not 'dict'

whereas:

>>> Bar.objects.all().get(pk={})
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "/Users/alex/.virtualenvs/TestPG/lib/python2.7/site-packages/django/db/models/query.py", line 328, in get
    num = len(clone)
  File "/Users/alex/.virtualenvs/TestPG/lib/python2.7/site-packages/django/db/models/query.py", line 144, in __len__
    self._fetch_all()
  File "/Users/alex/.virtualenvs/TestPG/lib/python2.7/site-packages/django/db/models/query.py", line 965, in _fetch_all
    self._result_cache = list(self.iterator())
  File "/Users/alex/.virtualenvs/TestPG/lib/python2.7/site-packages/django/db/models/query.py", line 238, in iterator
    results = compiler.execute_sql()
  File "/Users/alex/.virtualenvs/TestPG/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 840, in execute_sql
    cursor.execute(sql, params)
  File "/Users/alex/.virtualenvs/TestPG/lib/python2.7/site-packages/django/db/backends/utils.py", line 79, in execute
    return super(CursorDebugWrapper, self).execute(sql, params)
  File "/Users/alex/.virtualenvs/TestPG/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/Users/alex/.virtualenvs/TestPG/lib/python2.7/site-packages/django/db/utils.py", line 97, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File "/Users/alex/.virtualenvs/TestPG/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/Users/alex/.virtualenvs/TestPG/lib/python2.7/site-packages/django/db/backends/sqlite3/base.py", line 318, in execute
    return Database.Cursor.execute(self, query, params)
InterfaceError: Error binding parameter 0 - probably unsupported type.

This inconsistency leads to issues like: ​https://github.com/tomchristie/django-rest-framework/issues/2970

[Tim Graham]

Accepting in a similar vein to #24319. Here's a test that can be used to reproduce the issue:

tests/model_fields/test_uuid.py

@@ -37 +37 @@
         loaded = NullableUUIDModel.objects.get()
         self.assertEqual(loaded.field, None)
 
+    def test_pk_validated(self):
+        PrimaryKeyUUIDModel.objects.get(pk={})
+
     def test_wrong_value(self):
         self.assertRaisesMessage(
             ValueError, 'badly formed hexadecimal UUID string',

[Cole Maclean]

​https://github.com/django/django/pull/4758 should fix this.

[Cole Maclean]

OK, patch revised.

[Tim Graham <timograham@…>]

In 20ff296:

Fixed #24859 -- Made QuerySet.get() with UUIDField raise TypeError on bad value.

For consistency with AutoField.