django 1.8测试模型和迁移

Question

我使用django 1.8我有一个模型参考django.contrib.contenttypes.ContentType:

from django.db import models
from django.contrib.contenttypes.fields import GenericForeignKey
from django.contrib.contenttypes.models import ContentType


class TaggedItem(models.Model):
    tag = models.SlugField()
    content_type = models.ForeignKey(ContentType)
    object_id = models.PositiveIntegerField()
    content_object = GenericForeignKey('content_type', 'object_id')

    def __str__(self):              # __unicode__ on Python 2
        return self.tag

我有一个tests.py:

class TestObj(models.Model):
    value = models.IntegerField(default=42, null=False)

    def __str__(self):
        text = "%s-%i" % ("name", self.value)
        return text


class MyUnitTest(TestCase):
    def setUp(self):
        TestObj.objects.create(value=40)
        TestObj.objects.create()

    def test_my_test(self):
        obj1 = TestObj.objects.get(value=40)
        obj2 = TestObj.objects.get(value=42)
        self.assertEqual(obj1.value, 40)
        self.assertEqual(obj2.value, 42)

当我尝试在没有迁移的情况下创建数据库(以及"测试")时,我收到一个带有无效引用的错误:

./manage.py syncdb
...
django.db.utils.ProgrammingError: ERROR: reference "django_content_type" does not exist

但是如果我创建一个迁移(./manage.py makemigrations myobj),迁移只包含models.py模型(TaggedItem):

Migrations for 'myobj':
  0001_initial.py:
    - Create model TaggedItem

在我尝试测试我的应用程序后,我收到错误,引用myob_testobj不存在:

./manage.py test -v3
Creating test database for alias 'default' ('testdb_49308_4288843')...
Operations to perform:
  Synchronize unmigrated apps: staticfiles
  Apply all migrations: myobj, contenttypes, sessions
Synchronizing apps without migrations:
Running pre-migrate handlers for application contenttypes
Running pre-migrate handlers for application sessions
Running pre-migrate handlers for application myobj
  Creating tables...
    Running deferred SQL...
  Installing custom SQL...
Loading 'initial_data' fixtures...
Checking 'mypro' for fixtures...
No fixture 'initial_data' in 'mypro'.
Installed 0 object(s) from 0 fixture(s)
Running migrations:
  Rendering model states... DONE (0.010s)
  Applying contenttypes.0001_initial... OK (0.133s)
  Applying contenttypes.0002_remove_content_type_name... OK (0.017s)
  Applying myobj.0001_initial... OK (0.217s)
  Applying sessions.0001_initial... OK (0.233s)
Running post-migrate handlers for application contenttypes
Adding content type 'contenttypes | contenttype'
Running post-migrate handlers for application sessions
Adding content type 'sessions | session'
Running post-migrate handlers for application myobj
Adding content type 'myobj | taggeditem'
Adding content type 'myobj | testobj'
Traceback
...
django.db.utils.ProgrammingError: ERROR: reference "myobj_testobj" does not exist

如果我不使用迁移并运行测试,则表myobj_testobj已创建,但是我收到错误而没有引用"django_content_type"

/manage.py test -v3
Creating test database for alias 'default' ('testdb_773982_6463361')...
Operations to perform:
  Synchronize unmigrated apps: staticfiles, myobj
  Apply all migrations: contenttypes, sessions
Synchronizing apps without migrations:
Running pre-migrate handlers for application contenttypes
Running pre-migrate handlers for application sessions
Running pre-migrate handlers for application myobj
  Creating tables...
    Creating table myobj_taggeditem
    **Creating table myobj_testobj**
    Running deferred SQL...
Traceback
...
django.db.utils.ProgrammingError: ERROR: reference "django_content_type" does not exist

如何在模型中使用测试？谢谢.

Answer 1

您需要在 Django 1.7 或更高版本上使用迁移。Syncdb 已被弃用，不应再使用。

相反，您应该使用 makemigrations，然后使用 migrate。

您看到此错误的原因是，当您运行syncdb时，它不会运行ContentTypes迁移，因此数据库中不存在这些模型。运行单元测试时，Django 会自动执行 migrate 命令，这可以解释为什么它在单元测试中有效，但在开发服务器上手动运行时无效。