在数据迁移中创建自定义权限

Question

我试图在迁移中创建自定义权限，但是在运行迁移之后，权限并未在权限 table 中创建。有人可以指出错误是什么吗？此外，我不确定我应该使用什么作为 ContentType 的相关模型，因为该权限用于限制可以查看显示网站上用户摘要的页面的用户。非常感谢任何帮助，谢谢。

def add_view_aggregated_data_permissions(apps, schema_editor):
    ContentType = apps.get_model('django', 'ContentType')
    Permission = apps.get_model('auth', 'Permission')
    content_type = ContentType.objects.get(app_label='auth', model='user')
    permission = Permission.objects.create(codename='can_view_data',
                                           name='Can view data',
                                           content_type=content_type)

Answer 1

我建议您使用 Django documentation 中描述的标准方式来使用自定义权限。您将完全避免许多问题。

To create custom permissions for a given model object, use the permissions model Meta attribute.

此示例模型创建自定义权限：

class MyModel(models.Model):
    ...
    class Meta:
        permissions = (
            ('view_data', "Can see available data"),
        )

The only thing this does is create those extra permissions when you run manage.py migrate. Your code is in charge of checking the value of these permissions when a user is trying to access the functionality provided by the application...

然后你可以在你的视图中使用 permission_required 装饰器来检查特定权限：

from django.contrib.auth.decorators import permission_required

@permission_required('myapp.view_data')
def my_view(request):
    ...

Answer 2

从 django 1.8 开始，built-in 迁移非常轻松。

您需要做的就是将您想要的权限添加到相关的型号
运行迁移

./manage.py makemigrations
运行上述步骤中创建的迁移

./manage.py 迁移

Answer 3

我想为所有应用程序模型创建自定义权限（读取）。我做了这两个步骤：

从 DjangoModelPermissions 创建扩展权限：

class DjangoModelPermissionsExtended(DjangoModelPermissions):
    """
    """
    perms_map = {
        'GET': ['%(app_label)s.read_%(model_name)s'],
        'OPTIONS': [],
        'HEAD': [],
        'POST': ['%(app_label)s.add_%(model_name)s'],
        'PUT': ['%(app_label)s.change_%(model_name)s'],
        'PATCH': ['%(app_label)s.change_%(model_name)s'],
        'DELETE': ['%(app_label)s.delete_%(model_name)s'],
    }

放在每个视图中我要读权限：

class ExampleViewSet(viewsets.ModelViewSet):
    permission_classes = (
        DjangoModelPermissionsExtended,
    )

创建 django command customread.py:

from django.core.management.base import BaseCommand, CommandError
from project.app import models as app_models
from django.db import models
from django.contrib.auth.models import Permission
from django.contrib.contenttypes.models import ContentType
import inspect

class Command(BaseCommand):
help = 'Create the read permission to app models'

def handle(self, *args, **options):
    for name, obj in inspect.getmembers(app_models):
        if inspect.isclass(obj) and issubclass(obj, models.Model):
            try:
                self.add_canread(obj)
                self.stdout.write(self.style.SUCCESS(
                    'created permission for %s' % obj
                ))
            except Exception as e:
                self.stdout.write(self.style.ERROR(
                    'Permission already exists for %s' % obj
                ))

def add_canread(self, object_class):
    """This a function that can be executed in order to create
    new permissions (read view) to a class in DB.

    """
    if inspect.isclass(object_class):
        content_type = ContentType.objects.get_for_model(object_class)
        permission = Permission.objects.create(
            codename='read_{}'.format(object_class._meta.model_name),
            name='Can view {}'.format(object_class.__name__),
            content_type=content_type,
        )
    else:
        msg = "The object is not a class"
        print(msg)

迁移后执行：
```
python manage.py customread
```

在数据迁移中创建自定义权限

Creating custom permission in data migration

django

django-permissions

django-migrations