我在 Django 中为一个相当复杂的系统建模。我将在这里只发布它的相关部分，我将展示简化的用例图以更好地表达我的想法。
我基本上有两种类型的用户：卖家和客户。
卖家“获得”了一个客户，这意味着卖家现在拥有了客户的个人信息，并且可以与他/她进行互动。
卖家不能与他没有获得的客户互动。
卖方创建相关对象的模型层次结构（子级别中的每个模型都通过外键连接到其父级）
卖方 与一些客户共享创建的盒子对象及其所有相关对象
授权客户可以：
问题：
并非所有用户生来都是平等的。django-relationship 在任意用户之间创建任意关系，这可能不是您想要的。你真正想要的是严格限制这种关系Seller -> Customer
# This example assumes that both customers and sellers have user table entries.
from django.contrib.auth.models import User
class Customer(User): pass
class Seller(User):
acquired_customers = ManyToManyField(Customer,
related_name="acquired_sellers")
def acquire(customer):
" A convenience function to acquire customers "
self.acquired_customers.add(customer.id)
您可以使用 a 的自定义“通过”模型ManyToManyField来添加要跟踪的额外信息。在这种情况下，我们添加了卖家，以及共享时的自动时间戳。这允许您执行一些操作，例如显示已与您共享的产品（按共享时间排序），以及发送给您的卖家名称。
# Install mptt for heirararchical data.
from mptt.models import MPTTModel
class Box(MPTTModel):
" Nestable boxen for your Items "
owner = ForeignKey(Seller)
title = CharField(max_length=255)
shared_with = ManyToManyField(Customer,
related_name='boxes_sharedwithme', through=SharedBox)
class Item(Model):
" A shareable Item "
box = ForeignKey(Box)
title = CharField(max_length=255)
class SharedBox(Model):
" Keeps track of who shares what to whom, and when "
when = DateTimeField(auto_now_add=True)
box = ForeignKey(Box)
seller = ForeignKey(Seller)
customer = ForeignKey(Customer)
#----------------------------
# share an Item with a Customer
def share_item(request, box_id, customer_id, **kwargs):
# This will fail if the user is not a seller
seller = request.user.seller
# This will fail if the seller is not the owner of the item's box
box = Box.objects.get(
id=box_id, owner=seller)
# This will fail if the seller has not acquired the customer
customer = Customer.objects.get(
id=customer_id, acquired_sellers=seller)
# This will share the item if it has not already been shared.
SharedBox.objects.create_or_update(
box=box, seller=seller, customer=customer)
return HttpResponse("OK")
隐式权限是“业务逻辑”，这意味着您可能需要自己实现它。幸运的是，Django 的权限系统是可插入的，因此您可以添加自己的规则来递归层次结构来检查权限。或者，您可以创建自定义管理器，将适当的规则添加到使用的查询中。
from django.db.models import Manager
from django.db.models.query import EmptyQuerySet
class ItemManager(Manager):
def visible(user):
iqs = self.get_query_set()
oqs = EmptyQuerySet()
# add all the items a user can see as a seller
try: oqs |= iqs.filter(box__owner=user.seller)
except Seller.DoesNotExist: pass
# add all the items a user can see as a customer
try: oqs |= iqs.filter(box__shared_with=user.customer)
except Customer.DoesNotExist: pass
# return the complete list of items.
return oqs
class Item(Model): objects = ItemManager()
class ItemListView(ListView):
model = Item
def get_queryset(request):
return self.model.objects.visible(request.user)
如果这需要超级粒度或每个用户，那么 django-guardian 就是要走的路。如果权限是基于规则的，那么您最好使用一个简单的字段，以降低数据库查询的复杂性。
class Property(Model):
title = CharField(max_length=255)
units = CharField(max_length=10,
choices=UNIT_TYPES, null=True, blank=True)
# -- A simple field that toggles properties for all users
class ItemProperty(Model):
item = ForeignKey(Item)
property = ForeignKey(Property)
value = CharField(max_length=100)
customer_viewable = BooleanField(default=False)
customer_editable = BooleanField(default=False)
# -- A simple field that defines user classes who can view/edit
from django.contrib.auth.models import Group
class ItemProperty(Model):
item = ForeignKey(Item)
property = ForeignKey(Property)
value = CharField(max_length=100)
viewable_by = ForeignKey(Group)
editable_by = ForeignKey(Group)