August 2018
Intermediate to advanced
230 pages
6h 42m
Chinese
Content preview from Flask Web开发：基于Python的Web应用开发实战（第2版）
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用户角色
｜
101
9.3
检验角色
为了简化角色和权限的实现过程，可在 User 模型中添加一个辅助方法，检查赋予用户的角
色是否有某项权限。这个辅助方法的实现很简单，直接委托前面添加的权限管理方法，如
示例
9-6
所示。
示例
9-6
app/models.py
：检查用户是否有指定的权限
from flask_login import UserMixin, AnonymousUserMixin
class User(UserMixin, db.Model):
# ...
def can(self, perm):
return self.role is not None and self.role.has_permission(perm)
def is_administrator(self):
return self.can(Permission.ADMIN)
class AnonymousUser(AnonymousUserMixin):
def can(self, permissions):
return False
def is_administrator(self):
return False
login_manager.anonymous_user = AnonymousUser
如果角色中包含请求的权限，那么 User 模型中添加的 can() 方法会返回 True，表示允
许用户执行此项操作。因为经常需要检查是否具有管理员权限，所以还单独实现了
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.