将Flask-security实例导入我的视图模块会破坏我的webapp

Question

我正在为电子商务网站编写注册/登录系统,并使用flask-security(http://pythonhosted.org/Flask-Security/)来处理注册功能.部分基本设置需要以下signup.py模块:

from flask.ext.security import SQLAlchemyUserDatastore, Security
from app.models import User, Role
from app import app, db

# Setup Flask Security
user_datastore = SQLAlchemyUserDatastore(db, User, Role)
security = Security(app, user_datastore)

然后我必须将user_datastore和安全对象导入到views.py模块中,如下所示:

from app.signup import user_datastore, security

问题是,只要我将上面的import语句包含到我的视图模块中,我的整个应用程序崩溃了,当我尝试运行我的单元或行为测试时,我得到以下回溯错误(为了便于阅读而编辑)

======================================================================
ERROR: Failure: AttributeError ('_FakeSignal' object has no attribute 'connect_via')
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Library/Python/2.7/site-packages/nose/loader.py", line 413, in loadTestsFromName
    addr.filename, addr.module)
  File "/Library/Python/2.7/site-packages/nose/importer.py", line 47, in importFromPath
    return self.importFromDir(dir_path, fqname)
  File "/Library/Python/2.7/site-packages/nose/importer.py", line 94, in importFromDir
    mod = load_module(part_fqname, fh, filename, desc)
  File "/Users/faiyamrahman/programming/Python/WebApps/NibsNWhiskeyFull/tests/test_database.py", line 6, in <module>
    from app import app, db, models
  File "/Users/faiyamrahman/programming/Python/WebApps/NibsNWhiskeyFull/app/__init__.py", line 9, in <module>
    from app import views, models
  File "/Users/faiyamrahman/programming/Python/WebApps/NibsNWhiskeyFull/app/views.py", line 7, in <module>
    from app.signup import user_datastore
  File "/Users/faiyamrahman/programming/Python/WebApps/NibsNWhiskeyFull/app/signup.py", line 7, in <module>
    security = Security(app, user_datastore)
  File "/Users/faiyamrahman/programming/Python/WebApps/NibsNWhiskeyFull/flask/lib/python2.7/site-packages/flask_security/core.py", line 346, in __init__
    self._state = self.init_app(app, datastore, **kwargs)
  File "/Users/faiyamrahman/programming/Python/WebApps/NibsNWhiskeyFull/flask/lib/python2.7/site-packages/flask_security/core.py", line 368, in init_app
    identity_loaded.connect_via(app)(_on_identity_loaded)
AttributeError: '_FakeSignal' object has no attribute 'connect_via'

我不知道这是什么意思.我试过阅读烧瓶安全文档,但我不明白为什么会这样.感谢任何对此进行刺杀的人!

Answer 1

简答:你缺少闪光库. 编辑:您确认您的虚拟环境找不到闪烁,并重新安装它.

答案很长:

我认为错误来自Flask Signals.从信号中查看此代码:

signals_available = False
try:
    from blinker import Namespace
    signals_available = True
except ImportError:
    class Namespace(object):
        def signal(self, name, doc=None):
            return _FakeSignal(name, doc)

所以我认为代码试图找到blinker库,在你的情况下,它无法导入它,因此它尝试使用_FakeSignal该类.

该_FakeSignal班没有一个connect_via属性定义为你可以看到下面

class _FakeSignal(object):
    """If blinker is unavailable, create a fake class with the same
    interface that allows sending of signals but will fail with an
    error on anything else.  Instead of doing anything on send, it
    will just ignore the arguments and do nothing instead.
    """

    def __init__(self, name, doc=None):
        self.name = name
        self.__doc__ = doc
    def _fail(self, *args, **kwargs):
        raise RuntimeError('signalling support is unavailable '
                           'because the blinker library is '
                           'not installed.')
    send = lambda *a, **kw: None
    connect = disconnect = has_receivers_for = receivers_for = \
        temporarily_connected_to = connected_to = _fail
    del _fail

connect_viaFlask-Security尝试加载的属性实际上是由blinker库提供的,因为没有闪烁,没有connect_via.因此它失败了.

所以你应该先安装闪光灯.但是,我认为Flask-Security代码blinker在尝试使用之前也应该检查connect_via.