python - Django 项目寻找 "attribute ' _session_cache'”

Question

所以我有一个不使用数据库的 Django 项目('DATABASES' 设置被注释掉了)。我选择使用 Django，因为将来我可能会需要数据库功能。无论如何，我已经在 tbhis 项目上断断续续地工作了几个月，没有任何问题。我正在运行 Linux Mint，到目前为止，使用 python manage.py runserver 命令没有遇到任何问题。

好吧，今天我启动了应用程序并顺利启动了本地服务器。然后我尝试在我的浏览器中打开应用程序并收到相当可怕的错误消息:

Traceback (most recent call last):
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/sessions/backends/base.py", line 170, in _get_session
    return self._session_cache
AttributeError: 'SessionStore' object has no attribute '_session_cache'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/core/handlers/base.py", line 87, in get_response
    response = middleware_method(request)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/auth/middleware.py", line 34, in process_request
    if user and hasattr(user, 'get_session_auth_hash'):
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/utils/functional.py", line 224, in inner
    self._setup()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/utils/functional.py", line 357, in _setup
    self._wrapped = self._setupfunc()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/auth/middleware.py", line 23, in <lambda>
    request.user = SimpleLazyObject(lambda: get_user(request))
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/auth/middleware.py", line 11, in get_user
    request._cached_user = auth.get_user(request)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/auth/__init__.py", line 151, in get_user
    user_id = request.session[SESSION_KEY]
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/sessions/backends/base.py", line 49, in __getitem__
    return self._session[key]
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/sessions/backends/base.py", line 175, in _get_session
    self._session_cache = self.load()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/sessions/backends/db.py", line 21, in load
    expire_date__gt=timezone.now()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/manager.py", line 92, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/query.py", line 351, in get
    num = len(clone)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/query.py", line 122, in __len__
    self._fetch_all()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/query.py", line 966, in _fetch_all
    self._result_cache = list(self.iterator())
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/query.py", line 265, in iterator
    for row in compiler.results_iter():
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/sql/compiler.py", line 700, in results_iter
    for rows in self.execute_sql(MULTI):
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/sql/compiler.py", line 775, in execute_sql
    sql, params = self.as_sql()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/sql/compiler.py", line 100, in as_sql
    out_cols, s_params = self.get_columns(with_col_aliases)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/sql/compiler.py", line 246, in get_columns
    col_aliases)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/sql/compiler.py", line 328, in get_default_columns
    r = '%s.%s' % (qn(alias), qn2(column))
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/sql/compiler.py", line 62, in __call__
    r = self.connection.ops.quote_name(name)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/backends/dummy/base.py", line 18, in complain
    raise ImproperlyConfigured("settings.DATABASES is improperly configured. "
django.core.exceptions.ImproperlyConfigured: settings.DATABASES is improperly configured. Please supply the ENGINE value. Check settings documentation for more details.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/sessions/backends/base.py", line 170, in _get_session
    return self._session_cache
AttributeError: 'SessionStore' object has no attribute '_session_cache'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3.3/wsgiref/handlers.py", line 137, in run
    self.result = application(self.environ, self.start_response)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/staticfiles/handlers.py", line 64, in __call__
    return self.application(environ, start_response)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/core/handlers/wsgi.py", line 187, in __call__
    response = self.get_response(request)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/core/handlers/base.py", line 199, in get_response
    response = self.handle_uncaught_exception(request, resolver, sys.exc_info())
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/core/handlers/base.py", line 236, in handle_uncaught_exception
    return debug.technical_500_response(request, *exc_info)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/views/debug.py", line 91, in technical_500_response
    html = reporter.get_traceback_html()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/views/debug.py", line 349, in get_traceback_html
    c = Context(self.get_traceback_data(), use_l10n=False)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/views/debug.py", line 307, in get_traceback_data
    frames = self.get_traceback_frames()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/views/debug.py", line 465, in get_traceback_frames
    'vars': self.filter.get_traceback_frame_variables(self.request, tb.tb_frame),
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/views/debug.py", line 232, in get_traceback_frame_variables
    cleansed[name] = self.cleanse_special_types(request, value)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/views/debug.py", line 187, in cleanse_special_types
    if isinstance(value, HttpRequest):
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/utils/functional.py", line 224, in inner
    self._setup()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/utils/functional.py", line 357, in _setup
    self._wrapped = self._setupfunc()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/auth/middleware.py", line 23, in <lambda>
    request.user = SimpleLazyObject(lambda: get_user(request))
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/auth/middleware.py", line 11, in get_user
    request._cached_user = auth.get_user(request)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/auth/__init__.py", line 151, in get_user
    user_id = request.session[SESSION_KEY]
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/sessions/backends/base.py", line 49, in __getitem__
    return self._session[key]
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/sessions/backends/base.py", line 175, in _get_session
    self._session_cache = self.load()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/contrib/sessions/backends/db.py", line 21, in load
    expire_date__gt=timezone.now()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/manager.py", line 92, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/query.py", line 351, in get
    num = len(clone)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/query.py", line 122, in __len__
    self._fetch_all()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/query.py", line 966, in _fetch_all
    self._result_cache = list(self.iterator())
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/query.py", line 265, in iterator
    for row in compiler.results_iter():
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/sql/compiler.py", line 700, in results_iter
    for rows in self.execute_sql(MULTI):
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/sql/compiler.py", line 775, in execute_sql
    sql, params = self.as_sql()
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/sql/compiler.py", line 100, in as_sql
    out_cols, s_params = self.get_columns(with_col_aliases)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/sql/compiler.py", line 246, in get_columns
    col_aliases)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/sql/compiler.py", line 328, in get_default_columns
    r = '%s.%s' % (qn(alias), qn2(column))
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/models/sql/compiler.py", line 62, in __call__
    r = self.connection.ops.quote_name(name)
  File "/home/peter/.virtualenvs/vis_it/lib/python3.3/site-packages/django/db/backends/dummy/base.py", line 18, in complain
    raise ImproperlyConfigured("settings.DATABASES is improperly configured. "
django.core.exceptions.ImproperlyConfigured: settings.DATABASES is improperly configured. Please supply the ENGINE value. Check settings documentation for more details.
[28/Nov/2014 13:18:54] "GET / HTTP/1.1" 500 59

自从我上次使用该应用程序以来，我就没有碰过它，当时它运行良好。我真的不知道这是在说什么，因为我没有实现缓存，也没有使用数据库……我问过一些熟悉 Django 的大学，也不知道这是什么。有任何想法吗？我还尝试根据在线帖子的建议将 DATABASES 设置为空字典 {} 但没有效果。有点不知所措。

编辑:我想我应该提一下，在我上次接触这个项目后的这段时间里，我已经开始并建立了一个使用数据库的新 Django 项目。这个项目是否有可能以某种方式被缓存并破坏了我目前正在尝试处理的项目？

EDIT2:我应该指出这个网络应用程序目前正在运行并工作在http://mrcagney-maps.com。 .代码完全一样(自从我上次推送到服务器后就没有碰过它)。真的很奇怪。

Answer 1

致 future 的 Google 员工 - 我遇到了这个问题，但上述解决方案对我不起作用。 所做 对我有用的是在 Chrome 中清除/删除 127.0.0.1 URL 的 cookie。因此，转到“设置”或按 CMD+，，然后按 Cookie 和其他站点数据，然后找到 127.0.0.1 或 localhost 并删除那些 cookie。刷新本地开发主机页面，错误应该消失了。这与损坏的 session /cookie 文件有关。