Python Django项目正在寻找；属性'_会话缓存&x27&引用；

因此，我有一个Django项目，它不使用数据库（“数据库”设置被注释掉）。我选择使用Django，因为将来可能需要数据库功能。不管怎样，我在这个项目上下忙了几个月，没有任何问题。我正在运行LinuxMint，到目前为止，我在使用

python manage.py runserver

命令时没有遇到任何问题

今天我启动了应用程序，启动了本地服务器，没有任何问题。然后，我尝试在浏览器中打开应用程序，收到了一条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

回溯（最近一次呼叫最后一次）：
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/contrib/sessions/backends/base.py”，第170行，在获取会话中
返回self.\u会话\u缓存
AttributeError:“SessionStore”对象没有属性“\u会话\u缓存”
在处理上述异常期间，发生了另一个异常：
回溯（最近一次呼叫最后一次）：
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/core/handlers/base.py”，第87行，在get_响应中
响应=中间件\方法（请求）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/contrib/auth/middleware.py”，第34行，正在处理中
如果user和hasattr（user'get\u session\u auth\u hash'）：
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/utils/functional.py”，第224行，内部
self.\u设置（）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/utils/functional.py”，第357行，在安装程序中
self.\u wrapped=self.\u setupfunc（）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/contrib/auth/middleware.py”，第23行，在
request.user=SimpleLazyObject（lambda:get_user（request））
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/contrib/auth/middleware.py”，第11行，在get_user中
请求。_cached_user=auth.get_user（请求）
文件“/home/peter/.virtualenvs/vis_-it/lib/python3.3/site-packages/django/contrib/auth/_-init__;.py”，第151行，在get_-user中
user\u id=request.session[session\u KEY]
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/contrib/sessions/backends/base.py”，第49行，在u getitem中__
返回self.\u会话[键]
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/contrib/sessions/backends/base.py”，第175行，在获取会话中
self.\u session\u cache=self.load（）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/contrib/sessions/backends/db.py”，第21行，已加载
expire\u date\uu gt=timezone.now（）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/db/models/manager.py”，第92行，在manager_方法中
返回getattr（self.get_queryset（），name）（*args，**kwargs）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/db/models/query.py”，get中第351行
num=len（克隆）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/db/models/query.py”，第122行，在__
self._fetch_all（）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/db/models/query.py”，第966行，在_fetch_all中
self.\u result\u cache=list（self.iterator（））
迭代器中的文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/db/models/query.py”，第265行
对于编译器.results\u iter（）中的行：
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/db/models/sql/compiler.py”，第700行，结果文件
对于self.execute_sql（多）中的行：
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/db/models/sql/compiler.py”，第775行，在execute_sql中
sql，params=self.as_sql（）
as_sql中的文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/db/models/sql/compiler.py”，第100行
out_cols，s_params=self.get_列（带_col_别名）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/db/models/sql/compiler.py”，第246行，在get_列中
col_（别名）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/db/models/sql/compiler.py”，第328行，在get_default_列中
r=“%s.%s%”（qn（别名），qn2（列））
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/db/models/sql/compiler.py”，第62行，在调用中__
r=自连接操作引用名称（名称）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/db/backends/dummy/base.py”，第18行
raise配置不正确（“settings.DATABASES配置不正确。”
django.core.exceptions.ImpropertlyConfigured:设置。数据库配置不正确。请提供引擎值。有关详细信息，请查看设置文档。
在处理上述异常期间，发生了另一个异常：
回溯（最近一次呼叫最后一次）：
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/contrib/sessions/backends/base.py”，第170行，在获取会话中
返回self.\u会话\u缓存
AttributeError:“SessionStore”对象没有属性“\u会话\u缓存”
在处理上述异常期间，发生了另一个异常：
回溯（最近一次呼叫最后一次）：
文件“/usr/lib/python3.3/wsgiref/handlers.py”，第137行，运行中
self.result=应用程序（self.environ、self.start\u响应）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/contrib/staticfiles/handlers.py”，第64行，在调用中__
返回self.application（环境、启动和响应）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/core/handlers/wsgi.py”，第187行，在调用中__
响应=自我获取响应（请求）
文件“/home/peter/.virtualenvs/vis_it/lib/python3.3/site packages/django/core/handlers/base.py”，第199行，在get_响应中
响应=self.handle\u uncaught\u异常（请求、解析器、sys.exc\u i
python manage.py makemigrations
python manage.py migrate

python manage.py createsuperuser

python manage.py runserver

# from the shell but equivalent sql would work fine too
from django.contrib.sessions.models import Session
Session.objects.all().delete()