在 Pyramid 中使用静态资产时来自 pkg_resources 的 TypeError

问题描述

尝试在 Pyramid 应用上设置静态资产。我使用了以下调用：

config.add_static_view(name='static',path='toolsofknowledge:static')

文件 main.css 按预期存储在 toolsofknowledge/static/main.css 下。 toolsofknowledge 软件包通过可编辑的链接在本地安装，使用 pip3 install -e .。

使用 curl 请求 http://localhost:8080/static/main.css 会导致服务器出现此异常：

amoe@cslp019129 $ PYRAMID_RELOAD_TEMPLATES=1 pserve3 --reload development.ini
Starting monitor for PID 3796.
Starting server in PID 3796.
Serving on http://localhost:8080
Serving on http://localhost:8080
ERROR:waitress:Exception when serving /static/main.css
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/pyramid/tweens.py",line 13,in _error_handler
    response = request.invoke_exception_view(exc_info)
  File "/usr/lib/python3/dist-packages/pyramid/view.py",line 769,in invoke_exception_view
    raise HTTPNotFound
pyramid.httpexceptions.HTTPNotFound: The resource could not be found.

During handling of the above exception,another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/waitress/channel.py",line 336,in service
    task.service()
  File "/usr/lib/python3/dist-packages/waitress/task.py",line 175,in service
    self.execute()
  File "/usr/lib/python3/dist-packages/waitress/task.py",line 452,in execute
    app_iter = self.channel.server.application(env,start_response)
  File "/usr/lib/python3/dist-packages/pyramid/router.py",line 270,in __call__
    response = self.execution_policy(environ,self)
  File "/usr/lib/python3/dist-packages/pyramid/router.py",line 279,in default_execution_policy
    return request.invoke_exception_view(reraise=True)
  File "/usr/lib/python3/dist-packages/pyramid/view.py",line 768,in invoke_exception_view
    reraise_(*exc_info)
  File "/usr/lib/python3/dist-packages/pyramid/compat.py",line 179,in reraise
    raise value
  File "/usr/lib/python3/dist-packages/pyramid/router.py",line 277,in default_execution_policy
    return router.invoke_request(request)
  File "/usr/lib/python3/dist-packages/pyramid/router.py",line 249,in invoke_request
    response = handle_request(request)
  File "/usr/lib/python3/dist-packages/pyramid/tweens.py",line 43,in excview_tween
    response = _error_handler(request,exc)
  File "/usr/lib/python3/dist-packages/pyramid/tweens.py",line 17,in _error_handler
    reraise(*exc_info)
  File "/usr/lib/python3/dist-packages/pyramid/compat.py",in reraise
    raise value
  File "/usr/lib/python3/dist-packages/pyramid/tweens.py",line 41,in excview_tween
    response = handler(request)
  File "/usr/lib/python3/dist-packages/pyramid/router.py",line 148,in handle_request
    registry,request,context,context_iface,view_name
  File "/usr/lib/python3/dist-packages/pyramid/view.py",line 657,in _call_view
    response = view_callable(context,request)
  File "/usr/lib/python3/dist-packages/pyramid/viewderivers.py",line 401,in viewresult_to_response
    result = view(context,request)
  File "/usr/lib/python3/dist-packages/pyramid/static.py",line 102,in __call__
    if resource_isdir(self.package_name,resource_path):
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py",line 1138,in resource_isdir
    return get_provider(package_or_requirement).resource_isdir(
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py",line 364,in get_provider
    return _find_adapter(_provider_factories,loader)(module)
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py",line 1392,in __init__
    self.module_path = os.path.dirname(getattr(module,'__file__',''))
  File "/usr/lib/python3.7/posixpath.py",line 156,in dirname
    p = os.fspath(p)
TypeError: expected str,bytes or os.PathLike object,not NoneType

Python 3.7，金字塔 1.10.2。

解决方法

解决方案：将 __init__.py 添加到 toolsofknowledge 目录。

问题很简单——toolsofknowledge 包虽然已安装但不是真正的包，因为它缺少 __init__.py。这会导致 toolsofknowledge.__loader__ 成为 NamespaceLoader 的实例，而它应该是 SourceFileLoader。显然，pkg_resources 无法解析与非真实包相关的资源。可以说它应该更顺利地处理这种情况。