Flask 静态文件 return 500 错误

Flask static files return 500 error

我正在尝试使用以下命令从模板 (index.html) 文件中引用静态文件。

{{ url_for('static', filename='test.css') }}

但是,我收到以下 500 错误:

127.0.0.1 - - [13/May/2018 21:34:49] "GET / HTTP/1.1" 200 -
[2018-05-13 21:34:49,603] ERROR in app: Exception on /static/test.css [GET]
Traceback (most recent call last):
  File "/Users/username/folder/flask/app.py", line 2292, in wsgi_app
    response = self.full_dispatch_request()
  File "/Users/username/folder/flask/app.py", line 1815, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/Users/username/folder/flask/app.py", line 1718, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/Users/username/folder/flask/app.py", line 1813, in full_dispatch_request
    rv = self.dispatch_request()
  File "/Users/username/folder/flask/app.py", line 1799, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/Users/username/folder/flask/helpers.py", line 976, in send_static_file
    cache_timeout=cache_timeout)
  File "/Users/username/folder/flask/helpers.py", line 713, in send_from_directory
    return send_file(filename, **options)
  File "/Users/username/folder/flask/helpers.py", line 628, in send_file
    complete_length=fsize)
  File "/Users/username/anaconda/lib/python2.7/site-packages/werkzeug/wrappers.py", line 1604, in make_conditional
    accept_ranges = _clean_accept_ranges(accept_ranges)
  File "/Users/username/anaconda/lib/python2.7/site-packages/werkzeug/wrappers.py", line 96, in _clean_accept_ranges
    raise ValueError("Invalid accept_ranges value")
ValueError: Invalid accept_ranges value
127.0.0.1 - - [13/May/2018 21:34:49] "GET /static/test.css HTTP/1.1" 500 -

奇怪的是Flask会找到并发送模板文件,但是对于静态文件会导致错误。我怀疑 Flask 可以访问 CSS 文件,但拒绝发送它。我的怀疑是基于我在尝试移动或重命名 CSS 文件时收到 404 错误。这是我的文件夹结构:

|-- web
    |-- static
        |-- test.css
    |-- templates
        |-- index.html

更新#1 这是 HTML 头部的内部结构:

<head>
  <link rel="stylesheet" type="text/css" href="{{ url_for('static', filename='test.css') }}">
  <title>Title</title>
</head>

为了方便,就用<link type="text/css" rel="stylesheet" href="/static/test.css">

我想我已经确定了错误。我正在尝试使该项目可移植,以便无法安装 Flask 的用户可以使用它。因此,我从项目中的一个目录中包含并加载 "flask"。

将目录重命名为 "flask_2" 并再次 运行 程序后,它在我通过 pip 安装的 flask 上运行完全正常。