GAE标准Flask教程:ImportError:无法导入名称SpooledTemporaryFile

Question

我正在尝试使用这个GAE Flask教程.我相信我完全遵循了它,我从Github下载了代码,所以没有错别字.

当我启动dev server(dev_appserver.py app.yaml)并转到http:// localhost:8080/form时,我收到此错误:

Traceback (most recent call last):
  File "/Users/.../google-cloud-sdk/platform/google_appengine/google/appengine/runtime/wsgi.py", line 240, in Handle
    handler = _config_handle.add_wsgi_middleware(self._LoadHandler())
  File "/Users/.../google-cloud-sdk/platform/google_appengine/google/appengine/runtime/wsgi.py", line 299, in _LoadHandler
    handler, path, err = LoadObject(self._handler)
  File "/Users/.../google-cloud-sdk/platform/google_appengine/google/appengine/runtime/wsgi.py", line 85, in LoadObject
    obj = __import__(path[0])
  File "/Users/.../GIT/TEMP/main.py", line 19, in <module>
    from flask import Flask, render_template, request
  File "/Users/.../GIT/TEMP/lib/flask/__init__.py", line 17, in <module>
    from werkzeug.exceptions import abort
  File "/Users/.../GIT/TEMP/lib/werkzeug/__init__.py", line 151, in <module>
    __import__('werkzeug.exceptions')
  File "/Users/.../GIT/TEMP/lib/werkzeug/exceptions.py", line 71, in <module>
    from werkzeug.wrappers import Response
  File "/Users/.../GIT/TEMP/lib/werkzeug/wrappers.py", line 37, in <module>
    from werkzeug.formparser import FormDataParser, default_stream_factory
  File "/Users/.../GIT/TEMP/lib/werkzeug/formparser.py", line 14, in <module>
    from tempfile import SpooledTemporaryFile
ImportError: cannot import name SpooledTemporaryFile

看起来它与GAE沙箱有关,但我无法弄明白.我尝试在virtualenv的内部和外部运行开发服务器.

当使用virtualenv和app引擎时,你有什么特别的事吗？

Answer 1

本教程使用Flask版本0.12.2指定.

Flask的setup.py需要0.7版之后的任何版本的werkzeug

install_requires=[
    'Werkzeug>=0.7',
    'Jinja2>=2.4',
    'itsdangerous>=0.21',
    'click>=2.0',
],

在WERKZEUG 0.13,此承诺涉及到增加对块传输编码的支持增加进口SpooledTemporaryFile来werkzeug.formparser.

App Engine沙箱会禁用tempfile除模块之外的任何导入tempfile.TemporaryFile,因此会出错.

要解决此问题,请将werkzeug降级到版本0.12.2,该版本不包含导入.

pip install --target lib --upgrade werkzeug==0.12.2

(pip --upgrade强制安装提供的版本,因此它将降级以及升级)

或修改您的供应商要求文件以固定werkzeug版本

Flask==0.12.2
werkzeug==0.12.2

更新:

此问题现已在Google Samples Docs repo和Werkzeug v0.14中得到解决.