ImportError：没有名为 _ctypes 的模块。具有散景图的 Google 应用引擎

Question

• Python 2.7.13
• Windows 10 64 位

我一直在处理这个Udacity web dev course 并想尝试使用this example 将简单的散景图嵌入到网页中。运行 dev_appserver.py 给出错误：ImportError: No module named _ctypes

我有：

• 通过 pip 安装 Bokeh 和 Numpy
• 在 app.yaml 中包含 Numpy

This answer 声明 Google App Engine 不允许导入 ctypes。但是，我不确定如何确认 Bokeh 是否属于这种情况。这个错误是由 Bokeh 导入 ctypes 引起的吗？如果是这样，有解决办法吗？

ERROR    2017-01-21 19:14:53,799 wsgi.py:263]
Traceback (most recent call last):
  File "C:\Users\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\google\appengine\runtime\wsgi.py", line 240, in Handle
    handler = _config_handle.add_wsgi_middleware(self._LoadHandler())
  File "C:\Users\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\google\appengine\runtime\wsgi.py", line 299, in _LoadHandler
    handler, path, err = LoadObject(self._handler)
  File "C:\Users\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\google\appengine\runtime\wsgi.py", line 85, in LoadObject
    obj = __import__(path[0])
  File "C:\Users\Google Drive\Udacity web development 2017\udacit
y-cs253\bokeh\1_docs_example\main.py", line 2, in <module>
    from bokeh.plotting import figure
  File "C:\Users\Google Drive\Udacity web development 2017\udacit
y-cs253\bokeh\1_docs_example\lib\bokeh\plotting\__init__.py", line 2, in <module
>
    from ..document import Document; Document
  File "C:\Users\Google Drive\Udacity web development 2017\udacit
y-cs253\bokeh\1_docs_example\lib\bokeh\document.py", line 45, in <module>
    from .core.json_encoder import serialize_json
  File "C:\Users\Google Drive\Udacity web development 2017\udacit
y-cs253\bokeh\1_docs_example\lib\bokeh\core\json_encoder.py", line 43, in <modul
e>
    import numpy as np
  File "C:\Users\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\google\appengine\tools\devappserver2\python\sandbox.py", line
706, in load_module
    module = self._find_and_load_module(fullname, fullname, [module_path])
  File "C:\Users\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\google\appengine\tools\devappserver2\python\sandbox.py", line
447, in _find_and_load_module
    return imp.load_module(fullname, source_file, path_name, description)
  File "D:\Python27\lib\numpy\__init__.py", line 142, in <module>
    from . import add_newdocs
INFO     2017-01-21 19:14:53,859 module.py:806] default: "GET / HTTP/1.1" 500 -
  File "D:\Python27\lib\numpy\add_newdocs.py", line 13, in <module>
    from numpy.lib import add_newdoc
  File "D:\Python27\lib\numpy\lib\__init__.py", line 8, in <module>
    from .type_check import *
  File "D:\Python27\lib\numpy\lib\type_check.py", line 11, in <module>
    import numpy.core.numeric as _nx
  File "D:\Python27\lib\numpy\core\__init__.py", line 33, in <module>
    from . import _internal  # for freeze programs
  File "D:\Python27\lib\numpy\core\_internal.py", line 14, in <module>
    import ctypes
  File "D:\Python27\lib\ctypes\__init__.py", line 7, in <module>
    from _ctypes import Union, Structure, Array
  File "C:\Users\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\google\appengine\tools\devappserver2\python\sandbox.py", line
964, in load_module
    raise ImportError('No module named %s' % fullname)
ImportError: No module named _ctypes

app.yaml：

runtime: python27
api_version: 1
threadsafe: true

handlers:
- url: /.*
  script: main.app

libraries:
- name: jinja2
  version: latest
- name: numpy
  version: latest

main.py

import os, webapp2, jinja2
from bokeh.plotting import figure
from bokeh.embed import components

plot = figure()
plot.circle([1,2], [3,4])
script, div = components(plot)

template_dir = os.path.join(os.path.dirname(__file__), 'templates')
jinja_env = jinja2.Environment(loader = jinja2.FileSystemLoader(template_dir),
                                autoescape = True)

class Handler(webapp2.RequestHandler):
    def write(self, *a, **kw):
        self.response.write(*a, **kw)

    def render_str(self, template, **kw):
        t = jinja_env.get_template(template)
        return t.render(kw)

    def render(self, template, **kw):
        self.write(self.render_str(template, **kw))

class MainPage(Handler):
    def get(self):
        self.render("chart.html", script = script, div = div)

app = webapp2.WSGIApplication([
    ('/', MainPage),
], debug=True)

chart.html

{% extends "base.html" %}

{% block content %}

<!-- Load BokehJS -->
<link
    href="http://cdn.bokeh.org/bokeh/release/bokeh-0.12.0.min.css"
    rel="stylesheet" type="text/css">
<link
    href="http://cdn.bokeh.org/bokeh/release/bokeh-widgets-0.12.0.min.css"
    rel="stylesheet" type="text/css">

<script src="http://cdn.bokeh.org/bokeh/release/bokeh-0.12.0.min.js"></script>
<script src="http://cdn.bokeh.org/bokeh/release/bokeh-widgets-0.12.0.min.js"></script>

{{ script }}
{{ div }}

{% endblock %}

base.html

<!DOCTYPE html>
<html>
<head>
    <title>Udacity Templates!</title>
</head>
<body style="margin: 0">
    <h1 style="background-color: #ddd; color: #888; margin: 0; height: 50px">Udacity Templates</h1>
    {% block content %}
    {% endblock %}
</body>
</html>

gcloud 版本

• 谷歌云 SDK 139.0.1
• app-engine-python 1.9.49
• bq 2.0.24
• bq-win 2.0.24
• 捆绑-python 2.7.10
• 核心2017.01.12
• 芯赢2016.11.07
• gcloud
• gsutil 4.22
• gsutil-win 4.20
• powershell 1.0.0.1
• windows-ssh-tools 2016.05.13

更新 1： 我已经卸载了 numpy 1.12.0 并安装了 numpy 1.6.1。我现在收到此错误：

NP_MS_DELTA = np.timedelta64(1, 'ms')
TypeError: function takes at most 1 argument (2 given)

This 声明 numpy 1.6.1 无法在标量构造函数中指定单位。这是否意味着 Bokeh 依赖于 numpy>1.6.1？

ERROR    2017-01-22 10:37:45,980 wsgi.py:263]
Traceback (most recent call last):
  File "C:\Users\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\google\appengine\runtime\wsgi.py", line 240, in Handle
    handler = _config_handle.add_wsgi_middleware(self._LoadHandler())
  File "C:\Users\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\google\appengine\runtime\wsgi.py", line 299, in _LoadHandler
    handler, path, err = LoadObject(self._handler)
  File "C:\Users\AppData\Local\Google\Cloud SDK\google-cloud-sdk\platform
\google_appengine\google\appengine\runtime\wsgi.py", line 85, in LoadObject
    obj = __import__(path[0])
  File "C:\Users\Google Drive\Udacity web development 2017\udacit
y-cs253\bokeh\1_docs_example\main.py", line 2, in <module>
    from bokeh.plotting import figure
  File "C:\Users\Google Drive\Udacity web development 2017\udacit
y-cs253\bokeh\1_docs_example\lib\bokeh\plotting\__init__.py", line 2, in <module
>
    from ..document import Document; Document
  File "C:\Users\Google Drive\Udacity web development 2017\udacit
y-cs253\bokeh\1_docs_example\lib\bokeh\document.py", line 45, in <module>
    from .core.json_encoder import serialize_json
  File "C:\Users\Google Drive\Udacity web development 2017\udacit
y-cs253\bokeh\1_docs_example\lib\bokeh\core\json_encoder.py", line 53, in <modul
e>
    NP_MS_DELTA = np.timedelta64(1, 'ms')
TypeError: function takes at most 1 argument (2 given)
INFO     2017-01-22 10:37:46,170 module.py:806] default: "GET / HTTP/1.1" 500 -

更新 2：

这让我想起了我 pip 安装 Bokeh 的时候。下载它的依赖 numpy 时，它似乎依赖于 numpy>=1.7.1：

Collecting numpy>=1.7.1 (from Bokeh)

Answer 1

在此处从 google 发布解决方法：

https://issuetracker.google.com/issues/38290292

• 转到<sdk_root>\google\appengine\tools\devappserver2\python\sandbox.py

• 找到_WHITE_LIST_C_MODULES = [xxx]的定义
  将以下两行添加到列表中：

  '_winreg',
  '_ctypes',
  

• 再次尝试您的应用。

为我工作。

Answer 2

我设法让开发服务器运行使用 2 hacks

ImportError: No module named _ctypes

这其实是flask造成的 New Flask 使用名为 click 的库，它使用 ctypes Gae 不允许 ctypes 解决方案： 使用

安装和旧版本的 click

pip install --target lib --upgrade click==5.1

这修复了 ctypes 但会导致另一个错误

ImportError: No module named msvcrt

通过将此行添加到 appengine_config.py（与 app.yaml 位于同一文件夹中）可以轻松解决此问题

import os, sys

on_appengine = os.environ.get('SERVER_SOFTWARE','').startswith('Development')
if on_appengine and os.name == 'nt':
    sys.platform = "Not Windows"

在此开发服务器启动并运行后

Answer 3

这对我来说在 14.04LTS 和基本内核 4.1+ 上运行良好......在安装 python3.7 时：

sudo apt-get install libffi-dev

Answer 4

编辑：请参阅下面的答案以了解 Google 提供的新解决方法。

---

我可以明确地说，Bokeh 本身在库中的任何地方都不会直接使用ctypes。但它确实使用了 NumPy，而且似乎至少某些版本的 NumPy 确实使用了ctypes？这个链接：

http://kawahara.ca/using-numpy-on-google-app-engine-with-the-anaconda-python-distribution/

似乎表明 GAE 仅 1.6 版的 NumPy 受支持。我可能会认为这是因为该版本不使用 ctypes，或者因为 Google 已明确将该版本列入白名单，以某种方式可接受。

所以建议是专门安装 NumPy 1.6，而不是最新版本（使用 pip 或 conda 或其他）。

Answer 5

您可以将包 six 添加到您的 requirements.txt 对我来说这个修复

pip install -t lib/ six