Python pip无法找到pyodbc

Question

使用virtualenv并尝试安装pyodbc。我能找到的所有资源都声称这应该非常简单。在完成MySQL的所有基本安装之后，只需执行：

pip install pyodbc

然而，我看到一个非常奇怪的错误。它没有（据我所知）与丢失的库有关，并且在谷歌搜索这种错误很长一段时间之后，我根本找不到任何有建设性的东西。

(local-dev)espears@espears-w ~ $ pip install pyodbc
Downloading/unpacking pyodbc
  Could not find any downloads that satisfy the requirement pyodbc
  Some externally hosted files were ignored (use --allow-external pyodbc to allow).
Cleaning up...
No distributions at all found for pyodbc
Storing debug log for failure in /home/espears/.pip/pip.log

所以我尝试使用“allow-external”选项并没有帮助：

(local-dev)espears@espears-w ~ $ pip install --allow-external pyodbc
You must give at least one requirement to install (see "pip help install")

但帮助文档显示我正确使用此选项，例如从运行pip help install的输出：

Package Index Options:

...

  --allow-external <package>  Allow the installation of externally hosted files

以下是PIP日志文件中的结果：

(local-dev)espears@espears-w ~ $ cat /home/espears/.pip/pip.log
Downloading/unpacking pyodbc
  Getting page https://pypi.python.org/simple/pyodbc/
  URLs to search for versions for pyodbc:
  * https://pypi.python.org/simple/pyodbc/
  Analyzing links from page https://pypi.python.org/simple/pyodbc/
    Skipping link http://code.google.com/p/pyodbc (from https://pypi.python.org/simple/pyodbc/); not a file
    Skipping link http://code.google.com/p/pyodbc/downloads/list (from https://pypi.python.org/simple/pyodbc/); not a file
  Not searching http://code.google.com/p/pyodbc (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc/downloads/list (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc/downloads/list (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc/downloads/list (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc/downloads/list (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc/downloads/list (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc/downloads/list (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc/downloads/list (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc/downloads/list (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc/downloads/list (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc/downloads/list (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc/downloads/list (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Not searching http://code.google.com/p/pyodbc/downloads/list (from https://pypi.python.org/simple/pyodbc/) for files because external urls are disallowed.
  Could not find any downloads that satisfy the requirement pyodbc
  Some externally hosted files were ignored (use --allow-external pyodbc to allow).
Cleaning up...
  Removing temporary dir /home/espears/.virtualenvs/local-dev/build...
No distributions at all found for pyodbc
Exception information:
Traceback (most recent call last):
  File "/home/espears/.virtualenvs/local-dev/local/lib/python2.7/site-packages/pip/basecommand.py", line 122, in main
    status = self.run(options, args)
  File "/home/espears/.virtualenvs/local-dev/local/lib/python2.7/site-packages/pip/commands/install.py", line 270, in run
    requirement_set.prepare_files(finder, force_root_egg_info=self.bundle, bundle=self.bundle)
  File "/home/espears/.virtualenvs/local-dev/local/lib/python2.7/site-packages/pip/req.py", line 1157, in prepare_files
    url = finder.find_requirement(req_to_install, upgrade=self.upgrade)
  File "/home/espears/.virtualenvs/local-dev/local/lib/python2.7/site-packages/pip/index.py", line 285, in find_requirement
    raise DistributionNotFound('No distributions at all found for %s' % req)
DistributionNotFound: No distributions at all found for pyodbc

看起来如果我可以让--allow-external选项工作，它会起作用，因为它清楚地看到了获取pyodbc的常用位置。

但是我很困惑为什么要这样做，几乎所有对安装pyodbc的引用都不需要为了启用外部链接。我今天整天都在安装很多软件包，几乎没有问题，在任何其他情况下都不会遇到allow-external这个问题。

我在Ubuntu 12.04上使用pip version 1.5和Python 2.7.3。

Answer 1

如果PyPI目录结构正确，则运行pip install --allow-external pyodbc --allow-unverified pyodbc pyodbc将起作用。

基于我最初发布此答案时的pip.log输出，我认为该软件包的网站目录结构已被破坏。您始终可以通过指定pip install https://storage.googleapis.com/google-code-archive-downloads/v2/code.google.com/pyodbc/pyodbc-3.0.7.zip等软件包的URL来解决此类问题，并在here中说明不同版本的链接。

Answer 2

我刚尝试安装pyodbc并撞到同一堵墙。我认为你和我所遇到的问题是--allow-external也会消耗下一个参数。所以你实际上需要写：

sudo pip install --allow-external pyodbc pyodbc

然后我点击了另一个关于未验证来源的错误，以便实际对我有用的命令是：

sudo pip install --allow-external pyodbc --allow-unverified pyodbc pyodbc

请注意，完成后，已安装文件的权限会阻止普通用户访问pyodbc。所以我手动调整了所有已安装软件包的权限（看起来比找到pyodbc所需的文件更容易）。

cd /usr/local/lib/python2.7/
chmod -R o=g dist-packages

根据EMS的建议，我向Pip bug跟踪器添加了一个问题。它可以在：

找到

https://github.com/pypa/pip/issues/1893

Answer 3

FWIW，在ms窗口上，除了为我安装二进制文件（windows install）之外的任何东西在windows / cygwin混合环境中都很麻烦。

我选择使用pypyodbc作为纯Python，并且不需要对我的Windows / Linux开发进行任何更改。它可以被视为almost drop-in replacement for pyodbc，无需编译，当然可以使用pip install pypyodbc轻松安装。

Answer 4

使用 easy_install 在virualenv中的窗口上安装pyodbc有一种“更简单”的方法：

• 下载适用于Windows的最新pyodbc安装程序
• 激活你的virtualenv

•   

  easy_install pyodbc-3.0.7.win32-py2.7.exe

用于pywin32，请参阅：How can I use pywin32 with a virtualenv without having to include the host environment's site-packages folder?

Answer 5

与

一起安装后，我获得了成功

sudo pip install --allow-external pyodbc --allow-unverified pyodbc pyodbc

但是，我还需要unixodbc-dev包才能让pyodbc实际编译。

Answer 6

--allow-unverified和--allow-external都将包名称作为参数。

From pip help install:
--allow-external <package>   Allow the installation of a package even if it
                             is externally hosted
--allow-unverified <package> Allow the installation of a package even if it 
                             is hosted in an insecure and unverifiable way

• --allow-external需要一个参数（允许使用外部名称）。
• 同样适用于--allow-unverified。
• 使用pip install --allow-external pyodbc，您允许外部调用pyodbc

• pip install --allow-external pyodbc pydodbc是你需要的，首先pyodbc允许外部，第二个实际告诉pip要安装哪个包。

  从点子帮助安装： --allow-external允许安装包，即使它                              是外部托管的 --allow-unverified允许安装包，即使它                              

以不安全且无法核实的方式托管

所以你的用法应该是

pip install <pkg> --allow-unverified <pkg> --allow-external <pkg>

或者有点混乱：

pip install --allow-unverified <pkg> --allow-external <pkg> <pkg>

不要 使用--allow-all-external只需要一个而不是 所有 。它杀死了进行安全检查的全部目的。