python - 安装 Flask 时出错 - Python

Question

我仍在尝试在“虚拟环境”上安装 Flask。当 virtualenv 激活时，我在尝试获取 pip 命令时遇到了一些错误。 (我的用户名中有一个空格) 但最终找到了解决方案，只需键入 pip 所在的正确路径即可，以避免用户名文件夹。

(venv) C:\Users\Daniel P-C>cd C:\Python34\Scripts

(venv) C:\Python34\Scripts>pip

 Usage:
      pip <command> [options]
 etc...

在尝试安装 flask 时出现以下错误

(venv) C:\Python34\Scripts>pip install flask
Downloading/unpacking flask
  Running setup.py (path:C:\Users\DANIEL~1\AppData\Local\Temp\pip_build_Daniel P
-C\flask\setup.py) egg_info for package flask

    warning: no files found matching '*' under directory 'tests'
    warning: no previously-included files matching '*.pyc' found under directory
 'docs'
    warning: no previously-included files matching '*.pyo' found under directory
 'docs'
    warning: no previously-included files matching '*.pyc' found under directory
 'tests'
    warning: no previously-included files matching '*.pyo' found under directory
 'tests'
    warning: no previously-included files matching '*.pyc' found under directory
 'examples'
    warning: no previously-included files matching '*.pyo' found under directory
 'examples'
    no previously-included directories found matching 'docs\_build'
    no previously-included directories found matching 'docs\_themes\.git'
Downloading/unpacking Werkzeug>=0.7 (from flask)
  Running setup.py (path:C:\Users\DANIEL~1\AppData\Local\Temp\pip_build_Daniel P
-C\Werkzeug\setup.py) egg_info for package Werkzeug

    warning: no files found matching '*' under directory 'werkzeug\debug\templat
es'
    warning: no files found matching '*' under directory 'tests'
    warning: no previously-included files matching '*.pyc' found under directory
 'docs'
    warning: no previously-included files matching '*.pyo' found under directory
 'docs'
    warning: no previously-included files matching '*.pyc' found under directory
 'tests'
    warning: no previously-included files matching '*.pyo' found under directory
 'tests'
    warning: no previously-included files matching '*.pyc' found under directory
 'examples'
    warning: no previously-included files matching '*.pyo' found under directory
 'examples'
    no previously-included directories found matching 'docs\_build'
Downloading/unpacking Jinja2>=2.4 (from flask)
  Running setup.py (path:C:\Users\DANIEL~1\AppData\Local\Temp\pip_build_Daniel P
-C\Jinja2\setup.py) egg_info for package Jinja2

    warning: no files found matching '*' under directory 'custom_fixers'
    warning: no previously-included files matching '*' found under directory 'do
cs\_build'
    warning: no previously-included files matching '*.pyc' found under directory
 'jinja2'
    warning: no previously-included files matching '*.pyc' found under directory
 'docs'
    warning: no previously-included files matching '*.pyo' found under directory
 'jinja2'
    warning: no previously-included files matching '*.pyo' found under directory
 'docs'
Downloading/unpacking itsdangerous>=0.21 (from flask)
  Running setup.py (path:C:\Users\DANIEL~1\AppData\Local\Temp\pip_build_Daniel P
-C\itsdangerous\setup.py) egg_info for package itsdangerous

    warning: no previously-included files matching '*' found under directory 'do
cs\_build'
Downloading/unpacking markupsafe (from Jinja2>=2.4->flask)
  Downloading MarkupSafe-0.23.tar.gz
  Running setup.py (path:C:\Users\DANIEL~1\AppData\Local\Temp\pip_build_Daniel P
-C\markupsafe\setup.py) egg_info for package markupsafe

Installing collected packages: flask, Werkzeug, Jinja2, itsdangerous, markupsafe

  Running setup.py install for flask

    warning: no files found matching '*' under directory 'tests'
    warning: no previously-included files matching '*.pyc' found under directory
 'docs'
    warning: no previously-included files matching '*.pyo' found under directory
 'docs'
    warning: no previously-included files matching '*.pyc' found under directory
 'tests'
    warning: no previously-included files matching '*.pyo' found under directory
 'tests'
    warning: no previously-included files matching '*.pyc' found under directory
 'examples'
    warning: no previously-included files matching '*.pyo' found under directory
 'examples'
    no previously-included directories found matching 'docs\_build'
    no previously-included directories found matching 'docs\_themes\.git'
  Running setup.py install for Werkzeug

    warning: no files found matching '*' under directory 'werkzeug\debug\templat
es'
    warning: no files found matching '*' under directory 'tests'
    warning: no previously-included files matching '*.pyc' found under directory
 'docs'
    warning: no previously-included files matching '*.pyo' found under directory
 'docs'
    warning: no previously-included files matching '*.pyc' found under directory
 'tests'
    warning: no previously-included files matching '*.pyo' found under directory
 'tests'
    warning: no previously-included files matching '*.pyc' found under directory
 'examples'
    warning: no previously-included files matching '*.pyo' found under directory
 'examples'
    no previously-included directories found matching 'docs\_build'
  Running setup.py install for Jinja2

    warning: no files found matching '*' under directory 'custom_fixers'
    warning: no previously-included files matching '*' found under directory 'do
cs\_build'
    warning: no previously-included files matching '*.pyc' found under directory
 'jinja2'
    warning: no previously-included files matching '*.pyc' found under directory
 'docs'
    warning: no previously-included files matching '*.pyo' found under directory
 'jinja2'
    warning: no previously-included files matching '*.pyo' found under directory
 'docs'
  Running setup.py install for itsdangerous

    warning: no previously-included files matching '*' found under directory 'do
cs\_build'
  Running setup.py install for markupsafe

    building 'markupsafe._speedups' extension
    ==========================================================================
    WARNING: The C extension could not be compiled, speedups are not enabled.
    Failure information, if any, is above.
    Retrying the build without the C extension now.


    ==========================================================================
    WARNING: The C extension could not be compiled, speedups are not enabled.
    Plain-Python installation succeeded.
    ==========================================================================
Successfully installed flask Werkzeug Jinja2 itsdangerous markupsafe
Cleaning up...

它说它已经成功安装了 flask，但是当运行 python 并尝试输入 import flask 时，它好像没有安装？我能做什么？

(venv) C:\Python34\Scripts>python
Python 3.4.1 (v3.4.1:c0e311e010fc, May 18 2014, 10:38:22) [MSC v.1600 32 bit (In
tel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import flask
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: No module named 'flask'

顺便说一句，我在 Windows 7 上运行

Answer 1

请确定，您使用来自 venv 的 pip 和 python

对于要通过 pip 安装到 virtualenv 的模块/包，您必须使用来自 virtualenv 的 pip。

要将正在安装的模块/包导入到 virtualenv 环境中，您必须从给定的 virtualenv 运行 python 解释器。

如果您从目录 C:\Python 34\Scripts 运行您的 pip 或 python，很可能您使用系统范围的 pip 并将 flask 安装到系统 Python 中。在 Linux 上你会遇到问题，因为安装到系统范围的 python 需要 root 权限，在 MS Windows 默认 Python 安装上它不会提示。

建议:从默认的 Python 安装目录创建你的 virtualenv，并使用来自这个 virtulaenv 的 pip 和 python。这是通常发生的情况，当您激活 virtualenv 时，因此无需显式使用 pip 或 python 的完整路径(无论如何，使用 venv 的显式路径 python 和 pip 不会造成任何伤害。