Error: Can't find Python executable, you can set the PYTHON env variable.

该错误解决方案。

NodeJS安装Npm包时出现错误：

npm WARN prefer global node-gyp@3.4.0 should be installed with -g

> snappy@5.0.5 install C:\code\myprj\node_modules\snappy
> node-gyp rebuild

C:\code\myprj\node_modules\snappy>if not defined npm_config_node_gyp (node "C:\Program Files\nodejs\node_modules\npm\bin\node-gyp-bin\\..\..\node_modules\node-gyp\bin\node-gyp.js" rebuild )  else (node "" rebuild )
gyp ERR! configure error
gyp ERR! stack Error: Can't find Python executable "C:\Users\jun\AppData\Local\Programs\Python\Python36", you can set the PYTHON env variable.
gyp ERR! stack     at PythonFinder.failNoPython (C:\Program Files\nodejs\node_modules\npm\node_modules\node-gyp\lib\configure.js:483:19)
gyp ERR! stack     at PythonFinder.<anonymous> (C:\Program Files\nodejs\node_modules\npm\node_modules\node-gyp\lib\configure.js:508:16)
gyp ERR! stack     at C:\Program Files\nodejs\node_modules\npm\node_modules\graceful-fs\polyfills.js:284:29
gyp ERR! stack     at FSReqWrap.oncomplete (fs.js:152:21)
gyp ERR! System Windows_NT 6.1.7601
gyp ERR! command "C:\\Program Files\\nodejs\\node.exe" "C:\\Program Files\\nodejs\\node_modules\\npm\\node_modules\\node-gyp\\bin\\node-gyp.js" "rebuild"
gyp ERR! cwd C:\code\myprj\node_modules\snappy
gyp ERR! node -v v8.1.3
gyp ERR! node-gyp -v v3.6.2
gyp ERR! not ok

> deasync@0.1.9 install C:\code\myprj\node_modules\deasync
> node ./build.js

大致意思是python没有环境变量，但实际上已经安装了python也配置了环境变量，可就是解决不了。

如果遇到这种情况检查一下python版本是不是3.x的。如果是，那就是版本导致的错误。卸载掉3.x安装2.7的即可解决。

python-2.7.3下载地址：

https://npm.taobao.org/mirrors/python/2.7.3/python-2.7.3.msi

另外补充一点。

node-gye还需要vc++和.netFramework4.5支持。

详细如下：

https://github.com/nodejs/node-gyp

On Windows

Option 1

Install all the required tools and configurations using Microsoft's windows-build-tools using npm install --global --production windows-build-tools from an elevated PowerShell or CMD.exe (run as Administrator).

Option 2

Install tools and configuration manually:

Visual C++ Build Environment:

Option 1: Install Visual C++ Build Tools using the Default Install option.

Option 2: Install Visual Studio 2015 (or modify an existing installation) and select Common Tools for Visual C++ during setup. This also works with the free Community and Express for Desktop editions.

:bulb: [Windows Vista / 7 only] requires .NET Framework 4.5.1
Install Python 2.7 (v3.x.x is not supported), and run npm config set python python2.7 (or see below for further instructions on specifying the proper Python version and path.)

Launch cmd, npm config set msvs_version 2015

If the above steps didn't work for you, please visit Microsoft's Node.js Guidelines for Windows for additional tips.

If you have multiple Python versions installed, you can identify which Python version node-gyp uses by setting the '--python' variable: