关于设置python路径的npm安装错误

Question

PS C:\Users\Concierge\downloads\prod\pdf2\ipfs_image_uploader> npm start

> react-box@0.1.0 start C:\Users\Concierge\downloads\prod\pdf2\ipfs_image_uploader
> node scripts/start.js

internal/modules/cjs/loader.js:582
    throw err;
    ^

Error: Cannot find module 'dotenv'
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:580:15)
    at Function.Module._load (internal/modules/cjs/loader.js:506:25)
    at Module.require (internal/modules/cjs/loader.js:636:17)
    at require (internal/modules/cjs/helpers.js:20:18)
    at Object.<anonymous> (C:\Users\Concierge\downloads\prod\pdf2\ipfs_image_uploader\scripts\
    at Module._compile (internal/modules/cjs/loader.js:688:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:699:10)
    at Module.load (internal/modules/cjs/loader.js:598:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:537:12)
    at Function.Module._load (internal/modules/cjs/loader.js:529:3)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! react-box@0.1.0 start: `node scripts/start.js`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the react-box@0.1.0 start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output ab
npm WARN Local package.json exists, but node_modules missing, did you mean to install?

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\Concierge\AppData\Roaming\npm-cache\_logs\2018-11-17T04_27_59_461Z-debug
PS C:\Users\Concierge\downloads\prod\pdf2\ipfs_image_uploader>

当我运行命令npm install时，会出现以下错误：

> scrypt@6.0.3 preinstall /Users/user/Documents/pdfuploader/node_modules/scrypt
> node node-scrypt-preinstall.js
> scrypt@6.0.3 install /Users/user/Documents/pdfuploader/node_modules/scrypt
> node-gyp rebuild

gyp ERR! configure error 
gyp ERR! stack Error: Can't find Python executable "/path/to/executable/python2.7", you can set the PYTHON env variable.
gyp ERR! stack     at PythonFinder.failNoPython (/usr/local/lib/node_modules/npm/node_modules/node-gyp/lib/configure.js:484:19)
gyp ERR! stack     at PythonFinder.<anonymous> (/usr/local/lib/node_modules/npm/node_modules/node-gyp/lib/configure.js:406:16)
gyp ERR! stack     at F (/usr/local/lib/node_modules/npm/node_modules/which/which.js:68:16)
gyp ERR! stack     at E (/usr/local/lib/node_modules/npm/node_modules/which/which.js:80:29)
gyp ERR! stack     at /usr/local/lib/node_modules/npm/node_modules/which/which.js:89:16
gyp ERR! stack     at /usr/local/lib/node_modules/npm/node_modules/isexe/index.js:42:5
gyp ERR! stack     at /usr/local/lib/node_modules/npm/node_modules/isexe/mode.js:8:5
gyp ERR! stack     at FSReqWrap.oncomplete (fs.js:152:21)
gyp ERR! System Darwin 17.5.0
gyp ERR! command "/usr/local/bin/node" "/usr/local/lib/node_modules/npm/node_modules/node-gyp/bin/node-gyp.js" "rebuild"
gyp ERR! cwd /Users/user/Documents/pdfuploader/node_modules/scrypt
gyp ERR! node -v v8.12.0
gyp ERR! node-gyp -v v3.8.0
gyp ERR! not ok 
npm WARN ajv-keywords@3.2.0 requires a peer of ajv@^6.0.0 but none is installed. You must install peer dependencies yourself.

npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! scrypt@6.0.3 install: `node-gyp rebuild`
npm ERR! Exit status 1
npm ERR! 
npm ERR! Failed at the scrypt@6.0.3 install script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     /Users/user/.npm/_logs/2018-11-18T05_45_00_864Z-debug.log`

我尝试像下面这样设置pythonpath:https://www.tutorialspoint.com/how-to-set-your-python-path-on-Mac，但没有帮助

我只是通过使用本教程插入路径/library/frameworks/python.framework/versions/2.7/lib/python2.7/site-packages:https://www.howtogeek.com/118594/how-to-edit-your-system-path-for-easy-command-line-access/来对其进行分类

但是，当npm运行开始时，我又得到了一个错误:`users-air:pdfuploader user$npm运行开始

客户端@0.1.0 start/users/user/documents/pdfuploader react-scripts start

找不到所需的文件。名称：index.html搜索：/users/user/documents/pdfuploader/public npm错误！代码ELIFECYCLE npm错误！错误1 npm错误！客户端@0.1.0 start:react-scripts startnpm错误！退出状态1 npm错误！npm错误！在客户端@0.1.0启动脚本失败。npm错误！这可能不是NPM的问题。上面可能有额外的日志记录输出。

Answer 1

一些nodeJS模块是用C++编写的，安装时需要编译。这个过程需要安装python2。现在，大多数Mac实际上默认安装了python2，但“Python”可能还不在您的可执行文件路径上。

在Mac上，python应用程序通常位于/system/library/frameworks/python.framework/versions/2.7/bin/python2.7。如果/system/library/frameworks/中没有'python.framework'文件夹，则需要安装Python。如果存在，那么只需在/usr/bin中对前面提到的Python2.7可执行文件进行符号链接。另外，通过在终端上键入echo$path，确保/usr/bin存在于可执行路径上。

若要创建符号链接，请运行：