摘要：直接全局安裝是會出現錯誤錯誤如下這種錯誤提示是你沒有權限將安裝文件直接寫入一個權限控制文件里。

直接 npm install -g @vue/cli全局安裝是會出現錯誤

錯誤如下:

Last login: Tue Oct 30 23:43:58 on ttys000
asusdeMac:~ asus$ npm install -g @vue/cli
npm WARN deprecated cross-spawn-async@2.2.5: cross-spawn no longer requires a build toolchain, use it instead
npm WARN checkPermissions Missing write access to /usr/local/lib/node_modules
npm WARN apollo-link-persisted-queries@0.2.1 requires a peer of graphql@^0.11.0 || ^0.12.0 || ^0.13.0 but none is installed. You must install peer dependencies yourself.
npm WARN graphql-subscriptions@0.5.8 requires a peer of graphql@^0.10.5 || ^0.11.3 || ^0.12.0 || ^0.13.0 but none is installed. You must install peer dependencies yourself.
npm WARN @apollographql/apollo-upload-server@5.0.3 requires a peer of graphql@^0.13.1 but none is installed. You must install peer dependencies yourself.
npm WARN graphql-tools@3.1.1 requires a peer of graphql@^0.13.0 but none is installed. You must install peer dependencies yourself.
npm WARN graphql-subscriptions@0.5.8 requires a peer of graphql@^0.10.5 || ^0.11.3 || ^0.12.0 || ^0.13.0 but none is installed. You must install peer dependencies yourself.

npm ERR! path /usr/local/lib/node_modules
npm ERR! code EACCES
npm ERR! errno -13
npm ERR! syscall access
npm ERR! Error: EACCES: permission denied, access "/usr/local/lib/node_modules"
npm ERR!  { Error: EACCES: permission denied, access "/usr/local/lib/node_modules"
npm ERR!   stack: "Error: EACCES: permission denied, access "/usr/local/lib/node_modules"",
npm ERR!   errno: -13,
npm ERR!   code: "EACCES",
npm ERR!   syscall: "access",
npm ERR!   path: "/usr/local/lib/node_modules" }
npm ERR! 
npm ERR! The operation was rejected by your operating system.
npm ERR! It is likely you do not have the permissions to access this file as the current user
npm ERR! 
npm ERR! If you believe this might be a permissions issue, please double-check the
npm ERR! permissions of the file and its containing directories, or try running
npm ERR! the command again as root/Administrator (though this is not recommended).

npm ERR! A complete log of this run can be found in:
npm ERR!     /Users/asus/.npm/_logs/2018-10-31T06_48_54_915Z-debug.log

這種錯誤提示是你沒有權限將安裝文件直接寫入一個權限控制文件里。

npm全局安裝文件時可以使用 ‘sudo’ 任何管理員賬戶都可以使用sudo來獲取 root 權限。

使用 sudo npm install -g @vue/cli 進行安裝

1、輸入安裝命令后，命令提醒你輸入Password密碼，目的使用管理員權限去安裝

Last login: Tue Oct 30 23:44:47 on ttys000
asusdeMac:~ asus$ sudo npm install -g @vue/cli

We trust you have received the usual lecture from the local System
Administrator. It usually boils down to these three things:

    #1) Respect the privacy of others.
    #2) Think before you type.
    #3) With great power comes great responsibility.

Password:

密碼輸入完后稍等一會兒就安裝成功啦！

asusdeMac:~ asus$ sudo npm install -g @vue/cli
npm WARN deprecated cross-spawn-async@2.2.5: cross-spawn no longer requires a build toolchain, use it instead
/usr/local/bin/vue -> /usr/local/lib/node_modules/@vue/cli/bin/vue.js

> fsevents@1.2.4 install /usr/local/lib/node_modules/@vue/cli/node_modules/fsevents
> node install

[fsevents] Success: "/usr/local/lib/node_modules/@vue/cli/node_modules/fsevents/lib/binding/Release/node-v57-darwin-x64/fse.node" already installed
Pass --update-binary to reinstall or --build-from-source to recompile

> protobufjs@6.8.8 postinstall /usr/local/lib/node_modules/@vue/cli/node_modules/protobufjs
> node scripts/postinstall


> nodemon@1.18.5 postinstall /usr/local/lib/node_modules/@vue/cli/node_modules/nodemon
> node bin/postinstall || exit 0

Love nodemon? You can now support the project via the open collective:
 > https://opencollective.com/nodemon/donate

npm WARN graphql-subscriptions@0.5.8 requires a peer of graphql@^0.10.5 || ^0.11.3 || ^0.12.0 || ^0.13.0 but none is installed. You must install peer dependencies yourself.
npm WARN apollo-link-persisted-queries@0.2.1 requires a peer of graphql@^0.11.0 || ^0.12.0 || ^0.13.0 but none is installed. You must install peer dependencies yourself.
npm WARN graphql-subscriptions@0.5.8 requires a peer of graphql@^0.10.5 || ^0.11.3 || ^0.12.0 || ^0.13.0 but none is installed. You must install peer dependencies yourself.
npm WARN @apollographql/apollo-upload-server@5.0.3 requires a peer of graphql@^0.13.1 but none is installed. You must install peer dependencies yourself.
npm WARN graphql-tools@3.1.1 requires a peer of graphql@^0.13.0 but none is installed. You must install peer dependencies yourself.

+ @vue/cli@3.0.5
added 730 packages from 514 contributors in 167.036s

檢測是否在全局安裝成功 輸入命令 vue -v

asusdeMac:~ asus$ vue -v
Usage: vue  [options]

Options:
  -V, --version                         output the version number
  -h, --help                            output usage information

Commands:
  create [options]            create a new project powered by vue-cli-service
  add  [pluginOptions]          install a plugin and invoke its generator in an already created project
  invoke  [pluginOptions]       invoke the generator of a plugin in an already created project
  inspect [options] [paths...]          inspect the webpack config in a project with vue-cli-service
  serve [options] [entry]               serve a .js or .vue file in development mode with zero config
  build [options] [entry]               build a .js or .vue file in production mode with zero config
  ui [options]                          start and open the vue-cli ui
  init [options]