shell.exec bug

[xgqfrms]

shell.exec bug

shell.exec not work

shelljs/shelljs#1048

Node version

v12.18.0

ShellJS version

  "dependencies": {
    "shelljs": "^0.8.4"
  }

Operating system:

macOS 10.15.7

Description of the bug:

wanted

$ ./spe.js  PORT_ENV=666 && node ./test.js
# ✅
# test command = export PORT_ENV=666
# PORT_ENV = 666
# PORT_ENV =  666

actually

$ ./spe.js  PORT_ENV=666 && node ./test.js
# ❌
# test command = export PORT_ENV=666
# PORT_ENV = undefined
# PORT_ENV = undefined

Example ShellJS command to reproduce the error:

spe.js

#!/usr/bin/env node

/**
 *
 * @author xgqfrms
 * @license MIT
 * @copyright xgqfrms 2021.10.14
 *
 * @description Pset-process-env
 *
 */

 const shell = require("shelljs");

const fs = require("fs");

const {
  version,
  argv,
  platform,
} = process;

const isMac = (platform === 'darwin');

const args = argv.slice(2) || [];

const isPureNumber = (str = '') => {
  const numberDict = [...''.padEnd(10, 'x')].map((item, i) => `${i}`);
  const arr = `${str}`.split('');
  return arr.every(item => numberDict.includes(item));
}

let key = "";
let env = "";
if (!args[0]) {
  args[0] = "";
  key = 'PORT_ENV';
  env = 8080;
} else {
  const tempArr = args[0].split('=');
  key = tempArr[0] || 'PORT_ENV';
  env = isPureNumber(tempArr[1]) ? parseInt(tempArr[1]) : tempArr[1];
}

let command = ``;

  if(isMac) {
    command = `export ${key}=${env}`;
  } else {
    command = `set ${key}=${env}`;
  }


shell.exec(command);

console.log('\n test command =', command);
console.log('\n PORT_ENV =', process.env.PORT_ENV);

test.js

// console.log('process.env =', process.env);
console.log('PORT_ENV =', process.env.PORT_ENV);

[xgqfrms]

shell.exec run export not work

#!/usr/bin/env node

const shell = require("shelljs");

const key = 'PORT_ENV';
const env = 8888;

// const command = `export ${key}=${env}`;
// const command = `set ${key}=${env}`;

const command = 'export PORT_ENV=8888';

// shelljs 执行 command

shell.exec('whoami');
shell.exec('which sh');
shell.exec('which bash');
// shell.exec('pwd');
// shell.exec('ls -al');
shell.exec(command);

console.log('\n command =', command);
console.log('\n PORT_ENV =', process.env.PORT_ENV);

[xgqfrms]

$ spe PORT_ENV=666 && node ./test.js

# ❌
$ spe PORT_ENV=666 && node -e "console.log('PORT_ENV =', process.env.PORT_ENV);"

$ node ./spe-bug.js

# ✅
$ export PORT_ENV=8090 && node -e "console.log('PORT_ENV =', process.env.PORT_ENV);"

[xgqfrms]

shelljs exec 无效

https://segmentfault.com/q/1010000015601889

https://www.ruanyifeng.com/blog/2015/05/command-line-with-node.html

[xgqfrms]

process bug ???

1. parent process => child process ✅ 可以继承 enV
2. child process => parent process ❌ 无法改变 env

If you are the child process (the process that got execed), you can not set the environment variable of your parent process.

https://stackoverflow.com/questions/49372501/set-environment-variable-with-shelljs
https://www.coder.work/article/1378443

在所有 UNIX 和 类Unix系统中, 每个进程都有其各自的环境变量设置。 缺省情况下, 当一个进程被创建时， 除了创建过程中的明确更改外，它继承了其父进程的绝大部分环境设置。

https://en.wikipedia.org/wiki/Environment_variable

// shell.exec(command);

if(isMac) {
  // command = `export ${key}=${env}`;
  // shell.exec(command);
  // shell.env[`"${key}"`] = env;
} else {
  // command = `set ${key}=${env}`;
  // shell.exec(command);
  // shell.env[`"${key}"`] = env;
}

// shell.env['"' + key + '"'] = env;
// shell.env[`"${key}"`] = env;
shell.env[key] = env;

console.log('\n🎉 finished!');

不同的 node.js child process env

/*
// 不同的 node.js child process env bug ???

spe PORT_ENV=8090 && node ./bug.js

spe PORT_ENV=8090 && node -e "console.log('PORT_ENV =', process.env.PORT_ENV);"

*/

[xgqfrms]

Linux 权限管理

https://www.imooc.com/search/?type=course&words=Linux

https://www.imooc.com/learn/481

shell 正则表达式

https://www.imooc.com/learn/378

shell 编程之条件判断与流程控制

https://www.imooc.com/learn/408

《Tony老师聊shell》

https://www.imooc.com/u/279399/courses?sort=publish

[xgqfrms]

shell编程之环境变量配置文件 ✅

https://www.imooc.com/learn/361

shell编程之变量 ✅

https://www.imooc.com/learn/336

[xgqfrms]

兄弟连最新版 Linux 视频教程

沈超 === Tony

https://www.bilibili.com/video/BV1He41147d6/

https://www.bilibili.com/video/BV1mW411i7Qf

https://www.lampbrother.net/linux

https://www.itxdl.com/linux

[xgqfrms]

兄弟连-沈超

云计算教学总监，国内著名的 Linux 技术专家，十余年 Linux 从业经验，培训学员过万名，录制的 Linux 教学视频过百万次下载，曾获微软认证、红帽认证讲师、北京市优秀园丁奖…历任即时科研集团项目经理、光宇华夏游戏运维部高级工程师，负责百万级同时在线大型网络游戏：希望Online、问道的维护与运维工作。

https://ke.qq.com/teacher/57362523

https://www.imooc.com/qadetail/245958?t=561731#id_561731

必须是，听声音也听出来了；

再看一下，讲课内容和风格，100% 了；

imooc的Tony老师 === 兄弟连的沈超老师

https://www.cnblogs.com/yongestcat/p/11736732.html

https://zhuanlan.zhihu.com/p/345035621

https://www.icourse163.org/course/itxdl-1002597008

兄弟连教育成立于2006年，专注于软件开发技术培训，是PHP/LAMP技术培训学校，主营业务包括PHP培训、Java培训、安卓培训、软件开发、人才输出、教材出版、企业培训等。总部设在北京，在上海、广州、深圳、沈阳、石家庄、西安、武汉等城市都设有教学中心。

李超在信中表示，因公司现金流问题，即日起兄弟连北京校区停止招生，同时员工全部遣散。上海、广州校区已相继经独立运营，不再归属集团总部，可更换品牌正常开展业务。沈阳、西安校区业务、院校合作业务，相关负责人带领员工根据自身情况更换品牌可选择自行创业，自负盈亏。

其实，早在2019年底，兄弟连的资金状况就已经发生问题，最后的孤注一掷在学生寒假的线下营收上，可是此次疫情猛烈，政府通知线下培训业务暂停，成为压倒兄弟连的最后一根稻草。

“死撑不下去了”，李超在信中写明了疫情发生后的机构处境，“这对资金储备少，包袱重、一直亏损的兄弟连无疑是雪上加霜。节前咱们勒紧腰带，缓发工资、全体动员，压缩成本，就是为了节后招生旺季打个翻身仗。哪知这次疫情来的如此凶猛、猝不及防，把我们的计划全部打乱。”

[xgqfrms]

shelljs export bug

shelljs/shelljs#980

$ shell.echo(shell.env.PATH);

shelljs/shelljs#815 (comment)

[xgqfrms]

    "scripts": {
        "dev": "cross-env NODE_OPTIONS='--max-old-space-size=8192' && npm run old_dev",
        "old_dev": "cross-env NODE_ENV=development webpack-dev-server --inline",
        "build": "rimraf dist && cross-env NODE_ENV=production webpack --progress --hide-modules",
        "eslint": "eslint --fix --ext js,vue src",
        "precommit": "lint-staged"
    },

NODE_OPTIONS

https://nodejs.org/api/cli.html

https://nodejs.org/api/cli.html#cli_node_options_options

http://nodejs.cn/api/cli/node_options_options.html

[xgqfrms]

node js get system environment variable

https://stackoverflow.com/questions/4870328/read-environment-variables-in-node-js

process.env === process + env

https://nodejs.org/api/process.html#process_process_env

$ node -e 'process.env.foo = "bar"' && echo $foo

https://nodejs.dev/learn/how-to-read-environment-variables-from-nodejs

??? echo quickly blink bug ???

echo 一闪就消失了 ？？？

linux echo 一闪就消失了

http://www.bathome.net/thread-13418-1-1.html

批处理命令窗口闪一下就没了的原因：
1.如果没在行末加 pause，批处理默认以cmd /c的形式运行（运行完代码后不保存窗口——和其对应的是cmd /k命令），所以就会一闪就没了。
2.语法出错也会造成窗口一闪消失。

http://bbs.chinaunix.net/thread-1282392-1-1.html

不是看不见，是一闪而过

echo $foo;read a

[xgqfrms]

Linux Shell 脚本如何执行完毕之后不自动关闭窗口

写给前端的 shell 脚本编程详解

https://segmentfault.com/a/1190000037797344

https://developer.huawei.com/consumer/cn/forum/topic/0204414228553730437

[xgqfrms]

cross-env usage bug

单个 process 直接执行 ✅

    "scripts": {
        "dev": "cross-env NODE_OPTIONS='--max-old-space-size=8192' cross-env NODE_ENV=development webpack-dev-server --inline",
        "build": "rimraf dist && cross-env NODE_ENV=production webpack --progress --hide-modules",
        "eslint": "eslint --fix --ext js,vue src",
        "precommit": "lint-staged"
    },

cross-env NODE_OPTIONS='--max-old-space-size=8192' ❌

&& 多个 process ❌ env 不会生效

    "scripts": {
        "dev": "cross-env NODE_OPTIONS='--max-old-space-size=8192' && cross-env NODE_ENV=development webpack-dev-server --inline",
        "build": "rimraf dist && cross-env NODE_ENV=production webpack --progress --hide-modules",
        "eslint": "eslint --fix --ext js,vue src",
        "precommit": "lint-staged"
    },

  // 单个 process 直接执行 ✅
  command = `./node_modules/cross-env/dist/bin/cross-env.js ${key}='${env}' npm run dev`;
  // command = `./node_modules/cross-env/dist/bin/cross-env.js ${key}='${env}' yarn dev`;
  // && 多个 process ❌
  // command = `./node_modules/cross-env/dist/bin/cross-env.js ${key}='${env}' && npm run dev`;
  // command = `./node_modules/cross-env/dist/bin/cross-env.js ${key}='${env}' && yarn dev`;

[xgqfrms]

The Difference Between #!/bin/bash and #!/usr/bin/env bash

The Difference Between #!/usr/bin/bash and #!/usr/bin/env bash

https://www.baeldung.com/linux/bash-shebang-lines

https://stackoverflow.com/questions/16365130/what-is-the-difference-between-usr-bin-env-bash-and-usr-bin-bash

https://unix.stackexchange.com/questions/29608/why-is-it-better-to-use-usr-bin-env-name-instead-of-path-to-name-as-my