NodeJS > exécuter du shell code

Possibly using commander.js to use frame your code : You could use the child_proccess module from node’s API :

 

var exec = require('child_process').exec, child;

child = exec('cat *.js bad_file | wc -l',
   function (error, stdout, stderr) {
      console.log('stdout: ' + stdout);
      console.log('stderr: ' + stderr);
      if (error !== null) {
         console.log('exec error: ' + error);
      }
   });
child();

 

Except for one thing. You’ll get the error "child is not a function". The call to exec() executes the command - no need to call child(). Unfortunately, the callback isn’t called whenever the child process has something to output - it is called only when the child process exits. Sometimes that’s OK and sometimes it’s not

 

To avoid callbacks, you can use execSync.

 

ES6 has been accepted as a standard and ES7 is around the corner so it deserves updated answer. We’ll use ES6+async/await with nodejs+babel as an example, prerequisites are:

 

nodejs with npm

 

babel

 

Your example foo.js file may look like:

 

import { exec } from 'child_process';

/**
 * Execute simple shell command (async wrapper).
 * @param {String} cmd
 * @return {Object} { stdout: String, stderr: String }
 */
async function sh(cmd) {
  return new Promise(function (resolve, reject) {
    exec(cmd, (err, stdout, stderr) => {
      if (err) {
        reject(err);
      } else {
        resolve({ stdout, stderr });
      }
    });
  });
}

async function main() {
   let { stdout } = await sh('ls');
   for (let line of stdout.split('\n')) {
      console.log(`ls: ${line}`);
   }
}

main();

 

Make sure you have babel:

 

npm i babel-cli -g

 

Install latest preset:

 

npm i babel-preset-latest

 

Run it via:

 

babel-node --presets latest foo.js

 

If you only need to execute a quick command, all the async/await is overkill. You can just use execSync

 

In a nutshell:

 

// Instantiate the Shell object and invoke its execute method.
var oShell = new ActiveXObject("Shell.Application");

var commandtoRun = "C:\\Winnt\\Notepad.exe";
if (inputparms != "") {
  var commandParms = document.Form1.filename.value;
}

// Invoke the execute method.
oShell.ShellExecute(commandtoRun, commandParms, "", "open", "1");

 

Just for info phpied.com/javascript-shell-scripting – Eduplessis Oct 21 ’15 at 1:37

 

There seems to be a lot of hand-wringing over which web browser this is running in, but folks should realize that JavaScript is also a perfectly valid Windows shell scripting language. – Craig Feb 3 ’16 at 0:48

 

With NodeJS is simple like that! And if you want to run this script at each boot of your server, you can have a look on the forever-service application!

 

var exec = require('child_process').exec;

exec('php main.php', function (error, stdOut, stdErr) {
    // do what you want!
});

 

To avoid callbacks, for quick commands you can use execSync.

 

I don’t know why the previous answers gave all sorts of complicated solutions. If you just want to execute a quick command like ls, you don’t need async/await or callbacks or anything. Here’s all you need - execSync:

 

const execSync = require('child_process').execSync;
// import { execSync } from 'child_process';  // replace ^ if using ES modules
const output = execSync('ls', { encoding: 'utf-8' });  // the default is 'buffer'
console.log('Output was:\n', output);

 

For error handling, add a try/catch block around the statement.

 

If you’re running a command that takes a long time to complete, then yes, look at the asynchronous exec function.

With nashorn you can write a script like this:

 

$EXEC('find -type f');
var files = $OUT.split('\n');
files.forEach(...
...

 

and run it:

 

jjs -scripting each_file.js

 

Here is simple command that executes ifconfig shell command of Linux

 

var process = require('child_process');
process.exec('ifconfig',function (err,stdout,stderr) {
    if (err) {
        console.log("\n"+stderr);
    } else {
        console.log(stdout);
    }
});

 

vim command.js

 

copy n past this

 

#!/usr/bin/env node
function execute(command) {
  const exec = require('child_process').exec

  exec(command, (err, stdout, stderr) => {
    process.stdout.write(stdout)
  })
}

execute('echo "Hello World!"')

 

node command.js