exec-sh

What is exec-sh?

The exec-sh npm package is a simple utility for executing shell commands in Node.js. It provides a straightforward API to run shell commands synchronously or asynchronously, with options to handle output and errors.

What are exec-sh's main functionalities?

Execute a command asynchronously

This feature allows you to execute a shell command asynchronously. The callback function handles any errors and provides the exit code if the command fails.

const execSh = require('exec-sh');
execSh('echo Hello World', function(err){
  if (err) {
    console.log('Exit code:', err.code);
    return;
  }
  console.log('Command executed successfully');
});

Execute a command synchronously

This feature allows you to execute a shell command synchronously. If the command fails, an error is thrown, and you can catch it to handle the exit code.

const execSh = require('exec-sh');
try {
  execSh.sync('echo Hello World');
  console.log('Command executed successfully');
} catch (err) {
  console.log('Exit code:', err.code);
}

Capture command output

This feature allows you to capture the standard output and standard error of the executed command. The callback function provides the stdout and stderr as arguments.

const execSh = require('exec-sh');
execSh('echo Hello World', true, function(err, stdout, stderr){
  if (err) {
    console.log('Exit code:', err.code);
    return;
  }
  console.log('stdout:', stdout);
  console.log('stderr:', stderr);
});

Other packages similar to exec-sh

child_process

The child_process module is a built-in Node.js module that provides the ability to spawn child processes. It offers more control and flexibility compared to exec-sh, including options to spawn, fork, exec, and execFile processes.

shelljs

ShellJS is a portable (Windows/Linux/macOS) implementation of Unix shell commands on top of Node.js. It provides a more extensive set of shell commands and utilities compared to exec-sh, making it suitable for more complex scripting tasks.

execa

Execa is a modern alternative to child_process. It provides a simpler and more powerful API for executing shell commands, with better support for promises and improved error handling. It is more feature-rich compared to exec-sh.

README

exec-sh

Execute shell command forwarding all stdio streams.

Features

exec-sh is a wrapper for child_process.spawn with some improvements:

• Cross platform command execution:
  • Windows: cmd /C COMMAND
  • others: sh -c COMMAND
• Fowrards all stdio streams to current terminal (by default):
  • execSh("bash")
  • execsh("echo -n Say: && read i && echo Said:$i")
• stdout and stderr are passed to callback when available
  • execSh("pwd", console.log)

Showcase

// JavaScript

execSh("echo hello exec-sh && bash", { cwd: "/home" }, function(err){
  if (err) {
    console.log("Exit code: ", err.code);
  }
});

# Terminal output: interactive bash session

hello exec-sh
bash-3.2$ pwd
/home
bash-3.2$ exit 99
exit
Exit code:  99

Usage

const execSh = require("../");

// run interactive bash shell
execSh("echo lorem && bash", { cwd: "/home" }, (err) => {
  if (err) {
    console.log("Exit code: ", err.code);
    return;
  }

  // collect streams output
  const child = execSh(["bash -c id", "echo lorem >&2"], true,
    (err, stdout, stderr) => {
      console.log("error: ", err);
      console.log("stdout: ", stdout);
      console.log("stderr: ", stderr);
    });
});

Promise Interface

const execShPromise = require("exec-sh").promise;

// run interactive bash shell
const run = async () => {
  let out;

  try {
    out = await execShPromise('pwd', true);
  } catch (e) {
    console.log('Error: ', e);
    console.log('Stderr: ', e.stderr);
    console.log('Stdout: ', e.stdout);

    return e;
  }

  console.log('out: ', out.stdout, out.stderr);
}

run();

Public API

execSh(command, [options], [callback])

Execute shell command forwarding all stdio.

Parameters:

• command {String|Array} - The command to run, or array of commands
• [options] {Object|TRUE} - Options object passed directly to child_process.spawn, when TRUE then { stdio: null } used
• [callback] {Function} - callback(err, stdout, stderr)
• err {Error|NULL} - Error object. Has code property containing last command exit code when available
• stdout {String|NULL} - aggregated stdout or NULL if not available
• stderr {String|NULL} - aggregated stderr or NULL if not available

Return Values:

Returns ChildProcess object.

Private API

Complete API Documentation including private and public methods is generated from source code by JSDoc tool and is available here.

Code Coverage

Code coverage report for all files is available here.

Scripts

• npm test - run tests
• npm run jsdoc - build jsdoc
• npm run dev - run tests continuously

License

The MIT License (MIT)