command-exists

What is command-exists?

The command-exists npm package is used to check if a given command is available in the system's PATH. It is useful for Node.js applications that need to ensure certain commands are installed before attempting to execute them.

What are command-exists's main functionalities?

Synchronous check

This feature allows you to synchronously check if a command exists in the system's PATH.

const commandExistsSync = require('command-exists').sync;

if (commandExistsSync('git')) {
  console.log('Git exists!');
} else {
  console.log('Git does not exist.');
}

Asynchronous check

This feature allows you to asynchronously check if a command exists in the system's PATH.

const commandExists = require('command-exists');

commandExists('git', function(err, commandExists) {
  if(commandExists) {
    console.log('Git exists!');
  } else {
    console.log('Git does not exist.');
  }
});

Promise-based check

This feature provides a promise-based interface to check if a command exists, which can be used with modern async/await syntax.

const commandExists = require('command-exists');

commandExists('git')
  .then(function(command) {
    console.log('Git exists!');
  }).catch(function() {
    console.log('Git does not exist.');
  });

Other packages similar to command-exists

which

The 'which' package is similar to 'command-exists' as it checks for the existence of a command. It is a Node.js implementation of the Unix 'which' command. It differs in that it provides the path to the executable if it exists, rather than just a boolean indicating existence.

lookpath

The 'lookpath' package is another alternative that checks if a command exists in the system's PATH. It is similar to 'command-exists' but returns the full path of the command if it exists. It also supports Windows and is designed to be a lightweight solution.

shelljs

While 'shelljs' is a more comprehensive shell scripting utility library, it includes a 'which' method that can be used to check for the existence of commands, similar to 'command-exists'. It provides additional shell-related functionalities beyond command checking.

README

command-exists

node module to check if a command-line command exists

installation

npm install command-exists

usage

async

var commandExists = require('command-exists');

commandExists('ls', function(err, commandExists) {

    if(commandExists) {
        // proceed confidently knowing this command is available
    }

});

promise

var commandExists = require('command-exists');

// invoked without a callback, it returns a promise
commandExists('ls')
.then(function(command){
    // proceed
}).catch(function(){
    // command doesn't exist
});

sync

var commandExistsSync = require('command-exists').sync;
// returns true/false; doesn't throw
if (commandExistsSync('ls')) {
    // proceed
} else {
    // ...
}

changelog

v1.2.7

Removes unnecessary printed output on windows.

v1.2.6

Small bugfixes.

v1.2.5

Fix windows bug introduced in 1.2.4.

v1.2.4

Fix potential security issue.

v1.2.0

Add support for promises

v1.1.0

Add synchronous version

v1.0.2

Support for windows