@tunnckocore/execa

@tunnckocore/execa

Thin layer on top of execa that allows executing multiple commands in parallel or in sequence with control for concurrency

Install

Requires Node.js v8.11+

yarn add @tunnckocore/execa

API

Generated using jest-runner-docs@v0.1.0.

.exec

Uses [execa][] v2, execa.command() method. As stated there, think of it as mix of child_process's .execFile and .spawn. It is pretty similar to the .shell method too, but only visually because it does not uses the system's shell, meaning it does not have access to the system's environment variables. You also can control concurrency by passing options.concurrency option. For example, pass concurrency: 1 to run in series instead of in parallel which is the default behavior.

Signature

function(cmds, options) 

Params

• cmds - a commands to execute in parallel or series
• options - directly passed to [execa][] and so to child_process
• returns - resolved or rejected promises

It also can accept array of multiple strings of commands that will be executed in series or in parallel (default).

Example

import { exec } from '@tunnckocore/execa';
// or
// const { exec } = require('@tunnckocore/execa');

async function main() {
  await exec('echo "hello world"', { stdio: 'inherit' });

  // executes in series (because `concurrency` option is set to `1`)
  await exec([
    'prettier-eslint --write foobar.js',
    'eslint --format codeframe foobar.js --fix'
  ], { stdio: 'inherit', preferLocal: true, concurrency: 1 });
}

main();

.shell

Similar to exec, but also can access the system's environment variables from the command.

Signature

function(cmds, options) 

Params

• cmds - a commands to execute in parallel or series
• options - directly passed to execa
• returns - resolved or rejected promises

Example

import { shell } from '@tunnckocore/execa';
// or
// const { shell } = require('@tunnckocore/execa');

async function main() {
  // executes in series
  await shell([
    'echo unicorns',
    'echo "foo-$HOME-bar"',
    'echo dragons'
  ], { stdio: 'inherit' });

  // exits with code 3
  try {
    await shell([
      'exit 3',
      'echo nah'
    ]);
  } catch (er) {
    console.error(er);
    // => {
    //  message: 'Command failed: /bin/sh -c exit 3'
    //  killed: false,
    //  code: 3,
    //  signal: null,
    //  cmd: '/bin/sh -c exit 3',
    //  stdout: '',
    //  stderr: '',
    //  timedOut: false
    // }
  }
}

main();

execa

Same as [execa][]'s default export, see its documentation. Think of this as a mix of child_process.execFile() and child_process.spawn().

Signature

function(file, args, options) 

Params

• file - executable to run
• args - arguments / flags to be passed to file
• options - optional options, passed to child_process's methods

Example

import execa from '@tunnckocore/execa'
// or
// const execa = require('@tunnckocore/execa');

async function main() {
  await execa('npm', ['install', '--save-dev', 'react'], { stdio: 'inherit' });
}

main();