Webpack Synchronizable Shell Plugin

0.0.7 verified Sat Apr 25 auth: no javascript

A webpack plugin that runs shell commands before, after, or on exit of the build process, forked from webpack-shell-plugin. Version 0.0.7 (2018) is the latest stable release; no updates since. Unlike alternatives, it provides fine-grained control over script execution order with blocking and parallel options per lifecycle hook (onBuildStart, onBuildEnd, onBuildExit). Suitable for tasks like linting, testing, or deployment scripts. Note: development seems abandoned; last commit 2018.

Common errors

error TypeError: Cannot read property 'scripts' of undefined ↓

cause Passing scripts directly to plugin constructor instead of inside an object under onBuildStart/onBuildEnd/onBuildExit.

fix

Wrap scripts array inside an object, e.g., onBuildStart: { scripts: ['...'], blocking: false, parallel: false }

error Error: spawn ENOENT ↓

cause Shell command not found or safe:false default (uses spawn) fails on some systems.

fix

Set safe:true to use exec instead of spawn, or provide full path to command.

Warnings

gotcha Combining blocking:true with parallel:true is not supported; behavior undefined. ↓

fix Set at most one to true; if both needed, use sequential scripts or separate hooks.

breaking API differs from webpack-shell-plugin; direct scripts array is not accepted. ↓

fix Wrap scripts in onBuildStart/onBuildEnd/onBuildExit objects.

deprecated Option 'verbose' is deprecated and has no effect. ↓

fix Remove 'verbose' from configuration.

gotcha onBuildExit fires during watch mode after each compilation; not just on process exit. ↓

fix Use onBuildEnd for post-compilation tasks if you want to avoid repeated exit hooks.

Install

npm install webpack-synchronizable-shell-plugin

yarn add webpack-synchronizable-shell-plugin

pnpm add webpack-synchronizable-shell-plugin

Imports

WebpackSynchronizableShellPlugin

wrong

import WebpackSynchronizableShellPlugin from 'webpack-synchronizable-shell-plugin';

correct

const WebpackSynchronizableShellPlugin = require('webpack-synchronizable-shell-plugin');

Package does not provide ES modules; must use require() in webpack.config.js.

new WebpackSynchronizableShellPlugin({...})

wrong

new WebpackSynchronizableShellPlugin({ scripts: ['echo start'] })

correct

new WebpackSynchronizableShellPlugin({ onBuildStart: { scripts: ['echo start'], blocking: true } })

Plain object with scripts array is not accepted; must use lifecycle hooks like onBuildStart.

configuration structure
wrong
```
onBuildStart: []  // directly passing array
```
correct
```
onBuildStart: { scripts: [], blocking: false, parallel: false }
```
Each lifecycle hook expects an object with scripts, blocking, parallel properties.

Quickstart

Shows typical setup with three lifecycle hooks, blocking/parallel options, and plugin instantiation in webpack config.

const WebpackSynchronizableShellPlugin = require('webpack-synchronizable-shell-plugin');

module.exports = {
  entry: './src/index.js',
  output: { path: __dirname + '/dist', filename: 'bundle.js' },
  plugins: [
    new WebpackSynchronizableShellPlugin({
      onBuildStart: {
        scripts: ['echo "Build starting..."'],
        blocking: true,
        parallel: false
      },
      onBuildEnd: {
        scripts: ['echo "Build complete"'],
        blocking: false,
        parallel: true
      },
      onBuildExit: {
        scripts: ['echo "Done"'],
        blocking: false,
        parallel: false
      },
      dev: true,
      safe: false
    })
  ]
};