watchpack

What is watchpack?

The watchpack npm package is a wrapper around the file-watching functionality of Node.js and chokidar. It provides a higher-level API for watching file changes in a specified directory or set of directories. It is often used in build tools and development servers to watch for file changes and trigger rebuilds or reloads.

What are watchpack's main functionalities?

Watching Files and Directories

This feature allows you to watch for changes in specific files and directories. You can listen for 'change' events on individual files and 'aggregated' events for batch changes.

const Watchpack = require('watchpack');

const wp = new Watchpack({
  // options
});

wp.watch({
  files: ['file1.js', 'file2.js'],
  directories: ['dir1', 'dir2'],
  missing: ['file3.js', 'file4.js']
});

wp.on('change', (filePath, mtime, explanation) => {
  console.log(`${filePath} changed`, mtime, explanation);
});

wp.on('aggregated', (changes, removals) => {
  console.log('Changes:', changes);
  console.log('Removals:', removals);
});

Pausing and Resuming Watch

This feature allows you to temporarily pause the watching process and resume it later. This can be useful when performing batch operations that should not trigger watch events.

const wp = new Watchpack({});

// Start watching
wp.watch({ files: ['file1.js'] });

// Pause watching
wp.pause();

// After some time, resume watching
wp.watch({ files: ['file1.js'] });

Getting Watched Items

This feature allows you to retrieve a list of all files that are currently being watched. This can be useful for debugging or logging purposes.

const wp = new Watchpack({});

wp.watch({ files: ['file1.js'] });

const watchedFiles = wp.getWatchedFiles();
console.log(watchedFiles); // Outputs: ['file1.js']

Other packages similar to watchpack

chokidar

Chokidar is a more low-level file watching library that watchpack uses under the hood. It provides more granular control over file watching and events but requires more setup and configuration compared to watchpack.

gaze

Gaze is another file watching library that offers similar functionality to watchpack. It allows you to watch files and directories for changes and supports patterns for file matching. It differs in its API and the way it handles events and patterns.

nodemon

Nodemon is a tool that helps develop node.js based applications by automatically restarting the node application when file changes in the directory are detected. While it also watches files for changes, its primary use case is different as it focuses on restarting applications rather than providing an API for developers to hook into file changes.