What is @parcel/watcher?
The @parcel/watcher package is a file system watcher that provides an efficient way to subscribe to changes in the file system. It is designed to be fast and works across multiple platforms. It can be used to watch for changes in files and directories and perform actions in response to those changes.
What are @parcel/watcher's main functionalities?
Subscribing to file changes
This feature allows you to subscribe to changes in a specific directory. The callback function is called with an array of events whenever a change occurs. Each event contains the type of change (e.g., 'create', 'update', 'delete') and the path to the affected file or directory.
const {subscribe} = require('@parcel/watcher');
async function run() {
await subscribe('/path/to/directory', (err, events) => {
if (err) {
// Handle the error
return;
}
// Handle file system change events
events.forEach(event => {
console.log(`Type: ${event.type}, Path: ${event.path}`);
});
});
}
run();
Unsubscribing from file changes
This feature allows you to unsubscribe from a previously established subscription. This is useful when you no longer need to watch for changes or when your application is shutting down.
const {subscribe, unsubscribe} = require('@parcel/watcher');
let subscription;
async function run() {
subscription = await subscribe('/path/to/directory', (err, events) => {
// Handle file system change events
});
}
async function stop() {
await unsubscribe(subscription);
}
run();
// Later on, when you want to stop watching
stop();
Other packages similar to @parcel/watcher
chokidar
Chokidar is a popular file watching package that provides a high-level API to watch file system changes. It is known for its stability and compatibility with multiple platforms. Chokidar is often used because of its extensive feature set and ease of use, but it may be slower than @parcel/watcher for large directories or projects.
watchpack
Watchpack is a wrapper around the file-watching functionality of Node.js and other file-watching libraries. It is used by webpack to detect changes in files. Watchpack offers a good balance of features and performance, but @parcel/watcher might provide better performance in certain scenarios due to its focus on speed and efficiency.
node-watch
Node-watch is a simple and lightweight file watching library. It is easy to use and works across different platforms. While it may not have as many features as @parcel/watcher, it is suitable for simpler use cases where a straightforward file watching solution is needed.