JarCastingfsevents 
Native access to MacOS FSEvents in Node.js
The FSEvents API in MacOS allows applications to register for notifications of changes to a given directory tree. It is a very fast and lightweight alternative to kqueue.
This is a low-level library. For a cross-platform file watching module that uses fsevents, check out Chokidar.
Installation
Supports only Node.js v8.16 and higher.
npm install fsevents
Usage
const fsevents = require('fsevents');
const stop = fsevents.watch(__dirname, (path, flags, id) => {
const info = fsevents.getInfo(path, flags, id);
}); // To start observation
stop(); // To end observation
The callback passed as the second parameter to .watch get's called whenever the operating system detects a a change in the file system. It takes three arguments:
fsevents.watch(dirname: string, (path: string, flags: number, id: string) => void): () => Promise<undefined>
path: string- the item in the filesystem that have been changedflags: number- a numeric value describing what the change wasid: string- an unique-id identifying this specific event
Returns closer callback which when called returns a Promise resolving when the watcher process has been shut down.
fsevents.getInfo(path: string, flags: number, id: string): FsEventInfo
The getInfo function takes the path, flags and id arguments and converts those parameters into a structure that is easier to digest to determine what the change was.
The FsEventsInfo has the following shape:
/**
* @typedef {'created'|'modified'|'deleted'|'moved'|'root-changed'|'cloned'|'unknown'} FsEventsEvent
* @typedef {'file'|'directory'|'symlink'} FsEventsType
*/
{
"event": "created", // {FsEventsEvent}
"path": "file.txt",
"type": "file", // {FsEventsType}
"changes": {
"inode": true, // Had iNode Meta-Information changed
"finder": false, // Had Finder Meta-Data changed
"access": false, // Had access permissions changed
"xattrs": false // Had xAttributes changed
},
"flags": 0x100000000
}
Engine compatibility
- v2 supports node 8.16+
- v1.2.8 supports node 6+
- v1.2.7 supports node 4+
Troubleshooting
- I'm getting
EBADPLATFORMUnsupported platform for fseventserror. - It's fine, nothing is broken. fsevents is macos-only. Other platforms are skipped. If you want to hide this warning, report a bug to NPM bugtracker asking them to hide ebadplatform warnings by default.
License
The MIT License Copyright (C) 2010-2020 by Philipp Dunkel, Ben Noordhuis, Elan Shankar, Paul Miller — see LICENSE file.
Visit our GitHub page and NPM Page
