| # fsevents |
|
|
| Native access to MacOS FSEvents in [Node.js](https://nodejs.org/) |
|
|
| 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](https://github.com/paulmillr/chokidar). |
|
|
| ## Usage |
|
|
| ```sh |
| npm install fsevents |
| ``` |
|
|
| Supports only **Node.js v8.16 and higher**. |
|
|
| ```js |
| const fsevents = require('fsevents'); |
| |
| // To start observation |
| const stop = fsevents.watch(__dirname, (path, flags, id) => { |
| const info = fsevents.getInfo(path, flags); |
| }); |
| |
| // To end observation |
| stop(); |
| ``` |
|
|
| > **Important note:** The API behaviour is slightly different from typical JS APIs. The `stop` function **must** be |
| > retrieved and stored somewhere, even if you don't plan to stop the watcher. If you forget it, the garbage collector |
| > will eventually kick in, the watcher will be unregistered, and your callbacks won't be called anymore. |
|
|
| 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 changed |
| * `flags: number` - a numeric value describing what the change was |
| * `id: 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: |
|
|
| ```js |
| /** |
| * @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 |
| } |
| ``` |
|
|
| ## Changelog |
|
|
| - v2.3 supports Apple Silicon ARM CPUs |
| - v2 supports node 8.16+ and reduces package size massively |
| - v1.2.8 supports node 6+ |
| - v1.2.7 supports node 4+ |
|
|
| ## Troubleshooting |
|
|
| - I'm getting `EBADPLATFORM` `Unsupported platform for fsevents` error. |
| - 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](https://github.com/fsevents/fsevents) and [NPM Page](https://npmjs.org/package/fsevents) |
|
|
