A globbing fs.watch wrapper built from the best parts of other fine watch libs.
Compatible with Node.js 0.10/0.8, Windows, OSX and Linux.

Install the module with: npm install gaze or place into your package.json and run npm install.

var gaze = require('gaze');

// Watch all .js files/dirs in process.cwd()
gaze('**/*.js', function(err, watcher) {
  // Files have all started watching
  // watcher === this

  // Get all watched files
  console.log(this.watched());

  // On file changed
  this.on('changed', function(filepath) {
    console.log(filepath + ' was changed');
  });

  // On file added
  this.on('added', function(filepath) {
    console.log(filepath + ' was added');
  });

  // On file deleted
  this.on('deleted', function(filepath) {
    console.log(filepath + ' was deleted');
  });

  // On changed/added/deleted
  this.on('all', function(event, filepath) {
    console.log(filepath + ' was ' + event);
  });

  // Get watched files with relative paths
  console.log(this.relative());
});

// Also accepts an array of patterns
gaze(['stylesheets/*.css', 'images/**/*.png'], function() {
  // Add more patterns later to be watched
  this.add(['js/*.js']);
});

var Gaze = require('gaze').Gaze;

var gaze = new Gaze('**/*');

// Files have all started watching
gaze.on('ready', function(watcher) { });

// A file has been added/changed/deleted has occurred
gaze.on('all', function(event, filepath) { });

gaze('**/*', function() {
  this.on('error', function(err) {
    // Handle error here
  });
});

See isaacs's minimatch for more information on glob patterns.

• patterns {String|Array} File patterns to be matched
• options {Object}
• callback {Function}
  • err {Error | null}
  • watcher {Object} Instance of the Gaze watcher

Create a Gaze object by instanting the gaze.Gaze class.

var Gaze = require('gaze').Gaze;
var gaze = new Gaze(pattern, options, callback);

• options The options object passed in.
  • interval {integer} Interval to pass to fs.watchFile
  • debounceDelay {integer} Delay for events called in succession for the same file/event

• ready(watcher) When files have been globbed and watching has begun.
• all(event, filepath) When an added, changed or deleted event occurs.
• added(filepath) When a file has been added to a watch directory.
• changed(filepath) When a file has been changed.
• deleted(filepath) When a file has been deleted.
• renamed(newPath, oldPath) When a file has been renamed.
• end() When the watcher is closed and watches have been removed.
• error(err) When an error occurs.
• nomatch When no files have been matched.

• emit(event, [...]) Wrapper for the EventEmitter.emit. added|changed|deleted events will also trigger the all event.
• close() Unwatch all files and reset the watch instance.
• add(patterns, callback) Adds file(s) patterns to be watched.
• remove(filepath) removes a file or directory from being watched. Does not recurse directories.
• watched() Returns the currently watched files.
• relative([dir, unixify]) Returns the currently watched files with relative paths.
  • dir {string} Only return relative files for this directory.
  • unixify {boolean} Return paths with / instead of \\ if on Windows.

I liked parts of other fs.watch wrappers but none had all the features I needed. This lib combines the features I needed from other fine watch libs: Speedy data behavior from paulmillr's chokidar, API interface from mikeal's watch and file globbing using isaacs's glob which is also used by cowboy's Grunt.

This is because of your system's max opened file limit. For OSX the default is very low (256). Increase your limit temporarily with ulimit -n 10480, the number being the new max limit.

In lieu of a formal styleguide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code using grunt.

• 0.5.2 - Fix for ENOENT error with non-existent symlinks.
• 0.5.1 - Use setImmediate (process.nextTick for node v0.8) to defer ready/nomatch events (@amasad).
• 0.5.0 - Process is now kept alive while watching files. Emits a nomatch event when no files are matching.
• 0.4.3 - Track file additions in newly created folders (@brett-shwom).
• 0.4.2 - Fix .remove() method to remove a single file in a directory (@kaelzhang). Fixing Cannot call method 'call' of undefined (@krasimir). Track new file additions within folders (@brett-shwom).
• 0.4.1 - Fix watchDir not respecting close in race condition (@chrisirhc).
• 0.4.0 - Drop support for node v0.6. Use globule for file matching. Avoid node v0.10 path.resolve/join errors. Register new files when added to non-existent folder. Multiple instances can now poll the same files (@jpommerening).
• 0.3.4 - Code clean up. Fix path must be strings errors (@groner). Fix incorrect added events (@groner).
• 0.3.3 - Fix for multiple patterns with negate.
• 0.3.2 - Emit end before removeAllListeners.
• 0.3.1 - Fix added events within subfolder patterns.
• 0.3.0 - Handle safewrite events, forceWatchMethod option removed, bug fixes and watch optimizations (@rgaskill).
• 0.2.2 - Fix issue where subsequent add calls dont get watched (@samcday). removeAllListeners on close.
• 0.2.1 - Fix issue with invalid added events in current working dir.
• 0.2.0 - Support and mark folders with path.sep. Add forceWatchMethod option. Support renamed events.
• 0.1.6 - Recognize the cwd option properly
• 0.1.5 - Catch too many open file errors
• 0.1.4 - Really fix the race condition with 2 watches
• 0.1.3 - Fix race condition with 2 watches
• 0.1.2 - Read triggering changed event fix
• 0.1.1 - Minor fixes
• 0.1.0 - Initial release

Copyright (c) 2013 Kyle Robinson Young
Licensed under the MIT license.