gulp-debounced-watch

File watcher that uses super-fast chokidar and emits vinyl objects and debounces the files individually.

Installation

Run npm install --save-dev gulp-debounced-watch.

Usage

var gulp = require('gulp'),
    watch = require('gulp-debounced-watch');
 
gulp.task('stream', function () {
    return gulp.src('css/**/*.css')
        .pipe(watch('css/**/*.css'))
        .pipe(gulp.dest('build'));
});
 
gulp.task('callback', function (cb) {
    watch('css/**/*.css', function () {
        gulp.src('css/**/*.css')
            .pipe(watch('css/**/*.css'))
            .on('end', cb);
    });
});
 
gulp.task('callback2', function (cb) {
    watch('css/**/*.css', function(vinyl) {
        gulp.src(vinyl.path)
            .pipe(gulp.dest('build'));
    });
});

Protip: until gulpjs 4.0 is released, you can use gulp-plumber to prevent stops on errors.

API

debouncedWatch(glob, [options, callback])

Creates a watcher that will spy on files that are matched by glob which can be a glob string or array of glob strings.

Returns a pass through stream that will emit vinyl files (with additional event property) that corresponds to event on file-system.

Callback `function(vinyl)`

This function is called when events happen on the file-system. All incoming files that are piped in are grouped and passed to the events stream as is.

vinyl — is vinyl object that corresponds to the file that caused the event. Additional event field is added to determine what caused changes.

Possible events:

add - file was added to watch or created
change - file was changed
unlink - file was deleted

Options

This object is passed to the chokidar options directly. Options for gulp.src are also available. If you do not want content from watch, then add read: false to the options object.

options.ignoreInitial

Type: Boolean
Default: true

Indicates whether chokidar should ignore the initial add events or not.

options.events

Type: Array
Default: ['add', 'change', 'unlink']

List of events, that should be watched by gulp-watch. Contains event names from chokidar.

options.base

Type: String
Default: undefined

Use explicit base path for files from glob. Read more about base and cwd in gulpjs docs.

options.name

Type: String
Default: undefined

Name of the watcher. If it is present in options, you will get more readable output.

options.verbose

Type: Boolean
Default: false

This option will enable verbose output.

options.readDelay

Type: Number
Default: 10

Wait for readDelay milliseconds before reading the file.

options.debounceImmediate

Type: Boolean Default: false

This option when set will issue a callback on the first event.

options.debounceTimeout

Type: Number Default: 1000

The number of milliseconds to debounce.

Methods

Returned Stream from constructor has some useful methods:

add(path / paths)
unwatch(path / paths)
close()

Events

All events from chokidar:

add, change, unlink, addDir, unlinkDir, error, ready, raw