gulp-filter

Filter files in a vinyl stream

Enables you to work on a subset of the original files by filtering them using glob patterns. When you're done and want all the original files back, you just use the restore stream.

Install

$ npm install --save-dev gulp-filter

Usage

Filter only

You may want to just filter the stream content:

const gulp = require('gulp');
const uglify = require('gulp-uglify');
const filter = require('gulp-filter');

exports.default = () => {
	// Create filter instance inside task function
	const f = filter(['**', '!*src/vendor']);

	return gulp.src('src/**/*.js')
		// Filter a subset of the files
		.pipe(f)
		// Run them through a plugin
		.pipe(uglify())
		.pipe(gulp.dest('dist'));
};

Restoring filtered files

const gulp = require('gulp');
const uglify = require('gulp-uglify');
const filter = require('gulp-filter');

exports.default = () => {
	// Create filter instance inside task function
	const f = filter(['**', '!*src/vendor'], {restore: true});

	return gulp.src('src/**/*.js')
		// Filter a subset of the files
		.pipe(f)
		// Run them through a plugin
		.pipe(uglify())
		// Bring back the previously filtered out files (optional)
		.pipe(f.restore)
		.pipe(gulp.dest('dist'));
};

Multiple filters

By combining and restoring different filters you can process different sets of files with a single pipeline.

const gulp = require('gulp');
const less = require('gulp-less');
const concat = require('gulp-concat');
const filter = require('gulp-filter');

exports.default = () => {
	const jsFilter = filter('**/*.js', {restore: true});
	const lessFilter = filter('**/*.less', {restore: true});

	return gulp.src('assets/**')
		.pipe(jsFilter)
		.pipe(concat('bundle.js'))
		.pipe(jsFilter.restore)
		.pipe(lessFilter)
		.pipe(less())
		.pipe(lessFilter.restore)
		.pipe(gulp.dest('out/'));
};

Restore as a file source

You can restore filtered files in a different place and use it as a standalone source of files (ReadableStream). Setting the passthrough option to false allows you to do so.

const gulp = require('gulp');
const uglify = require('gulp-uglify');
const filter = require('gulp-filter');

exports.default = () => {
	const f = filter(['**', '!*src/vendor'], {restore: true, passthrough: false});

	const stream = gulp.src('src/**/*.js')
		// Filter a subset of the files
		.pipe(f)
		// Run them through a plugin
		.pipe(uglify())
		.pipe(gulp.dest('dist'));

	// Use filtered files as a gulp file source
	f.restore.pipe(gulp.dest('vendor-dist'));

	return stream;
};

API

filter(pattern, options?)

Returns a transform stream with a .restore property.

pattern

Type: string | string[] | Function

Accepts a string/array with globbing patterns which are run through multimatch.

If you supply a function, you'll get a vinyl file object as the first argument and you're expected to return a boolean of whether to include the file:

filter(file => /unicorns/.test(file.path));

options

Type: object

Accepts minimatch options.

Note: Set dot: true if you need to match files prefixed with a dot, for example, .gitignore.

restore

Type: boolean
Default: false

Restore filtered files.

passthrough

Type: boolean
Default: true

When set to true, filtered files are restored with a stream.PassThrough, otherwise, when set to false, filtered files are restored as a stram.Readable.

When the stream is a stream.Readable, it ends by itself, but when it's stream.PassThrough, you are responsible of ending the stream.