API.md

gulp API docs

gulp.src(globs[, options])

Takes a glob and represents a file structure. Can be piped to plugins.

gulp.src('./client/templates/*.jade')
    .pipe(jade())
    .pipe(minify())
    .pipe(gulp.dest('./build/minified_templates'));

globs

Type: String or Array

Glob or globs to read.

options

Type: Object

Options to pass to node-glob through glob-stream.

gulp adds two additional options in addition to the options supported by node-glob:

options.buffer

Type: Boolean Default: true

Setting this to false will return file.contents as a stream and not buffer files. This is useful when working with large files. Note: Plugins may not implement support for streams.

options.read

Type: Boolean Default: true

Setting this to false will return file.contents as null and not read the file at all.

gulp.dest(path)

Can be piped to and it will write files. Re-emits all data passed to it so you can pipe to multiple folders.

gulp.src('./client/templates/*.jade')
  .pipe(jade())
  .pipe(gulp.dest('./build/templates'))
  .pipe(minify())
  .pipe(gulp.dest('./build/minified_templates'));

path

Type: String

The path (folder) to write files to.

gulp.task(name[, deps], fn)

Define a task using Orchestrator.

gulp.task('somename', function() {
  // Do stuff
});

name

The name of the task. Tasks that you want to run from the command line should not have spaces in them.

deps

Type: Array

An array of tasks to be executed and completed before your task will run.

gulp.task('mytask', ['array', 'of', 'task', 'names'], function() {
  // Do stuff
});

Note: If the dependencies are asynchronous it is not guaranteed that they will finish before mytask is executed. To ensure they are completely finished, you need to make sure the dependency tasks have asynchronous support through one of the methods outlined below.

fn

The function that performs the task's operations. Generally this takes the form of gulp.src().pipe(someplugin()).

Async task support

Tasks can be made asynchronous if its fn does one of the following:

Accept a callback

gulp.task('somename', function(cb) {
  // Do stuff
  cb(err);
});

Return a stream

gulp.task('somename', function() {
  var stream = gulp.src('./client/**/*.js')
    .pipe(minify())
    .pipe(gulp.dest('/build');
  return stream;
});

Return a promise

var Q = require('q');

gulp.task('somename', function() {
  var deferred = Q.defer();

  // Do async stuff
  setTimeout(function() {
    deferred.resolve();
  }, 1);

  return deferred.promise;
});

gulp.run(tasks...[, cb])

tasks

Type: String

Tasks to be executed. You may pass any number of tasks as individual arguments. Note: Tasks are run concurrently and therefore do not run in order, see Orchestrator for more information.

gulp.run('scripts', 'copyfiles', 'builddocs');

gulp.run('scripts', 'copyfiles', 'builddocs', function(err) {
  // All done or aborted due to err
});

Use gulp.run to run tasks from other tasks. You will probably use this in your default task and to group small tasks into larger tasks.

gulp.watch(glob [, opts], cb)

glob

Type: String or Array

A single glob or array of globs that indicate which files to watch for changes.

opts

Type: Object

Options, that are passed to gaze.

cb(event)

Type: Function

Callback to be called on each change.

gulp.watch('js/**/*.js', function(event) {
  console.log('File '+event.path+' was '+event.type+', running tasks...');
  gulp.run('scripts', 'copyfiles');
});

The callback will be passed an object, event, that describes the change:

event.type

Type: String

The type of change that occurred, either added, changed or deleted.

event.path

Type: String

The path to the file that triggered the event.

gulp.env

gulp.env is a node-optimist arguments object. For instance, if you run:

gulp test dostuff --production

Which results in the following gulp.env:

{
  _: ['test', 'dostuff'],
  production: true
}

You can use this to conditionally enable certain plugins:

gulp.task('scripts', function() {
  var stream = gulp.src(['client/js/**/*.js', '!client/js/vendor/**']);

  // Only uglify in production
  if (gulp.env.production) {
    stream = stream.pipe(uglify());
  }

  stream.pipe(gulp.dest('build/js'));
});

There is also gulp-if to make this a lot prettier.