Gulp.js run tasks in specific order blocking

Question

Using gulp.js I have three tasks (uglify, buildHTML, rmRevManifest) I'd like to run as part of a parent build task. The code I have works, excepts it runs the tasks in parallel (i.e. order is not preserved). How can I have the tasks block and not run the next until the previous finishes?

I.E. right now the execution order comes back as:

[11:50:17] gulp-notify: [Gulp notification] Deleted 'rev-manifest.json'.
[11:50:17] gulp-notify: [Gulp notification] Created 'build/index.html'.
[11:50:17] gulp-notify: [Gulp notification] Uglified JavaScript.

The order matters, and uglify should run first, then buildHTML, and finally rmRevManifest.

gulp.task('build', ['uglify', 'buildHTML', 'rmRevManifest'], function(cb) {
});

gulp.task('uglify', function(cb) {
    gulp.src('client/js/source/**/*.js')
        .pipe(concat('app'))
        .pipe(ngmin())
        .pipe(uglify())
        .pipe(rev())
        .pipe(rename({
            extname: ".min.js"
        }))
        .pipe(gulp.dest('client/js'))
        .pipe(rev.manifest())
        .pipe(gulp.dest('client/js'))
        .pipe(notify('Uglified JavaScript.'));
});

gulp.task('buildHTML', function(cb) {
    gulp.src('client/views/index.html')
        .pipe(replace(/app\-[a-fA-F0-9]\.min\.js/, 'app-.min.js'))
        .pipe(gulp.dest('client/build'))
        .pipe(notify('Created \'build/index.html\'.'));
});

gulp.task('rmRevManifest', function(cb) {
    gulp.src('client/js/rev-manifest.json', { read: false })
        .pipe(rimraf())
        .pipe(notify('Deleted \'rev-manifest.json\'.'));
});

Answer 1

An example of setting up dependencies in Gulp 3.0. In this example 3 tasks depend on the 'clean' task which should be executed first:

// Include Gulp
var gulp = require('gulp');
var task = {};

// Clean up
gulp.task('clean', function () { .. });

// HTML pages
gulp.task('pages', task.pages = function () { ... });
gulp.task('pages:clean', ['clean'], task.pages);

// CSS style sheets
gulp.task('styles', task.styles = function () { ... });
gulp.task('styles:clean', ['clean'], task.styles);

// JavaScript files
gulp.task('scripts', task.scripts = function () { ... });
gulp.task('scripts:clean', ['clean'], task.scripts);

// Bundling and optimization
gulp.task('build', ['pages:clean', 'styles:clean', 'scripts:clean']);

With run-sequence it would be equal to:

// Include Gulp & utilities
var gulp = require('gulp');
var runSequence = require('run-sequence');

// Clean up
gulp.task('clean', function () { .. });

// HTML pages
gulp.task('pages', function () { ... });

// CSS style sheets
gulp.task('styles', function () { ... });

// JavaScript files
gulp.task('scripts', function () { ... });

// Bundling and optimization
gulp.task('build', ['clean'], function (cb) {
    runSequence(['pages', 'styles', 'scripts'], cb);
});

P.S.: In the upcoming Gulp 4.0 the dependency system will be much better.

Answer 2

The real answer: you need to set up dependencies which require the other tasks to run first.

The easy answer: there's an npm module to do exactly what you need called run sequence.