gulpfile.js

var gulp = require('gulp');
var $ = require('gulp-load-plugins')({ rename: { 'gulp-rev-delete-original': 'revdel', 'gulp-if': 'if' } });

gulp.task('copy', function () {
    return gulp.src(['sources/assets/{images,fonts,webfonts}/**/*', 'sources/app.yaml', 'sources/CNAME', 'sources/assets/files/*'], { base: 'sources' }).pipe(gulp.dest('docs'));
});

gulp.task('clean', function () {
    return gulp.src('docs/', { read: false }).pipe($.clean());
});

gulp.task('minify-js', function () {
    return gulp.src('sources/**/*.js').pipe($.uglify()).pipe(gulp.dest('docs/'));
});

gulp.task('minify-css', function () {
    return gulp
        .src('sources/**/*.css')
        .pipe($.cssnano({ safe: true }))
        .pipe(gulp.dest('docs/'));
});

gulp.task('minify-html', function () {
    return gulp
        .src('sources/**/*.html')
        .pipe($.htmlmin({ collapseWhitespace: true }))
        .pipe(gulp.dest('docs/'));
});

gulp.task('useref', function () {
    return gulp
        .src('frontend/index.html')
        .pipe($.useref())
        .pipe($.if('*.html', $.inlineSource()))
        .pipe($.if('*.html', $.htmlmin({ collapseWhitespace: true })))
        .pipe($.if('*.js', $.uglify()))
        .pipe($.if('*.css', $.cssnano({ safe: true })))
        .pipe(gulp.dest('docs'));
});

gulp.task('imagemin', function () {
    return gulp
        .src('frontend/assets/images/*')
        .pipe(
            $.imagemin({
                progressive: true,
                svgoPlugins: [{ removeViewBox: false }, { cleanupIDs: false }],
            }),
        )
        .pipe(gulp.dest('docs/assets/images'));
});

gulp.task('rev', function () {
    return gulp.src(['docs/**/*.{css,js,jpeg,png}']).pipe($.rev()).pipe($.revdel()).pipe(gulp.dest('docs/')).pipe($.rev.manifest()).pipe(gulp.dest('docs/'));
});

gulp.task('revreplace', ['rev'], function () {
    return gulp
        .src(['docs/index.html', 'docs/works-2.html', 'docs/app.yaml', 'docs/**/*.css'])
        .pipe(
            $.revReplace({
                manifest: gulp.src('docs/rev-manifest.json'),
                replaceInExtensions: ['.html', '.yaml', '.js', '.css', '.png'],
            }),
        )
        .pipe(gulp.dest('docs/'));
});

gulp.task('build', $.sequence(['clean', 'copy', 'minify-js', 'minify-css', 'minify-html', 'imagemin'], 'useref', 'revreplace'));
gulp.task('default', $.sequence('build'));