gulp.js

const gulp = require('gulp');
const sass = require('gulp-sass');
const cssnano = require('gulp-cssnano');
const rev = require('gulp-rev');

const uglify = require('gulp-uglify-es');
const imagemin = require('gulp-imagemin');
const del = require('del');

gulp.task('css', function(done){
    gulp.src('./assets/sass/**/*.scss')
    .pipe(sass())
    .pipe(cssnano())
    .pipe(gulp.dest('./assets.css'));

    return gulp.src('./assets/*/*.css')
    .pipe(rev())
    .pipe(gulp.dest('./public/assets'))
    .pipe(rev.manifest({
        cwd:'public',
        merge:true
    }))
    .pipe(gulp.dest('./pulic/assets'));
    done();
});

gulp.task('js',function(done){
    gulp.src('./assets/**/*.js')
    .pipe(uglify())
    .pipe(rev())
    .pipe(gulp.dest('./public/assets'))
    .pipe(rev.manifest({
        cwd:'public',
        merge:true
    }))
    .pipe(gulp.dest('./pulic/assets'));
    done();
});


gulp.task('images',function(done){
    gulp.src('./assets/**/*.+(png|jpg|gif|svg|jpeg)')
    .pipe(imagemin())
    .pipe(rev())
    .pipe(gulp.dest('./public/assets'))
    .pipe(rev.manifest({
        cwd:'public',
        merge:true
    }))
    .pipe(gulp.dest('./pulic/assets'));
    done();
});

gulp.task('clean:assets', function(done){
    del.deleteSync('./public/assets');
    done();
});

gulp.task('build', gulp.series('clean:assets', 'css', 'js', 'images'), function(done){
    done();
});