gulpfile.js

'use strict';
const gulp = require('gulp');
const events = require('events');
const eventEmitter = new events.EventEmitter();
const sass = require('gulp-sass');
const sourcemaps = require('gulp-sourcemaps');
const autoprefixer = require('gulp-autoprefixer');
const prompt = require('gulp-prompt');
const gutil = require('gulp-util');
const browserSync = require('browser-sync').create();
const fs = require('fs');
const gulpif = require('gulp-if');
const profilePath = './profile.json';
let useProfile = false;
let profile = {};
let profileDefaults = {
    serverUrl: 'http://example.net:10001/client/promo'
}

gulp.task('test', function(){ // delete me

});

gulp.task('load-profile', function() {
    fs.readFile(profilePath, 'utf8', function(err, data) {
        if (!err) {
            profile = JSON.parse(data);
            useProfile = true;
            eventEmitter.emit('profile-loaded');
        } else {
            if (err.code === 'ENOENT') {
                // profile file wasn't found, let's create one
                gulp.start('create-profile');
            } else {
                // something else went wrong. throw things
                throw err;
            }
        }
      
    });
});

gulp.task('create-profile', function(){
    gulp.src('./gulpfile.js')
        // ask question of the user for the profile file
        .pipe(prompt.prompt([{
            type: 'input',
            name: 'serverUrl',
            default: profileDefaults.serverUrl,
            message: 'What is the server URL?'
        }], function(res){
            // attach the answers to the profile object before writing the file
            profile.serverUrl = res.serverUrl;
            useProfile = true;
            eventEmitter.emit('profile-loaded');

            fs.writeFile(profilePath, JSON.stringify(profile), 'utf8');
        }));
});

gulp.task('reset-profile', function(){
    fs.access(profilePath, fs.F_OK, function(err) {
        if (!err) {
            fs.unlink(profilePath);
        } else {
            gutil.log(gutil.colors.red('No profile file found.'));
        }
    });
});

gulp.task('sass', function () {
    gulp.src('public/scss/**/*.scss')
        .pipe(sourcemaps.init())
        .pipe(sass().on('error', sass.logError))
        .pipe(autoprefixer({
            browsers: ['last 2 versions', 'ie 9'],
            cascade: false,
            remove: true
        }))
        .pipe(sourcemaps.write())
        .pipe(gulp.dest('public/css/'))
        .pipe(gulpif(useProfile, browserSync.stream()));
});

// Static Server + watching scss/html files
gulp.task('serve', function() {
    if (profile.serverUrl && profile.serverUrl.length) {
        gutil.log(gutil.colors.blue('Serving up:'), gutil.colors.bgBlue(profile.serverUrl));
        browserSync.init({
            proxy: profile.serverUrl
        });

        gulp.watch('public/scss/**/*.scss', ['sass']);
        gulp.watch([
            // Array of files to watch, changes reload the server
            'copydeck/**/*.yml', 
            'public/js/*.js', 
            'public/css/*.css',
            'public/css/**/*.css'
        ]).on('change', browserSync.reload);
    } else {
        gutil.log(gutil.colors.red('No server URL found.'));
    }
});

gulp.task('reset', ['reset-profile'], function(){});

gulp.task('default', ['load-profile', 'sass'], function() {
    eventEmitter.on('profile-loaded', function(){
        gulp.start('serve')
    });
    gulp.watch('public/scss/**/*.scss', ['sass']);
});