Develop Reference

Trouble with splitting gulpfile.js into multiple files in Gulp 4

I am a beginner to Javascript and Gulp. Am learning this based on a udemy course in which Gulp 3 is being used, and I've been looking at docs to convert the code to Gulp 4. It's been fun so far since I am learning more when I am doing the conversions myself, but am stuck on this one. Wonder if you guys can offer some advice.
Issue: When I split the gulpfile.js into separate files to organise my files better, it starts throwing errors. Code below.
styles.js
var gulp = require('gulp'),
postcss = require('gulp-postcss'),
autoprefixer = require('autoprefixer'),
cssvars = require('postcss-simple-vars'),
nested = require('postcss-nested'),
cssImport = require('postcss-import');
function styles(cb) {
return gulp.src('./app/assets/styles/styles.css')
.pipe(postcss([cssImport, cssvars, nested, autoprefixer]))
.pipe(gulp.dest('./app/temp/styles'));
cb();
}
exports.styles = styles;
watch.js
var gulp = require('gulp'),
browserSync = require('browser-sync').create();
function cssInject(cb) {
return gulp.src('./app/temp/styles/styles.css')
.pipe(browserSync.stream());
cb();
}
function browserSyncReload(cb) {
browserSync.reload();
cb();
}
function watch(cb) {
browserSync.init({
notify: false,
server: {
baseDir: "app"
}
});
watch('./app/index.html', browserSyncReload);
watch('./app/assets/styles/styles.css', gulp.series(cssInject, styles));
cb();
}
exports.browserSyncReload = browserSyncReload;
exports.watch = watch;
gulpfile.js
var stylesTasks = require('./gulp/tasks/styles.js'),
watchTasks = require('./gulp/tasks/watch.js');
exports.watch = watchTasks.watch;
exports.styles = stylesTasks.styles;
exports.browserSyncReload = watchTasks.browserSyncReload;
When I run "gulp watch", this is what I get.
error
$ gulp watch
[21:14:28] Using gulpfile ~/Projects/travel-site/gulpfile.js
[21:14:28] Starting 'watch'...
internal/async_hooks.js:195
function emitInitNative(asyncId, type, triggerAsyncId, resource) { ^
RangeError: Maximum call stack size exceeded
(Use `node --trace-uncaught ...` to show where the exception was thrown)
I found another post with almost identical code, but with a different error - which happened to be one of the errors i was getting earlier as well, and have followed the solution mentioned in that post - and that's when I get this error. Here's the link to the post.
Any help is much appreciated. Thanks for your time.

I have a full article that shows many how to regarding going from gulp3 to gulp4, I think you are going to find everything you need there
But basically, I think you need to take a look at these modules :
gulp-task-loader-recursive
gulp4-run-sequence
require-dir
Then, from a gulp.js perspective, you can end up with something like this :
// gulpfile.js
global.config = require('./gulp/config/config.json');
require('events').EventEmitter.prototype._maxListeners = 1000;
require('require-dir')('./gulp/tasks/styles');
require('require-dir')('./gulp/tasks/watch');
//... etc ...
So you would be able to then create your styles task and export it :
var gulp = require('gulp'),
postcss = require('gulp-postcss'),
autoprefixer = require('autoprefixer'),
cssvars = require('postcss-simple-vars'),
nested = require('postcss-nested'),
cssImport = require('postcss-import');
function styles(cb) {
return gulp.src('./app/assets/styles/styles.css')
.pipe(postcss([cssImport, cssvars, nested, autoprefixer]))
.pipe(gulp.dest('./app/temp/styles'));
cb();
}
const stylesTask = task('styles', styles);
exports.stylesTask = stylesTask;
You can then validate its recognized by gulp :
gulp --tasks
If you correctly see your styles tasks, you should now be able to run your task by running :
gulp styles
Repeat those steps for the watch task.

Answering my own question feels wierd, but I found the solution after playing with it for couple of days. See below.
I needed to import styles into watch.js, and not gulpfile.js. That was my first mistake. To do this, I added the below line to watch.js
var styles = require('./styles').styles;
Then my gulpfile.js only needed two lines
gulpfile.js
var watchTask = require('./gulp/tasks/watch').watch;
exports.default = watchTask;
I also removed the variable gulp, instead created variables for src and dest. So, the rest of the code looked like below.
styles.js
var {src, dest} = require('gulp'),
postcss = require('gulp-postcss'),
autoprefixer = require('autoprefixer'),
cssvars = require('postcss-simple-vars'),
nested = require('postcss-nested'),
cssImport = require('postcss-import');
const styles = function (cb) {
return src('./app/assets/styles/styles.css')
.pipe(postcss([cssImport, cssvars, nested, autoprefixer]))
.pipe(dest('./app/temp/styles'));
cb();
}
exports.styles = styles;
watch.js
var styles = require('./styles').styles;
var {src, series, watch} = require('gulp'),
browserSync = require('browser-sync').create();
const cssInject = function (cb) {
return src('./app/temp/styles/styles.css')
.pipe(browserSync.stream());
cb();
}
const reload = function (cb) {
browserSync.reload();
cb();
}
const watchTask = function (cb) {
browserSync.init({
notify: false,
server: {
baseDir: "app"
}
});
watch('./app/index.html', reload);
watch('./app/assets/styles/styles.css', series(cssInject, styles));
cb();
}
exports.watch = watchTask;
Hence resolved! hope this helps someone else.

Gulp task failing only with gulp.watch()

I have written a gulp task which finds .json files in a directory, assumes there is a corresponding .atlas file, and inlines them into my JS project inside one object:
gulp.task('spine', function() {
var fs = require('fs');
function parseAtlas(atlasPath) {
var atlas = fs.readFileSync(atlasPath, 'utf8').replace(/[ ]/g, '');
return JSON.stringify(atlas);
}
return gulp.src(config.src+'spineData/*.json')
.pipe(tap(function(file) {
var path = file.path.split('/');
var fullName = path.pop();
var name = fullName.split('.')[0];
path = path.join('/')+'/';
var atlas = parseAtlas(path+name+'.atlas');
var json = file.contents;
file.contents = Buffer.concat([
new Buffer("var app = (function(mod) { mod.pixi.spineData['"+name+"'] = {\n"),
new Buffer("atlas: "+atlas+",\n"),
new Buffer("json: "+json+"\n"),
new Buffer("}; return mod; })(app || {});")
]);
}))
.pipe(uglifyJS('data.min.js', {
outSourceMap: true,
basePath: config.dest,
sourceRoot: '/'
}))
.on('error', util.handleErrors)
.pipe(gulp.dest(config.dest));
});
The task works as expected except when using gulp.watch(). An external program changes file.json and the task fails with:
gulp-uglifyjs - UglifyJS threw an error
error: Unexpected token: punc (})
I am guessing it's something to do with gulp.watch() being called before the .json file is completely written by the external program. These are fairly big files - currently at around 6000 lines.
I've tried adding a delay (using gulp-wait) both before the tap pipe and the uglify pipe but still always fails with gulp.watch().

add livereload to broccoli

I'm trying to add livereload to broccoli
Unfortunately the live-reload plugin documentation is a bit short and I cannot get it to work. In the docs it is stated to do the following:
var injectLivereload = require('broccoli-inject-livereload');
var public = injectLivereload('public');
I figured that this should be placed inside the Brocfile.js (right?). But whatever I do nothing gets reloaded (I have to hit reload to refresh) I've also changed the 'public' part, which I think is representing a directory. Any help would be appreciated.

I'm using BrowserSync instead of "only" LiveReload. It also supports LiveReload (and LiveInject for CSS), but it has tons of other features as well (like ghosting).
Let's create a file called server.js and a folder called app next to it, where you put our index.html, .css and .js. This server.js contains:
var broccoli = require("broccoli");
var brocware = require("broccoli/lib/middleware");
var mergeTrees = require("broccoli-merge-trees");
var Watcher = require("broccoli-sane-watcher");
var browserSync = require("browser-sync");
var tree = mergeTrees(["app"]); // your public directory
var builder = new broccoli.Builder(tree);
var watcher = new Watcher(builder);
watcher.on("change", function(results) {
if (!results.filePath) return;
// Enable CSS live inject
if (results.filePath.indexOf("css") > -1) {
return browserSync.reload("*.css");
}
browserSync.reload();
});
browserSync({
server: {
baseDir: "./",
middleware: brocware(watcher)
}
});
Now fire the server (which will open the browser automatically):
node server.js
I know this isn't as straightforward as Gulp or Grunt at first sight, but it offers fine grained control over everything and it's really blazing fast, even if your app grows and grows.

Instead of Livereload I opted to use Browsersync via the Broccoli Browser Sync plugin
My final Brocfile.js was very similar to (pulled from plugins npm page):
var fastBrowserify = require('broccoli-fast-browserify');
var babelify = require('babelify');
var mergeTrees = require('broccoli-merge-trees');
var compileSass = require('broccoli-sass-source-maps');
var funnel = require('broccoli-funnel');
var BrowserSync = require('broccoli-browser-sync');
var optionalTransforms = [
'regenerator'
// 'minification.deadCodeElimination',
// 'minification.inlineExpressions'
];
var babelOptions = {stage: 0, optional: optionalTransforms, compact: true};
// var browserifyOpts = {deps: true, entries: files, noParse: noParse, ignoreMissing: true};
var transformedBabelify = fastBrowserify('app', {
browserify: {
extensions: [".js"]
},
bundles: {
'js/app.js': {
entryPoints: ['app.js'],
transform: {
tr: babelify,
options: {
stage: 0
}
}
}
}
});
var appCss = compileSass(['piggy/frontend/app'], 'main.scss', 'css/app.css');
var staticFiles = funnel('frontend', {
srcDir: 'static'
});
var browserSync = new BrowserSync([staticFiles, transformedBabelify, appCss]);
module.exports = mergeTrees([staticFiles, transformedBabelify, appCss, browserSync]);
With this solution I was able to continue using broccoli to serve my assets via broccoli serve and all my assets would be rebuilt then reloaded in the browser including my css.

Chain Gulp glob to browserify transform

I have a project with a few relatively disjoint pages, each including their own entry point script. These scripts require a number of others using commonjs syntax, and need to be transformed by 6to5 and bundled by browserify.
I would like to set up a gulp task that captures all the files matching a pattern and passes them on to the bundler, but I'm not sure how to pass files from gulp.src to browserify(filename).
My gulpfile looks like:
var gulp = require("gulp");
var browserify = require("browserify");
var to5browserify = require("6to5-browserify");
var source = require("vinyl-source-stream");
var BUNDLES = [
"build.js",
"export.js",
"main.js"
];
gulp.task("bundle", function () {
/* Old version, using glob:
return gulp.src("src/** /*.js")
.pipe(sixto5())
.pipe(gulp.dest("dist"));
*/
// New version, using array:
return BUNDLES.map(function (bundle) {
return browserify("./src/" + bundle, {debug: true})
.transform(to5browserify)
.bundle()
.pipe(source(bundle))
.pipe(gulp.dest("./dist"));
});
});
gulp.task("scripts", ["bundle"]);
gulp.task("html", function () {
return gulp.src("src/**/*.html")
.pipe(gulp.dest("dist"));
});
gulp.task("styles", function () {
return gulp.src("src/**/*.css")
.pipe(gulp.dest("dist"));
});
gulp.task("default", ["scripts", "html", "styles"]);
This seems to work, but isn't maintainable: I'll be adding more scripts relatively soon, and don't want to add them to the array every time.
I've tried using gulp.src(glob).pipe within the browserify call and piping after calling (shown here), and gulp.src(glob).map (method doesn't exist).
How can you chain gulp.src with a name-based transformer like browserify?

Use through2 to make a one-off custom plugin stream that does all of the dirty work.
Unfortanately vinyl-transform and vinyl-source-stream and the solutions that go along with those have flaws so we have to go for something custom.
var gulp = require('gulp');
var through = require('through2');
var browserify = require('browserify');
gulp.task('bundle', function() {
var browserified = function() {
return through.obj(function(chunk, enc, callback) {
if(chunk.isBuffer()) {
var b = browserify(chunk.path);
// Any custom browserify stuff should go here
//.transform(to5browserify);
chunk.contents = b.bundle();
this.push(chunk);
}
callback();
});
};
return gulp.src(['./src/**/*.js'])
.pipe(browserified())
.pipe(gulp.dest('dest'));
});

You can specify globs in your BUNDLES array as well as exclude any files:
var BUNDLES = [
"app/**/*.js",
"export.js",
"app/modules/**/*.js",
"!app/modules/excluded/*.js"
];

Iterating over directories with Gulp?

I'm new to gulp, but I'm wondering if its possible to iterate through directories in a gulp task.
Here's what I mean, I know a lot of the tutorials / demos show processing a bunch of JavaScript files using something like "**/*.js" and then they compile it into a single JavaScript file. But I want to iterate over a set of directories, and compile each directory into it's own JS file.
For instance, I have a file structure like:
/js/feature1/something.js
/js/feature1/else.js
/js/feature1/foo/bar.js
/js/feature1/foo/bar2.js
/js/feature2/another-thing.js
/js/feature2/yet-again.js
...And I want two files: /js/feature1/feature1.min.js and /js/feature2/feature2.min.js where the first contains the first 4 files and the second contains the last 2 files.
Is this possible, or am I going to have to manually add those directories to a manifest? It would be really nice to pragmatically iterate over all the directories within /js/.
Thanks for any help you can give me.
-Nate
Edit: It should be noted that I don't only have 2 directories, but I have many (maybe 10-20) so I don't really want to write a task for each directory. I want to handle each directory the same way: get all of the JS inside of it (and any sub-directories) and compile it down to a feature-based minified JS file.

There's an official recipe for this: Generating a file per folder
var fs = require('fs');
var path = require('path');
var merge = require('merge-stream');
var gulp = require('gulp');
var concat = require('gulp-concat');
var rename = require('gulp-rename');
var uglify = require('gulp-uglify');
var scriptsPath = 'src/scripts';
function getFolders(dir) {
return fs.readdirSync(dir)
.filter(function(file) {
return fs.statSync(path.join(dir, file)).isDirectory();
});
}
gulp.task('scripts', function() {
var folders = getFolders(scriptsPath);
var tasks = folders.map(function(folder) {
return gulp.src(path.join(scriptsPath, folder, '/**/*.js'))
// concat into foldername.js
.pipe(concat(folder + '.js'))
// write to output
.pipe(gulp.dest(scriptsPath))
// minify
.pipe(uglify())
// rename to folder.min.js
.pipe(rename(folder + '.min.js'))
// write to output again
.pipe(gulp.dest(scriptsPath));
});
// process all remaining files in scriptsPath root into main.js and main.min.js files
var root = gulp.src(path.join(scriptsPath, '/*.js'))
.pipe(concat('main.js'))
.pipe(gulp.dest(scriptsPath))
.pipe(uglify())
.pipe(rename('main.min.js'))
.pipe(gulp.dest(scriptsPath));
return merge(tasks, root);
});

You could use glob to get a list of directories and iterate over them, using gulp.src to create a separate pipeline for each feature. You can then return a promise which is resolved when all of your streams have ended.
var fs = require('fs');
var Q = require('q');
var gulp = require('gulp');
var glob = require('glob');
gulp.task('minify-features', function() {
var promises = [];
glob.sync('/js/features/*').forEach(function(filePath) {
if (fs.statSync(filePath).isDirectory()) {
var defer = Q.defer();
var pipeline = gulp.src(filePath + '/**/*.js')
.pipe(uglify())
.pipe(concat(path.basename(filePath) + '.min.js'))
.pipe(gulp.dest(filePath));
pipeline.on('end', function() {
defer.resolve();
});
promises.push(defer.promise);
}
});
return Q.all(promises);
});

I am trying myself to get how streams work in node.
I made a simple example for you, on how to make a stream to filter folders and start a new given stream for them.
'use strict';
var gulp = require('gulp'),
es = require('event-stream'),
log = require('consologger');
// make a simple 'stream' that prints the path of whatever file it gets into
var printFileNames = function(){
return es.map(function(data, cb){
log.data(data.path);
cb(null, data);
});
};
// make a stream that identifies if the given 'file' is a directory, and if so
// it pipelines it with the stream given
var forEachFolder = function(stream){
return es.map(function(data, cb){
if(data.isDirectory()){
var pathToPass = data.path+'/*.*'; // change it to *.js if you want only js files for example
log.info('Piping files found in '+pathToPass);
if(stream !== undefined){
gulp.src([pathToPass])
.pipe(stream());
}
}
cb(null, data);
});
};
// let's make a dummy task to test our streams
gulp.task('dummy', function(){
// load some folder with some subfolders inside
gulp.src('js/*')
.pipe(forEachFolder(printFileNames));
// we should see all the file paths printed in the terminal
});
So in your case, you can make a stream with whatever you want to make with the files in a folder ( like minify them and concatenate them ) and then pass an instance of this stream to the forEachFolder stream I made. Like I do with the printFileNames custom stream.
Give it a try and let me know if it works for you.

First, install gulp-concat & gulp-uglify.
$ npm install gulp-concat
$ npm install gulp-uglify
Next, do something like:
//task for building feature1
gulp.task('minify-feature1', function() {
return gulp.src('/js/feature1/*')
.pipe(uglify()) //minify feature1 stuff
.pipe(concat('feature1.min.js')) //concat into single file
.pipe(gulp.dest('/js/feature1')); //output to dir
});
//task for building feature2
gulp.task('minify-feature2', function() { //do the same for feature2
return gulp.src('/js/feature2/*')
.pipe(uglify())
.pipe(concat('feature2.min.js'))
.pipe(gulp.dest('/js/feature2'));
});
//generic task for minifying features
gulp.task('minify-features', ['minify-feature1', 'minify-feature2']);
Now, all you have to do to minify everything from the CLI is:
$ gulp minify-features

I had trouble with the gulp recipe, perhaps because I'm using gulp 4 and/or because I did not want to merge all my folders' output anyway.
I adapted the recipe to generate (but not run) an anonymous function per folder and return the array of functions to enable them to be processed by gulp.parallel - in a way where the number of functions I would generate would be variable. The keys to this approach are:
Each generated function needs to be a function or composition (not a stream). In my case, each generated function was a series composition because I do lots of things when building each module folder.
The array of functions needs to passed into my build task using javascript apply() since every member of the array needs to be turned into an argument to gulp.parallel in my case.
Excerpts from my function that generates the array of functions:
function getModuleFunctions() {
//Get list of folders as per recipe above - in my case an array named modules
//For each module return a function or composition (gulp.series in this case).
return modules.map(function (m) {
var moduleDest = env.folder + 'modules/' + m;
return gulp.series(
//Illustrative functions... all must return a stream or call callback but you can have as many functions or compositions (gulp.series or gulp.parallel) as desired
function () {
return gulp.src('modules/' + m + '/img/*', { buffer: false })
.pipe(gulp.dest(moduleDest + '/img'));
},
function (done) {
console.log('In my function');
done();
}
);
});
}
//Illustrative build task, running two named tasks then processing all modules generated above in parallel as dynamic arguments to gulp.parallel, the gulp 4 way
gulp.task('build', gulp.series('clean', 'test', gulp.parallel.apply(gulp.parallel, getModuleFunctions())));
`