In Gulp 4 should I now use .series() instead of .pipe()? - gulp

In gulp version 4 should I now use series() instead of pipe()? For example; my v3 task is below, should I change it to the last bit of code I've pasted? Is that the new gulp v4 way of doing things?
gulp.task('mytask', function() {
return gulp.src([
'scripts/a.js',
'scripts/b.js',
'scripts/c.js',
])
.pipe(concat('all.js'))
.pipe(gulp.dest('./scripts'))
.pipe(rename('all.min.js'))
.pipe(uglify())
.pipe(gulp.dest('./scripts'));
});
New v4 way???
gulp.task('mytask', function() {
return gulp.src([
'scripts/a.js',
'scripts/b.js',
'scripts/c.js',
])
.series(
concat('all.js'),
gulp.dest('./scripts'),
rename('all.min.js'),
uglify(),
gulp.dest('./scripts')
);
});

In Gulp 4, series is used to run multiple tasks one after another, whereas pipe is used to transform a stream within a single task.
So you would change your task code to look like the following. The updated code returns a stream made with src and piped through some transformations.
exports.mytask = function() {
return gulp.src([
'scripts/a.js',
'scripts/b.js',
'scripts/c.js',
])
.pipe(concat('all.js'))
.pipe(gulp.dest('./scripts'))
.pipe(rename('all.min.js'))
.pipe(uglify())
.pipe(gulp.dest('./scripts'));
});
There are various ways you can make functions that are tasks. See the docs here for more information.
Once you've got several tasks created you can compose them with series or parallel. See here for more information on composing multiple tasks together.
exports.mytask1 = ...
exports.mytask2 = ...
exports.alltasks = gulp.series(
mytask1,
mytask2
);

Related

gulpfile.js - version 3 to 4 migration

Years back I setup vs code to somewhat replicate the current methods I was using to design my sites (using standalone apps). I decided at the time I would just stick to what I was using. Since those apps are no longer maintained I am coming across compiling issues now - the time has come to make the jump.
I am having trouble with my gulpfile.js which is from back when I originally tried this all out. I saved it in case I needed to return to using vs code. Problem is apparently this format no longer works because gulp has updated. All of this is basically foreign to me right now and while I understand what things are doing I don't understand enough to modify this to the current method for gulp 4^.
Any chance someone can help me out with this one? I've looked at the guides about series and parallel and so on. I guess it's easier for me to understand by looking at a working example.
my old gulpfile.js
var gulp = require('gulp');
var sass = require('gulp-sass');
var cleanCSS = require('gulp-clean-css');
var uglify = require('gulp-uglify');
//processes the scss files in this folder
//minimizes them
gulp.task('sass', function () {
return gulp.src('_config/scss/**/*.scss')
.pipe(sass().on('error', sass.logError))
.pipe(cleanCSS())
.pipe(gulp.dest('assets/css'));
});
//minifies all js files in this folder
gulp.task('js', function () {
return gulp.src('_config/js/**/*.js')
.pipe(uglify())
.pipe(gulp.dest('assets/js'));
});
//minifies all js files in this folder
gulp.task('scripts', function () {
return gulp.src('_config/scripts/**/*.js')
.pipe(uglify())
.pipe(gulp.dest('assets/scripts'));
});
//creates 'watchers' that run tasks on specific activities
gulp.task('watch', function () {
gulp.watch('_config/scss/**/*.scss', ['sass']);
gulp.watch('_config/js/**/*.js', ['js']);
gulp.watch('_config/scripts/**/*.js', ['scripts']);
gulp.watch('_config/img/**/*', ['img']);
});
//this is the default task that runs everything
gulp.task('default', ['sass', 'js', 'scripts', 'watch']);
You are not that far from where you need to be. Change this code:
gulp.task('watch', function () {
gulp.watch('_config/scss/**/*.scss', ['sass']);
gulp.watch('_config/js/**/*.js', ['js']);
gulp.watch('_config/scripts/**/*.js', ['scripts']);
gulp.watch('_config/img/**/*', ['img']);
});
gulp.task('default', ['sass', 'js', 'scripts', 'watch']);
to
gulp.task('watch', function () {
gulp.watch('_config/scss/**/*.scss', gulp.series('sass'));
gulp.watch('_config/js/**/*.js', gulp.series('js'));
gulp.watch('_config/scripts/**/*.js', gulp.series('scripts'));
gulp.watch('_config/img/**/*', gulp.series('img'));
});
gulp.task('default', gulp.series('sass', 'js', 'scripts', 'watch'));
gulp.task now has this signature: gulp.task([taskName], taskFunction)
Before gulp v3 used an array of tasks as the second argument. gulp v4 uses a function, like gulp.series() or gulp.parallel(), as the second argument. And gulp.series() takes a list of tasks as its arguments. Since you used the gulp.task() method to create your tasks, the task names in series should appear as strings, like 'sass', 'js', etc.
Note: The preferred way to create tasks in v4 is as functions like:
function scripts() {
return gulp.src('_config/scripts/**/*.js')
.pipe(uglify())
.pipe(gulp.dest('assets/scripts'));
});
Then you would use those function names in series as gulp.series(scripts, js) - not as strings. You should look into using this form of tasks.
gulp.watch() signature: gulp.watch(globs, [options], [task])
The [task] can be a single task name, like your 'sass' or a composed task, which just means one generated using series or parallel.
In your case, you are running only one task in each watch statement, so
gulp.watch('_config/scss/**/*.scss', 'sass');
should suffice. I showed them as composed tasks like:
gulp.watch('_config/scss/**/*.scss', gulp.series('sass'));
in case in the future you want to run more than one task upon a file change. In which case you could use something like:
gulp.watch('_config/scss/**/*.scss', gulp.series('sass', 'serve'));
for example.
Finally switch out gulp-uglify for gulp-terser. gulp-terser will handle es6 syntax that gulp-uglify cannot. gulp-terser

gulp stops server on error even with jshint included in gulpfile.js

I don't know why the server still stops whenever there's an error in my js files even though I have jshint in my gulpfile. I installed jshint and included it in my project because it reports errors in js files, but it's still failing. How can I fix this?
gulp.task('scripts', () => {
return gulp.src('assets/js/src/*.js')
.pipe(jshint())
.pipe(jshint.reporter('jshint-stylish', {beep: true}))
.pipe(concat('main.js'))
.pipe(gulp.dest('assets/js/build/'))
.pipe(uglify())
.pipe(gulp.dest('assets/js/'))
.pipe(browserSync.stream({stream: true}));
});
gulp-jshint does what you says it does: it reports errors in JavaScript files. Nothing more, nothing less. It doesn't prevent defective JavaScript files from reaching later pipe stages like uglify() (which throws up and thus stops your server if there's any error in a JavaScript file).
If you want to prevent defective JavaScript files from wrecking your server, you need to put all the jshint stuff into it's own task and make sure that task fails when any JavaScript file has an error:
gulp.task('jshint', () => {
return gulp.src('assets/js/src/*.js')
.pipe(jshint())
.pipe(jshint.reporter('jshint-stylish', {beep: true}))
.pipe(jshint.reporter('fail'))
});
Then you need to make your scripts task depend on that jshint task:
gulp.task('scripts', ['jshint'], () => {
return gulp.src('assets/js/src/*.js')
.pipe(concat('main.js'))
.pipe(gulp.dest('assets/js/build/'))
.pipe(uglify())
.pipe(gulp.dest('assets/js/'))
.pipe(browserSync.stream({stream: true}));
});
Now your scripts task will only run when the jshint task was successful. If any JavaScript file was defective jshint will output the error to the console while your server continues to run using the last good version of your JavaScript.
The simplest fix would be to use gulp-plumber to handle the error a little more gracefully:
var plumber = require("gulp-plumber");
gulp.task('scripts', () => {
return gulp.src('assets/js/src/*.js')
.pipe(plumber())
.pipe(jshint())
.pipe(jshint.reporter('jshint-stylish', {beep: true}))
.pipe(concat('main.js'))
.pipe(gulp.dest('assets/js/build/'))
.pipe(uglify())
.pipe(gulp.dest('assets/js/'))
.pipe(browserSync.stream({stream: true}));
});
Personally, I don't like that solution because it will prevent your minified file from being updated. Here's what I would recommend:
var jshintSuccess = function (file) {
return file.jshint.success;
}
gulp.task('scripts', () => {
return gulp.src('assets/js/src/*.js')
.pipe(sourcemaps.init())
.pipe(jshint())
.pipe(jshint.reporter('jshint-stylish', {
beep: true
}))
.pipe(gulpif(jshintSuccess, uglify()))
.pipe(concat('main.js'))
.pipe(sourcemaps.write('maps'))
.pipe(gulp.dest('assets/js/'))
.pipe(browserSync.stream({
stream: true
}));
});
First, notice that I'm not writing to multiple destinations. Instead, I'm using sourcemaps so that you don't need unminified code. Second, I'm using gulp-if to conditionally pipe your code through uglify based on the results of jshint. Code with errors will bypass uglify so that it still makes it into to your destination file.
Now, you can inspect and debug it with the developer tools.
Note: I recommend this for local development only. I wouldn't connect this to a continuous integration pipeline because you'll only want good code to make it into production. Either set up a different task for that or add another gulp-if condition to prevent broken code from building based on environment variables.

Doing multiple things with a Gulp Task

I'm attempting to integrate Gulp into a project I'm working on. Everytime that I think I understand it, I run into a scenario where I'm total confused.
Basically, I'm trying to generate two files and copy another file. Currently, I have the following:
var input = {
file1: [
'src/library/**/*.js'
],
file2: [
'src/children/**/*.html'
]
file3: [
'src/index.html'
]
};
var output = {
dir: './dist',
file1 : 'app.js',
file2: 'app.html'
}
gulp.task('myTask', function() {
var stream1 = gulp.src(input.file1)
.pipe(concat(output.file1))
.pipe(gulp.dest('dist'))
;
var stream2 = gulp.src(input.file2)
.pipe(concat(output.file2))
.pipe(gulp.dest('dist'))
;
var stream3 = gulp.src(input.file3)
.pipe(gulp.dest('dist')
;
});
At this point, I understand that I basically have three streams. If I had a single stream, I would just do something like:
return gulp.src(input.file1)
...
.pipe(gulp.dest('dist'))
;
Clearly, that approach won't work. Yet, I cannot have my process move on until all three of my items happen. How do I resolve this in the gulp world?
It sounds like you have some clearly defined tasks:
Concatenate library JavaScript files.
Concatenate source files.
Copy index.html to the distribution directory.
Why not make each task it's own individual task?
For example:
gulp.task('concat:libs', function() {
return gulp.src(input.file1)
.pipe(concat(output.file1))
.pipe(gulp.dest('dist'));
});
gulp.task('concat:src', function(){
return gulp.src(input.file2)
.pipe(concat(output.file2))
.pipe(gulp.dest('dist'));
});
gulp.task('copy', function(){
return gulp.src(input.file3)
.pipe(gulp.dest('dist');
});
Then you can simply create a fourth task that depends on the other three:
gulp.task('myTask', ['concat:libs', 'concat:src', 'copy']);
The array in myTask's declaration indicate dependencies on the other three tasks, and gulp will execute those three tasks before executing myTask.
For more information see: https://github.com/gulpjs/gulp/blob/master/docs/API.md#gulptaskname-deps-fn

how do I run a gulp task from two or more other tasks and pass the pipe through

This must be obvious but I can't find it. I want to preprocess my stylus/coffee files with a watcher in the dev environment and in production with a build task (isn't that common to all of us?) and also run a few more minification and uglification steps in production but I want to share the pipe steps common to both dev and production for DRY
The problem is that when I run the task which watches the files, the task which preprocesses does that to all the files since it has its own gulp.src statement which includes all stylus files.
How do I avoid compiling all files on watching while still keeping the compile task separate. Thanks
paths = {
jade: ['www/**/*.jade']
};
gulp.task('jade', function() {
return gulp.src(paths.jade).pipe(jade({
pretty: true
})).pipe(gulp.dest('www/')).pipe(browserSync.stream());
});
gulp.task('serve', ['jade', 'coffee'], function() {
browserSync.init({
server: './www'
});
watch(paths.jade, function() {
return gulp.start(['jade']);
});
return gulp.watch('www/**/*.coffee', ['coffee']);
});
One important thing in Gulp is not to duplicate pipelines. If you want to process your stylus files, it has to be the one and only stylus pipe. If you want to execute different steps in your pipe however, you have multiple choices. One that I would suggest would be a noop() function in conjunction with a selection function:
var through = require('through2'); // Gulp's stream engine
/** creates an empty pipeline step **/
function noop() {
return through.obj();
}
/** the isProd variable denotes if we are in
production mode. If so, we execute the task.
If not, we pass it through an empty step
**/
function prod(task) {
if(isProd) {
return task;
} else {
return noop();
}
}
gulp.task('stylus', function() {
return gulp.src(path.styles)
.pipe(stylus())
.pipe(prod(minifyCss())) // We just minify in production mode
.pipe(gulp.dest(path.whatever))
})
As for the incremental builds (building just the changed files with every iteration), the best way would be to get on the gulp-cached plugin:
var cached = require('gulp-cached');
gulp.task('stylus', function() {
return gulp.src(path.styles)
.pipe(cached('styles')) // we just pass through the files that have changed
.pipe(stylus())
.pipe(prod(minifyCss()))
.pipe(gulp.dest(path.whatever))
})
This plugin will check if the contents have changed with each iteration you have done.
I spend a whole chapter on Gulp for different environments in my book, and I found those to be the most suitable ones. For more information on incremental builds, you can also check on my article on that (includes Gulp4): http://fettblog.eu/gulp-4-incremental-builds/

Creating a style guide / pattern library with gulp

I know there is already a tonne of automated tools to create a style guide / pattern library but in the interest of learning I'd like to see if I can roll my own.
Compiling the SASS is straight forward. Same with the js. I can also see how to wrap blocks of HTML from multiple files with a class and compiled into a single file. Ideal for displaying all the 'partials' together on one page.
gulp.task('inject:wrap', function(){
return gulp.src('./_patterns/*/*/*.html')
/// get the partial html filename here and insert below ###
.pipe(inject.wrap('<div id="###" class="pattern">', '</div>'))
.pipe(concat('patterns.html'))
.pipe(gulp.dest('build'));
});
gulp.task('process', ['inject:wrap']);
What I struggling with is how I can get the filename of the block - let's say _button.html - and pass this to the wrapper as the element id "###" above. Which I can then use to build the style guides navigation / anchor links.
Here's a sample code I've got, uses jade template language (which takes care of injections, partials, evaluation etc. by itself); There are two tasks, one generates static HTML pages, other pre-compiles templates to be used as runtime template functions wrapped in AMD
// preprocess & render jade static templates
gulp.task('views:preprocess', function () {
return gulp.src([ 'source/views/*.jade', '!source/views/layout.jade' ])
.pipe(plumber()) // plumber, because why not?
.pipe(data(function (file) {
// prepare data to be passed to the template
// here we can use the file name to map specific data to each file
return _.assign(settingsData, { timestamp: timestamp });
}))
// render template with data
.pipe(jade())
.pipe(gulp.dest('destination'));
});
// precompile jade runtime templates
gulp.task('views:precompile', function () {
// grab folder names
var folders = fs.readdirSync('source/templates').filter(function (file) {
return fs.statSync(path.join('source/templates', file)).isDirectory();
});
// create a separate task for each folder
var tasks = folders.map(function (folder) {
return gulp.src(path.join('source/templates', folder, '*.jade'))
.pipe(plumber())
// pre-compile the template as functions, for runtime
.pipe(jade({
client: true
}))
// wrap it in AMD, so we can use stuff like require.js to fetch them later
.pipe(wrap({
moduleRoot: 'source/templates',
modulePrefix: 'templates',
deps: [ 'jade' ],
params: [ 'jade' ]
}))
// concat all the templates in each folder to a single .js file
.pipe(concat(folder + '.js'))
.pipe(uglify())
.pipe(header(banner, { package: packageData }))
.pipe(gulp.dest('destination/scripts/templates'));
});
return merge(tasks);
});
Modules I've used are merge-stream, path, gulp, fs, gulp-data, gulp-jade, gulp-plumber etc.
Didn't quite understand what you're trying to achieve, but I hope this gives you some clues.