I'm writing an app that uses many JS files. Underscore, Backbone, jQuery, jQuery plugins for sliders, several files for models, routers, collections and views.
In my dev machine, I load every file separately, but in production I use only one JS file (minified, gziped, less http req, etc.).
In my build process, each file in minified with UglifyJS and then concat into prod.js. Is this the correct way to build that file? Or should I concat each file into prod.js and then minify with UglifyJS?
Thanks a lot!
I tested the output of each method using Gulp.
Test Setup
I used 9 JavaScript files totaling 19.15 kB when concatenated (not minified). Each file starts with a 'use strict'; statement.
Results:
Concatenate => Uglify: 7.993 kB
Uglify => Concatenate: 8.093 kB
Difference: 0.1 kB
Notes:
Concatenate => Uglify strips 8 of the 9 'use strict'; statements
Uglify => Concatenate preserves all 'use strict'; statements
A single 'use strict'; statement is 13 bytes. 8 × 13 bytes = 104 bytes, which accounts for the 0.1 kB difference.
Final Thoughts:
Use whichever order you prefer.
The difference between these two processes is negligible. Concatenate => Uglify could (theoretically) produce (barely noticeably) smaller files if both of the following are true:
Several of the individual files start with a 'use strict'; statement
There are many individual files
Here's the gulpfile.js I used:
var gulp = require('gulp'),
concat = require('gulp-concat'),
uglify = require('gulp-uglify');
var files = [
'!app/scripts/**/*Spec.js', // Exclude test files
'app/scripts/**/*.js'
];
// Register tasks
gulp.task('concat-min', function() {
return gulp.src(files)
.pipe(concat('script.min.js'))
.pipe(uglify())
.pipe(gulp.dest('dist'));
});
gulp.task('min-concat', function() {
return gulp.src(files)
.pipe(uglify())
.pipe(concat('script.min.js'))
.pipe(gulp.dest('dist'));
});
I'd be surprised if either way round made a significant difference to the overhead of a user's request.
I'd also suggest that concatenating all these frameworks into one file may actually increase the overhead for each user.
Why?
When using a popular/common framework such as jQuery etc. it makes sense to host it on a CDN, such as Google to benefit from caching the file - if a user's visited a website that also made use of jQuery they won't need to download it at all! Not to mention decreased geographic latency.
So, by creating your own unique file you're making it much more likely that the user will have to download the entire thing.
I would alway put them all into one then minify.
One thing i have started doing is to run it though http://www.javascriptobfuscator.com/ first i know it sounds count-intuitive but one of the things it does is store all string in an array ok an ugly array but stops string repetition then when you go to Your minified, i use Google Closure compiler it will then tidy the strings up and you often end up with a better minified file
I strongly recommend you use requirejs, using that lib you can make packages or one minimized and unified file. Please read the optimization tool.
However, as Widor told you, It's not a good idea join ALL the files into one. Many of those libs performs better using the google api (CDN) if you always will use your app online
It won't make much difference, since the toplevel statements (and variables &c.) aren't touched.
However, when using the --lift-vars option, it could change. It depends heavily on your code.
Order would not matter much assuming you have less globals floating around. There would be very minimal file size difference. My personal preference is to Concatenate and then Uglify which allows you to generate better and accurate sourcemaps rather than other way round. (This is because sourcemaps change with each transformation). I am wondering what is the purpose of uglifying smaller files and then concatenating. Basically, it is up to you and choice is yours. Concatenating and Uglifying seems more satisfactory and less error prone
Related
My Angular 1 code works fine in development. But when I compress my Angular project to dist with Grunt, my directives run before my services and app.run(), which results in breaking the page.
I traced the issue to uglify which changes the code execution order. I don't know how to prevent my uglify from changing the execution order.
Below solution worked for me. May be this will help you too. I refered it from here.
Three solutions:
Make the grunt task do not include unwanted files, and include those files already minified in your app.
If problem still occurs after first solution, your angular modules are not "uglify friendly". There's a special way to declare your dependencies so that minifying goes smooth, as described on this page ("a note on minification" paragraph) for example. Please note that instead of doing this declaration "by hand", you can use the "ng-min" task that automatize the process and keep your code clean.
Well, in my case I still had issue, so I ended turning off the "mangle" option in uglify (that very option that make long strings into smaller to compress response size). You can turn off the option like this :
uglify: {
options: {
mangle: false
},
}
I want to minimize the number of HTTP requests from the client to load scripts in the browser. This is going to be a pretty general question but I still hope I can get some answers because module management in javascript has been a pain so far.
Current situation
Right now, in development, each module is requested individually from the main html template, like this:
<script src="/libraries/jquery.js"></script>
<script src="/controllers/controllername.js"></script>
...
The server runs on Node.js and sends the scripts as they are requested.
Obviously this is the least optimal way of doing so, since all the models, collections, etc. are also separated into their own files which translates into numerous different requests.
As far as research goes
The libraries I have come across (RequireJS using AMD and CommonJS) can request modules from within the main .js file sent to the client, but require a lot of additional work to make each module compliant with each library:
;(function(factory){
if (typeof define === 'function' && define.amd) define([], factory);
else factory();
}(function(){
// Module code
exports = moduleName;
}));
My goal
I'd like to create a single file on the server that 'concatenates' all the modules together. If I can do so without having to add more code to the already existing modules that would be perfect. Then I can simply serve that single file to the client when it is requested.
Is this possible?
Additionally, if I do manage to build a single file, should I include the open source libraries in it (jQuery, Angular.js, etc.) or request them from an external cdn on the client side?
What you are asking to do, from what I can tell, is concat your js files into one file and then in your main.html you would have this
<script src="/pathLocation/allMyJSFiles.js"></script>
If my assumption is correct, then the answer would be to use one of the two following items
GULP link or GRUNT link
I use GULP.
You can either use gulp on a case by case basis, which means calling gulp from the command line to execute gulp code, or use a watch to do it automatically on save.
Besides getting gulp to work and including the gulp files you need to do what you need, I will only provide a little of what I use to get your answer.
In my gulp file I would have something like this
var gulp = require('gulp');
var concat = require('gulp-concat');
...maybe more.
Then I have the file paths I need to be reduced into one file.
var onlyProductionJS = [
'public/application.js',
'public/directives/**/*.js',
'public/controllers/**/*.js',
'public/factories/**/*.js',
'public/filters/**/*.js',
'public/services/**/*.js',
'public/routes.js'
];
and I use this info in a gulp task like the one below
gulp.task('makeOneFileToRuleThemAll', function(){
return gulp.src(onlyProductionJS)
.pipe(concat('weHaveTheRing.js'))
.pipe(gulp.dest('public/'));
});
I then run the task in my command line by calling
gulp makeOneFileToRuleThemAll
This call runs the associated gulp task which uses 'gulp-concat' to get all the files together into one new file called 'weHaveTheRing.js' and creates that file in the destination 'public/'
Then just include that new file into your main.html
<script src="/pathLocation/weHaveTheRing.js"></script>
As for including all your files into one file, including your vendor files, just make sure that your vendor code runs first. It's probably best to keep those separate unless you have a sure fire way of getting your vendor code to load first without any issues.
UPDATE
Here is my gulp watch task.
gulp.task('startTheWatchingEye', function () {
gulp.watch(productionScripts, ['makeOneFileToRuleThemAll']);
});
Then I start up my server like this (yours may differ)
npm start
// in a different terminal window I then type
gulp startTheWatchfuleye
NOTE: you can use ANY movie or show reference you wish! :)
Now just code it up, every time you make a change in the specified files GULP will run your task(s).
If you want to say run Karma for your test runner...
add the following to your gulp file
var karma = require('karma').server;
gulp.task('karma', function(done){
karma.start({
configFile: __dirname + '/karma.conf.js'
}, done);
});
Then add this task karma to your watch I stated above like this...
gulp.task('startTheWatchingEye', function(){
gulp.watch(productionScripts, ['makeOneFileToRuleThemAll', 'karma']);
});
ALSO
Your specific settings may require a few more gulp modules. Usually, you install Gulp globally, as well as each module. Then use them in your various projects. Just make sure that your project's package.json has the gulp modules you need in dev or whatever.
There are different articles on whether to use Gulp or Grunt. Gulp was made after Grunt with a few additions that Grunt was lacking. I don't know if Grunt lacks them anymore. I like Gulp a lot though and find it very useful with a lot of documentation.
Good luck!
I'd like to create a single file on the server that 'concatenates' all the modules together. If I can do so without having to add more code to the already existing modules that would be perfect.
Sure you can. You can use Grunt or Gulp to do that, more specifically grunt-contrib-concat or gulp-concat
Here's an example of a Gruntfile.js configuration to concat every file under a js directory:
grunt.initConfig({
concat: {
dist: {
files: {
'dist/built.js': ['js/**/**.js'],
},
},
},
});
Also, you can minify everything after concatenating, using grunt-contrib-minify.
Both libraries support source maps so, in the case a bug gets to production, you can easily debug.
You can also minify your HTML files using grunt-contrib-htmlmin.
There's also an extremely useful library called grunt-usemin. Usemin let's you use HTML comments to "control" which files get minified (so you don't have to manually add them).
The drawback is that you have to explicitely include them in your HTML via script tags, so no async loading via javascript (with RequireJS for instance).
Additionally, if I do manage to build a single file, should I include the open source libraries in it (jQuery, Angular.js, etc.) or request them from an external cdn on the client side?
That's debatable. Both have pros and cons. Concatenating vendors assures that, if for some reason, the CDN isn't available, your page works as intended. However the file served is bigger so you consume more bandwidth.
In my personal experience, I tend to include vendor libraries that are absolutely essential for the page to run such as AngularJS for instance.
If I understand you correctly, you could use a task runner such as Grunt to concatenate the files for you.
Have a look at the Grunt Concat plugin.
Example configuration from the docs:
// Project configuration.
grunt.initConfig({
concat: {
dist: {
src: ['src/intro.js', 'src/project.js', 'src/outro.js'],
dest: 'dist/built.js',
}
}
});
Otherwise, as you have stated, a 'module loader' system such as Require JS or Browserify may be the way to go.
Has any one had any success with this?
I think it's more or less an unsolved problem:
https://github.com/jashkenas/coffee-script/issues/2779 . Last meanigingful comment was from jwalton, a month ago.
Still, it doesn't seem rocket science to add support for it, so it will probably come soon.
Michael Ficarra (creator of CoffeeScript Redux) suggested using https://github.com/michaelficarra/commonjs-everywhere .
Two caveats:
It only works for bundling CommonJS modules.
It uses CoffeeScript Redux, which is still in beta (although working quite well it seems), and not 100% compatible with original CoffeeScript compiler.
So this does not work for what you ask for specifically, "concatenation".
Added April 14
You might have luck with these: combine-source-map and/or generate-sourcemap, both by same author.
Added April 26
This looks really simple: https://npmjs.org/package/mapcat . You just have to feed it the individual source map files generated by the coffee compiler.
Added May 16
Mariusz Nowak has just released webmake-coffee. Like CommonJS Everywhere, it requires code to be organized as CommonJS modules. Unlike CommonJS everywhere, it uses regular CoffeeScript.
It also seems the Grunt Coffee-Script plugin has had source-map support for concatenated files for quite a while (two months), effectively proving my original answer to be incorrect.
The upcoming version 2.0 of Snockets will have support for it too.
I ended up going with browserify using coffeeify as the transform option, and enabling browserify's debug option. I bundle up the app on each request for my main.js file, and any runtime errors show up in my original source with pretty decent accuracy.
Sure beats mapping runtime errors in the concatenated/compiled js back to the coffee source with my eyeballs!
I needed to annotate AngularJS code before minification, but grunt-ng-annotate didn't accept input source maps, thus I would not be able to use maps generated by the CoffeeScript compiler.
Apparently, with gulp-sourcemaps this is not an issue:
var gulp = require('gulp');
var $ = require('gulp-load-plugins')(); // loading gulp plugins lazily
// remember to include them in the package.json
gulp.task('appJS', function() {
// concatenate compiled .coffee files and js files into build/app.js
gulp.src(['./app/**/*.js','./app/**/*.coffee'])
.pipe($.sourcemaps.init())
.pipe($['if'](/[.]coffee$/, $.coffee({bare: true}).on('error', $.util.log)))
.pipe($.concat('app.js'))
.pipe($.ngAnnotate())
.pipe($.uglify())
.pipe($.sourcemaps.write())
.pipe(gulp.dest('./build'))
});
The same approach works in other situations, too. In my case, this is the only approach that worked.
I have written a grunt task that does this flawless. Check it out
I have a directory like below:
/folder/b.js
/folder/jQuery.js
/folder/a.js
/folder/sub/c.js
I want to minify all these js files in one js file in order:
jQuery.js -> a.js -> b.js -> c.js
Q:
1.How can I do it via grunt-contrib-uglify?(In fact, there are lots of files, it is impractical to specify all source filepaths individually)
2.btw, How can I get unminified files when debug and get minified single file when release and no need to change script tag in html(and how to write the script tag)?
Good questions!
1) Uglify will reorder the functions in the destination file so that function definitions are on top and function execution on bottom but it seems that it will preserve the order of the function executions.
This means that the function jQuery runs to define its global functions will be put first if you make sure jQuery is mentioned first in Uglify's config in the Gruntfile.
I use this config:
uglify: {
options: {
sourceMap: true
},
build: {
files: {
'public/all.min.js': ['public/js/vendor/jquery-1.10.2.min.js', 'public/js/*.js'],
}
}
}
2) I don't think there is one definite way to accomplish this. It depends on what web framework, templating framework and what kind of requirements you have. I use express + jade and in my main jade layout I have:
if process.env.NODE_ENV === 'production'
script(src='/all.min.js')
else
script(src='/js/vendor/jquery-1.10.2.min.js')
script(src='/js/someScript.js')
script(src='/js/otherScript.js')
In my package.json I have:
"scripts": {
"postinstall": "grunt"
},
This means that when I run npm install on deploy (on Heroku) grunt is run to minify/concat files and when the app is started with NODE_ENV=production the minified client side javascript is used. Locally I get served the original client side javascripts for easy debugging.
The two downsides are:
I have to keep the two lists of script files in sync (in the Gruntfile and in the layout.js) I solve this by using *.js in the Gruntfile but this may not suite everyone. You could put the list of javascripts in the Gruntfile and create a jade-template from this but it seems overkill for most projects.
If you don't trust your Grunt config you basically have to test running the application using NODE_ENV=production locally to verify that the minification worked the way you intended.
This can be done using the following Grunt tasks:
https://github.com/gruntjs/grunt-contrib-concat concatenates
files
https://github.com/gruntjs/grunt-contrib-uglify minifies
concatenated files
EDIT
I usually run all my files through a Grunt concatenation task using grunt-contrib-concat. Then I have another task to uglify the concatenated file using grunt-contrib-uglify.
You're probably not going to like this, but the best way is to define your js source files as AMD modules and use Requirejs to manage the order in which they load. The grunt-contrib-requirejs task will recurse your dependency tree and concatenate the js files in the necessary order into one big js file. You will then use uglify (actually r.js has uglify built-in) to minify the big file.
https://github.com/danheberden/yeoman-generator-requirejs has a good example gruntfile and template js files to work from.
EDIT
I've recently started using CommonJS modules instead of AMD since it's much closer to the ES6 module spec. You can achieve the same results (1 big complied+concatenated js file) by running commonjs modules through Browserify. There are plugins for both grunt and gulp to manage the task for you.
EDIT
I'd like to add that if your site is written using ES6 that Rollup is the best new concatenating package. In addition to bundling your files, it will also perform tree shaking, removing parts of libraries you use if included via an import statement. This reduces your codebase to just what you need without the bloat of code you'll never use.
I don't think you can do this with the uglify task alone, but you have a multitude of choices which might lead to your desired outcome.
A possible workflow would be first concatenating (grunt-contrib-concat) the files in order into one single file, and put this concatenated file through uglify. You can either define the order for concat in your Gruntfile, or you use on of those plugins:
First one would be https://github.com/yeoman/grunt-usemin, where you can specify the order in your HTML file, put some comments around your script block. The Google guys made it and it's pretty sweet to use.
Second one would be https://github.com/trek/grunt-neuter, where you can define some dependencies with require, but without the bulk of require.js. It requires changes in your JS code, so might not like it. I'd go with option one.
I ran into the same issue. A quick fix is just to change the filenames - I used 1.jquery.min.js, 2.bootstrap.min.js, etc.
This might be only remotely related to your question but I wanted something similar. Only my order was important in the following way:
I was loading all vendor files (angular, jquery, and their respective related plugins) with a wildcard (['vendor/**/*.js']). But some plugins had names that made them load before angular and jquery. A solution is to manually load them first.
['vendor/angular.js', 'vendor/jquery.js', 'vendor/**/*.js]
Luckily angular and jquery handle being loaded twice well enough. Edit: Although it's not really the best practice to load such large libraries twice, causing your minified file unnecessary bloat. (thanks #Kano for pointing this out!)
Another issue was client-js the order was important in a way that it required the main app file to be loaded last, after all its dependencies have been loaded. Solution to that was to exclude and then include:
['app/**/*.js', '!app/app.js', 'app/app.js']
This prevents app.js from being loaded along with all the other files, and only then includes it at the end.
Looks like the second part of your question is still unanswered. But let me try one by one.
Firstly you can join and uglify a large number of js files into one as explained by the concat answer earlier. It should also be possible to use https://github.com/gruntjs/grunt-contrib-uglify because it does seem to have wildcards. You may have to experiment with 'expand = true' option and wildcards. That takes care of your first question.
For the second part, say you joined and uglified into big-ugly.js
Now in your html you can add following directives:
<!-- build:js:dist big-ugly.js -->
<script src="js1.js"></script>
<script src="js2.js"></script>
<!-- etc etc -->
<script src="js100.js"></script>
<!-- /build -->
And then pass it through the grunt html preprocessor at https://www.npmjs.com/package/grunt-processhtml as part of your grunt jobs.
This preprocessor will replace the entire block with
<script src="big-ugly.js"></script>
Which means that the html file with be semantically equivalent - before and after the grunt jobs; i.e. if the page works correctly in the native form (for debugging) - then the transformed page must work correctly after the grunt - without requiring you to manually change any tags.
This was #1469's answer but he didn't make it clear why this works. Use concat to put all js files into one, this module does this in the order of file names, so I put a prefix to the file names based on orders. I believe it even has other options for ordering.
concat: {
js: {
options: {
block: true,
line: true,
stripBanners: true
},
files: {
'library/dist/js/scripts.js' : 'library/js/*.js',
}
}
},
Then use uglify to create the minified ugly version:
uglify: {
dist: {
files: {
'library/dist/js/scripts.min.js': [
'library/js/scripts.js'
]
},
options: {
}
}
},
If your problem was that you had vendors which needed to be loaded in order (let's say jquery before any jquery plugins). I solved it by putting jquery in its own folder called '!jquery', effectively putting it on top of the stack.
Then I just used concat as you normally would:
concat: {
options: {
separator: ';',
},
build: {
files: [
{
src: ['js/vendor/**/*.js', 'js/main.min.js'],
dest: 'js/global.min.js'
}
]
}
},
I want to use the google closure compiler on the javascript source we're using.
In development mode we tend to break functionality to lots of files but for production would like to have them combined into modules.
When calling the compiler I can give it a list of files to include for compilation, but the output of that shows that the compiler did not save the order of the files list.
I searched about it and found that I can use goog.provide/good.require in order to control the dependencies between the different js files.
The problem with that is that it adds code to my js which I just don't need or want, for example:
goog.provide("mainFile")
will add this:
var mainFile = {};
to the compiled js file, something that I don't want.
We're not using the google closure library at all, all I want to use is the compiler.
Is there a way to tell the compiler the order of the files without including more "closure library" functionality which I have no need for?
I can of course create a tool of my own which will first take all the files, combine them into one which will then be the input of the compiler, but I would prefer to void that if it can be done by the compiler itself.
Edit
The goal is to be able to produce modules like the answer in this thread: Using the --module option in Closure Compiler to create multiple output files
And so I want to add to that the ability to control which files go into which module while also having control on their order.
For now I don't use wildcards, but I plan to do so in the future (if it's possible).
simply "cat file1.js file2.js > combined.js && compile..." is fine, but in our case it's a bit more complicated and we'll have to write a program/script that does that based on some logic.
If we can somehow tell the compiler the order of the files in advanced it might just save the time of implementing such a program.
Thanks.
Closure-compiler's ability to create multiple output files provides a powerful tool to separate input files into distinct output chunks. It is designed such that different chunks can be loaded at differing times depending on the features required. There are multiple compiler flags pertaining to chunks.
Each use of the --chunk flag describes an output file and it's dependencies. Each chunk flag follows the following syntax:
--js inputfile.js
--chunk name:num_files:dependency
The resulting output file will be name.js and includes the files specified by the preceding --js flag(s).
The dependency option is what you will be most interested in. It specifies what the parent chunk is. The chunk options must describe a valid dependency tree (you must have a base chunk).
Here's an example:
--js commonfunctions.js
--chunk common:1
--js page1functions.js
--js page1events.js
--chunk page1:2:common
--js page2function.js
--chunk page2:1:common
--js page1addons.js
--chunk page1addons:1:page1
In this case, you are telling the compiler that the page1 and page2 chunks depend on the common chunk and that the page1addons chunk depends on the page1 chunk.
Keep in mind that the compiler can and does move code from one chunk into other chunk output files if it determines that it is only used by that chunk.
None of this requires closure-library or the use of goog.require/provide calls nor does it add any code to your output. If you want the compiler to determine dependencies automatically or to be able to manage those dependencies for you, you'll need to use a module format such as CommonJS, ES2015 modules or goog.require/provide/module calls.
Update Note: Prior to the 20180610 version, the chunk flags were named module. They were renamed to reduce confusion with proper JS modules. The answer has been updated to reflect the new names.
Update Note 2: There is now a utility to automatically calculate and generate these flags for you: https://github.com/ChadKillingsworth/closure-calculate-chunks
You can also set the output path, for example with:
--module_output_path_prefix ./public/js/
See also:
Using the --module option in Closure Compiler to create multiple output files