On a prestoshop ecommerce site I have some modules which use jQuery plugins. The problem is that i have a lot of file requests and YSlow recommends me to use fewer requests by unifying the .js files.
Can you give me an advice about how can I unify the files used by those modules(which are basicaly jQuery plugins)?
It's telling you to use pack multiple javascript files into one. This may or may not be neccesary depending on how you load your files.
If you use something like head.js which loads your files async after the page is loaded then your page won't be blocking whilst your loading so packing them together doesnt matter
Or you can use something like multi-part XHR which will combine them for you. Take a look at supply.js.
Another popular option is require.js (Havn't checked that website in a while. It looks pretty neat. Loving the layout)
If you using a lot of <script src="foo"> in your <head> tag well then that's not a good way to go about it.
Related
I have done my research on combining JS and CSS files. I am still a novice when it comes to all of this so the explanation like some of these minifies and compilers at Github and Google don't really make sense in normal English.
I have the following CSS files:
bootstrap
bootstrap-min
bootstrap-responsive
bootstrap-responsive-min
main
prettyPhoto
These are my JS files:
bootstrap
bootstrap.min
jquery
jquery.prettyPhoto
jquery-migrate-1.2.1
theme
Which tool should I use and if someone could explain step by step that would be great.
If you want to just have one big js and cs file then you can just combine them into ones by copying and pasting the content of each file one after another, in the same order you would include them on a page. Keep in mind that you do not need bootstrap if you are including bootstrap.min file after it. It's the same file, only the one with .min in name is minified version of it. Same goes for js files.
Then if you want... you can run a tool for compression like this one:
http://refresh-sf.com/yui/
and hope everything works fine.
Though combining files is easy that not something you should do to libraries. Moreover for most cases you should not merge these files.
Libraries tend to stay unchanged for long time, thus will be eventually cached by user. Site loading time will be faster.
A good approach is to link these libraries to 3rd party CDNs (Google, JQuery, etc.). They are far better with load balancing and this will increase your page loading time. (There could be some DNS lookup overhead, though).
Larger files tend to skip the cache. So having large file can make your page significantly slower if every next page call will download the library again.
Of course for your custom script joining in single file and minimization will almost always be recommended.
Coming from a C# background where every class is (best practices) stored in its own individual file, it makes development quite clean. I've never written anything complex in Javascript in the past, but I am starting to learn HTML 5 and I want to write a complex game using the HTML 5 canvas.
Putting all of my functions and code into a single .js file seems very messy. Is there a way to split it up, or a tool/IDE that lets you develop using separate files and compile them into a single one for deployment?
I guess I am looking for some best practice advice. Questions like this generally seem to get closed, so here are my specific questions to adhere to the SO FAQ that demands practical, answerable questions:
Does complex JS development usually involve all the code being in a single JS file? Eg. you're writing space invaders, do you just have spaceinvaders.js or do you have ships.js, logic.js etc.
Is it possible to split up your JS (whether using multiple script tags or pre-compiling to a single JS file) or to just put it all in a single file?
What's the industry standard? Does the HTML 5 spec make any recommendations?
There two possible ways.
Personally, I would use a build tool to simplify working with multiple files.
Using a build tool
Grunt
My favourite tool to keep up with complex js applications is grunt. With grunt you can develop in as many files as you want and use its plugins watch and concat to automatically concat them on save. You can do a lot more but this is the basic use case which may be helpful for you.
Grunt requires nodejs and takes some time to setup. But once you are ready with your Gruntfile setup it really speeds up your development process.
To make your project ready for production use you can also minify your scripts with some configuration and a single command.
A lot of the major javascript libraries are using grunt, easily recognizable based on their Gruntfile: jQuery, AngularJS, Twitter Bootstrap etc.
Grunt is also part of the development toolset yeoman.
Brunch
Brunch is another build tool which allows you to do similar things like grunt does.
Loading only the needed files
If you are developing a huge single page application and are concerned about the startup time of your application, one single file may not be the best solution. In this case you can use a javascript module loader.
Require.js
Therefor require.js is a goot fit. It allows you to only load the actual needed files on the current page. Though setting up require.js is a bit more work than setting up grunt.
Of course you can use more than one javascript file. How else would libraries like jQuery or Knockout function?
One thing to keep in mind, though, is that one of the things you want to do to keep your pages feeling snappy is to reduce the total number of http requests per page load. Adding a bunch of javascript files that are loaded separately causes an additonal request for each extra file. Therefore, you might want to experiment with a system for your build that stitches your javascript files together into a single item that you can use at deployment. There are a number of solutions out there that will do this for you in an automated way.
you could consider using requirejs - a very nice libray to split your javascript to modules.
it also provide a tool that you can "combine" all modules to a single file.
You can use as many javascript files as you want. Just add a link to them in your html code:
<body style="background-color: black" onload="main();" >
<!-- Your HTML body contents -->
<!-- Your scripts (here, I used HTML5 BoilerPlate to setup, and the links to jquery are provided) -->
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<script>window.jQuery || document.write('<script src="js/vendor/jquery-1.9.1.min.js"><\/script>')</script>
<script src="js/main.js"></script>
</body>
Then you can hookup your main.js to listen for the main() function call:
function main() {
//here you can do your basic setup or delegate the control of the app to a different .js file.
}
or the jQuery document ready callback:
$(document).ready(function() {
//here is a good spot to hookup other jQuery listeners
});
Im a bit clules on the following situation, i am building a site, and right now all my js functions are in one js file, yes i know its a very bad idea.
What i am unfamiliar with, when i was checking other sites, i saw they include jQuery in the header and in the footer, different scripts are loaded.
I am unfamiliar, and please be nice i am a bit of a beginner.
Do people use some kind of plugin for this? or they include every script manualy in the specified file at the buttom?
I would like to break the scripts to parts, and not to include everything in one file.
What i mean by this, some functions only required in the profile page, some in the settings, and some in the login.
If someone could please give me some info about this would really help me.
Thank you
That's the sort of thing that one would use RequireJS for.
http://requirejs.org/docs/start.html
It will allow you to setup dependencies for your different JS files. These dependencies would then be loaded as needed.
Do people use some kind of plugin for this? or they include every script manualy in the specified file at the buttom?
Well, usually websites are made in PHP from individual components. Think of it as bricks. Some of these bricks contain JS code. When they are put together you end up with some pages having unique parts of javascript code in different places. It's not particularly good, but can dramatically simplify and speed up development.
I would like to break the scripts to parts, and not to include everything in one file.
Usually you want to include your JS with <script> tags in website header. If for some reason you'd like to dynamically include external JS then you may try to use this simple function: include();
i am building a site, and right now all my js functions are in one js file, yes i know its a very bad idea.
It's bad from development point of view, but when it comes to deploying the website it's a very good habit as it can decrease loading time of your website (and the loading time is one of most essential things). There are even applications compiling multiple .js files into a single minified file in order to get best performance.
I have a template that has over 20 js/css files that it references to and of course this makes for a lot of http requests. I thought about stitching them together with php using minijs.php/mini.php but the problem Im seeing is the page seems to load slower when using minijs.php/mini.php. I used YSlow and just having each one linked individually it shows 3 seconds to load, when I use the minified solution it takes 7-10 seconds to load, even when cached. Does anyone recommend a better solution or do you even recommend combining them all together dynamically like this?
Yes, I do recommend combining the files and minifying them, ideally using either YUI Compressor, Google Closure Compiler, or, what jQuery recently switched to, UglifyJS.
As for a bit of how and why, read this and search Google for "why should I combine web site assets?".
Also bear in mind that this should be a preprocessing step, or at the very least something that is rendered once and cached and thereafter served by a static file server (Apache or Nginx, php should not be involved).
Check this python script.
http://github.com/hkasera/minify
It minifies js as well as css files too. It stores detailed log files and you can add this script as a git hook and save yourself from doing it manually everytime. I have created it during a project and it helped me a lot.
Hope it may help!
you can use many online tools which have features for compressing and combining multiple files.
for javascript compression you can use jsCompressor
and for css you can use CSS compressor CSSCompressor
Multiple sites reference combining JavaScript and CSS files to improve web page performance, including examples of using ANT build scripts to concatenate the files prior to deployment.
I've search, and haven't found any information how to automate updating references to those files in HTML and other documents. I am looking to avoid hacking together something error prone, and want to learn from others who have automated builds in the past.
Are there automated tools in the wild to complete this task that I'm not seeing? Are there recommended processes to update the script and link tags in HTML? Can these solutions be integrated with ANT or similar build tools?
There sure is and it's a smart thing to do.
I found a PHP solution, don't know it that's okay for you, but if it isn't you can still read it's source (it's not difficult) and learn a lot. The solution works like this:
Rewrite your requests like this: from css/main.css and css/skin.css to css/main.css,skin.css (of course you can put many more).
Use apache's mod_rewrite to redirect this request to a script (in our case combine.php), that will combine all files to a single one.
The script combines all the files and sends the combined file. Then it saves it to a cache folder.
Next time around it checks if there is an up-to-date version of the cache and serves that one. If the latest file modification time has changed, it discards the cache.
The solution works great and it even makes use of HTTP cache headers and spits out an [ETags], which you should do anyway.
You are correct this is a great way to speed up page loading. It will even work in conjunction with a CDN, which the other poster recommended.
Here is a small script that will pack multiple files in to one for deployment. It supports both JS and CSS, and will even "minify" them by removing whitespace, etc. Just hook this in to your build and deploy scripts.
juicer: http://cjohansen.no/en/ruby/juicer_a_css_and_javascript_packaging_tool
What even better, it will follow JS and CSS import statements, so you only need to point your HTML files to the loader file and it will work in both development and production. (Assuming you replace the loader file with the combined file on deployment.)
There are others, including some run-time solutions. But it sounds like you have a build process in place anyway.
As far as HTML updating, if you still need it, since automated deployments are very popular in the Ruby world, and you may find some standalone utilities to help even for non-ruby projects. (As above) Methinks this would be best handled by your own project's template language, though. (With a static resource revision id, or such.)
Good luck, and let us know what you find.
I think what you really want is a CDN Content Delivery Network.
Read about it here
http://developer.yahoo.com/performance/rules.html
http://en.wikipedia.org/wiki/Content_delivery_network