Here is what I intend to build:
There is a service providing data with RESTful JSON-only API. The server setup is Python + Flask.
There are several clients making use of this API, like a normal web app, mobile-compatible client and a Facebook App.
Now, my assumptions/decisions:
I decided on the server providing only data through JSON, thus handing over the presentation completely to the client-side.
I desire to make the web app mobile compatible, thus eliminating need of a separate mobile client.
Also, for Facebook app, I decided to use Facebook Canvas, which would render parts of the normal web app, thus reusing the code.
Feel free to correct me if anything is wrong in above assumptions. Though the above is theoretically possible, I would like to know if the practical implementation is feasible or not.
Now, the web app, after having fetched the base page/template from server, will have to handle the rendering dynamically after fetching data through JSON API. The data is quite simple: multiple-option questions, answering which user receives another question. At the end, user can share the result or invite other users.
With this setup, do I need a framework like angularjs or jQuery would suffice?
My main concern here is how do I handle internationalization? I initially intended to user Flask-Babel to internationalize HTML templates. But having zeroed in on JSON-only API, I don't have a clue as to how/where I handle it now: on client-side or server-side? What are the tools I use for it?
One approach I could think of was to have data in different languages on server itself, and send the JSON response with data in appropriate language, depending on some attribute the client sends in request.
Another approach is to let client do all the translation for a common dataset that server sends. I am not sure of this approach though.
You could find this plugin really helpful.
As far as the usage , it is quite simple to set it up for a single page application that is powered by a JSON API.
If we take a look at a sample usage :
HTML:
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript" src="[PATH]/jquery.js" /> // optional
<script type="text/javascript" src="[PATH]/i18next.js" />
</head>
<body>
<ul class="nav">
<li></li>
<li></li>
<li></li>
</ul>
</body>
Json (loaded resource):
{
"app": {
"name": "i18next"
},
"nav": {
"home": "Home",
"page1": "Page One",
"page2": "Page Two"
}
}
JS:
i18n.init(function(t) {
// translate nav
$(".nav").i18n();
// programatical access
var appName = t("app.name");
});
https://github.com/wikimedia/jquery.i18n may be close match. It can handle a lot of languages and messages are in json files and it is complete client side library.
If all of your interface code lives on the client side, so should your i18n. You would use a i18n library that works with the JavaScript framework you are using. For angular, that might be angular-gettext.
If you are developing several client you might use different i18n libraries in different client applications. Try to make sure they all compile gettext .po files – it will make it easier for your translators.
Using jQuery, Angular, etc. is a decision you should make based on your comfort with the technology, the needs of your application, and compatibility with the Facebook Canvas approach. Angular has powerful data binding, but it requires a mind shift compared to jQuery, for instance, so I suggest poking around with each to see if they meet your needs.
As for internationalization, you can use a plugin like jQuery.i18n, or you could roll your own, something I have done with jQuery and jQuery.Mustache for templating. The short version is that you use HTML templates to store your layout, then render them from inside jQuery like so:
var data = {myLabel: 'Some label', myOtherLabel: 'Some Other Label'};
$("#myDiv")
.html( $.Mustache.render( "MyTemplateId", data ) );
in html template:
<script type="text/html" id="MyTemplateId">
<div>
<label for="myInput">{{MyLabel}}</label> <input name="myInput" id="myInput type="text"/>
<label for="myOtherInput">{{MyOtherLabel}}</label> <input name="myOtherInput" id="myOtherInput type="text"/>
</div>
and on your page layout:
<div id="myDiv>
<!-- dynamic content inserted here -->
</div>
You use a loader command with jQuery.Mustache (https://github.com/jonnyreeves/jquery-Mustache) to load your templates from the server, and since you are using templates, you can fill in your values based on user language selection. How you store your internationalized data is dependent on your app. As Michael suggested, if it is a small amount of static content, maybe you just store it all in your JS files as constants and load into your Mustache render() methods as needed. If you have a larger amount/dynamic multilingual content, you should probably store it on the server and load it dynamically. One consideration is the number of languages you plan to support. If you go beyond a handful of languages, consider storing it on the server and loading language data on demand.
I like this approach because it gives you granular, runtime control over your layout and over internationalization. It also stores the data on the server but loads programatically from the client, maintaining a clean separation of concerns for your application layers.
As for responsive/mobile friendly design, using templating (Mustache) and checking the viewport at load time allows you to determine browser capabilities and serve the approrpriate layout without having to prompt the user to select a mobile/desktop experience.
If you go this route, you should also research script loaders like RequireJS and StealJS to handle dependency loading for your scripts, and to handle the initial browser check and layout generation.
Your question is too broad. I can only answer part of it and here are some of the answers:
I desire to make the web app mobile compatible, thus eliminating need of a separate mobile client.
In order to make sure that things are working fine you need to handle
Also, for Facebook app, I decided to use Facebook Canvas, which would render parts of the normal web app, thus reusing the code.
I am not sure.
With this setup, do I need a framework like angularjs or jQuery would suffice?
As you tagged that you are targeting this as a single page application. Therefore, I would recommend you to go for single page frameworks like Anglarjs, knockout.js or Node.js. A quick and good comparison between these frameworks can be found from here
Also this post shares how to implement Internationalization in Angularjs
My main concern here is how do I handle internationalization?
some of these frameworks provide support for handling internationalization and localization natively. For other you can find some links that will help you achieve internationalization.
Whereas if you use jQuery you will to define your own framework for handling single-page-application and apart for that you will need a huge bunch of add-on's to accomplish your objective.
Hope this helps!!!
Steps to implement i18n via js & json:
define css class for i18n tag, e.g. <span class="i18n" id="i18n_username"></span>
define i18n values for different language in different .properties file, e.g. in userhome_en_US.properties, there is a key value: username = Username
write backend API to load .properties file by language, and return in json key-value format, e.g. send param: lang=en_US, page=userhome to I18nAction -> loadI18n(), then it will return json value via ajax: {"username":"Username"},
write js function to load i18n key-value by lang & page param,
update i18n text on web page, by get the tag via css class, and replace content, e.g. use jquery to get all span tag that has class="i18n", then remove the i18n_ prefix of the id, then use it as key to get the value from returned json, then replace the content of span,
I did write util programs like this, it's quite flexible & easy to use. The basic concept is come from struts2 framework's i18n feature.
Although I don't know your technical constraints in detail, I believe it all depends on your volume of data :
If you have few "questions / answers" that probably won't evolve much over time, you can treat I18N as constants. Putting everything on the client side makes sense.
If you have a big amount of "questions / answers" that will probably evolve, I believe you have to treat I18N as data.
Since you have made a JSON API, the odds are that your Q/A is your data, and it already belongs to your server side.
The real question is : do you want to deliver a new version of your client app everytime you add or correct a question?
That's why I would do this :
One approach I could think of was to have data in different languages on server itself, and send the JSON response with data in appropriate language, depending on some attribute the client sends in request.
edit (precision) : I'm talking about the questions and answers. For the application messages (menus, text, help messages, etc), you should use your client framework's i18n components. The other answers provide a lot of good tools.
I load lot of JavaScript From My DB for validation and for Costume Validation which can be Uploaded through My Customer so i want to validate whether the given Javscript is valid or Not While Rendering it on my page i am using MVC 3.0 razer view engine
Please help me finding a way fix it
Thanks
Ashies
Your task is simply not recommended. Render JavaScript code directly from the database is dangerous because you are leaving the doors wide open to XSS attacks.
However, yes, you can validate JSCode normally with JSLint.
There is a plugin for visual studio, and of course there might be a way to use the functionality packed in the JSLint DLL so you can check your JavaScript.
This two posts might put you in the "right" direction. (I still have to say that rendering user entered JS code is fundamentally wrong)
http://www.codeproject.com/Articles/21438/JSLint-VS-JavaScript-Verifier-for-Visual-Studio
http://blog.outsharked.com/2011/08/sharplinter-command-line-tool-for.html
I assume that you are working with Visual Studio 2010/2012.
As Adrian Salazar said:
Your task is simply not recommended. Render JavaScript code directly from the database is dangerous because you are leaving the doors wide open to XSS attacks.
That being said I would highly recommend rethinking your current design. If you're planning on doing so, you should have a look at Web Essentials which is a plugin available from NuGet. This has JSHint integrated which will check your Javascript after saving a file or on building your application within Visual Studio.
Also downloadable as installer:
http://visualstudiogallery.msdn.microsoft.com/6ed4c78f-a23e-49ad-b5fd-369af0c2107f
or for 2012:
http://visualstudiogallery.msdn.microsoft.com/07d54d12-7133-4e15-becb-6f451ea3bea6
Javascript syntax checking is tricky because there is so much scope for generating silent run-time errors based on how primitive are handled (for example).
There are verifiers like JSLint available and you can build your own techniques for verification.
I use the following structure for javasript files (using jquery) setting a class ("scriptVerified") on the body tag if the script completely runs - which can quickly tell you if the script looks syntactically OK. But event handlers can still go wrong when the event is fired.
#AdiranSalazar's security warning is worth listening to.
$(document).ready(function () {
pageScript.Init();
});
var pageScript =
{
Init: function()
{
pageScript.CleanUp();
pageScript.RegisterHandlers();
pageScript.Start();
pageScript.Final();
},
CleanUp: function()
{
//put page cleanup stuff in here
},
RegisterHandlers: function()
{
//register event handlers in here
},
Start: function()
{
//put page js code in here
},
Final: function () {
$("body").addClass("scriptVerified"); //add class to body to say this has run
}
};
I am developing an extension for Mediawiki which is based on another extension (developed in-house) that will not work above with a Mediawiki installation with a version superior 1.16.5 . I need to include javascript in pages belonging to a specific namespace and I cannot use the ResourceLoader http://www.mediawiki.org/wiki/ResourceLoader .
Does someone know if there's a simple to do this? I need to include JQuery and Datatables for a custom rendering of the pages belonging to the namespace.
There are at least three ways to go about this.
The 1st approach is to edit the magic page MediaWiki:Common.js and add something like this:
if(wgNamespaceNumber == 0) { // NS_MAIN
importScript('MediaWiki:MyScript.js');
}
You can place arbitrary javascript in the block, the importScript bit there is for executing JavaScript stored in a Wiki page but there are other ways to include JS on the fly as well (see eg. this question). See Manual:Interface/JavaScript for details of the MediaWiki side of things.
The 2nd approach would be to hack the PHP that produces the MediaWiki page to inject <script> tags depending on the current namespace, but that's a bit more involved: you'd need to build a custom extension and hook it in at some appropriate point. The ParserAfterTidy hook looks suitable, see Hooks.
The 3rd approach would be to simply edit the skin and load the JS for every page in the wiki -- is there a reason you don't want to do this for every page? They're cached anyway, so it's only a one-time hit.
I'd like to build my own, but I'm not sure about the best way to do it. A partial is a template that is only a part of another bigger template and which can be inserted into multiple other templates at will.
Templating itself is fairly basic, just string exctraction and concatenation, but clientside partials have me a little stumped.
Here are a few methods I thought about:
1,
I could write a javascript helper function that loads partials through ajax into some form of local storage I suppose, and all subsequent templates that require that particular partial would first look inside local storage. I think this method isn't very safe because local storage isn't always guaranteed. And if I can't save them into local storage, partials would result in too many ajax calls.
2, I could put them all into script tags inside my main html file. This would work reasonably well, especially with head.js (to enable parallel loading of script tags), but still - I think each script tag is a separate call to the server right? That doesn't exactly improve the situation.
3, I could put all templates into a single script tag (or html I guess) and manually filter through some kind of delimiter...like: "#template1(blabla template1 string) #template2(blablabla template2 string) and put those strings into globals.
This would result only into a single call to the server, all the rest is done on the client.
Suggestions? I have looked at existing templating engines, but I can't really determine how they do it. The code is pretty complicated
The approach I took to spec out template calls and on-demand loads for the spec/rewrite of jQuery templates is to pipeline it.
See section 9 of the (early) draft spec, and see the conformance suite tests at the bottom for an example of custom on-demand template loading (Testcase "Main calls and Loaded just in time!" is the relevant one).
The basic gist is that plugin loaders (written in JS) get to hook in between-parsing and compiling to inspect the parse tree. A plugin pass gets an object mapping template names to parse trees. If they see any partial template selectors (to use your parlance) they can try and load any unresolved templates using AJAX calls or file I/O on Node.js, and add the partials to the input object to cause the compiler to compile the just loaded partials along with the public templates.
Efficiency-wise, see the benchmarks. I'm in the process of migrating the code to github : https://github.com/mikesamuel/jquery-jquery-tmpl-proposal in case you want to collaborate.
When building webapps with MVC web framworks like Django, Kohana, Rails and the like, I put together the application without JS-driven components initially, and then add them afterwards as "improvements" to the UI.
This approach leads to non-intrusive JS, but I don't have a good "standard" way of how to go about organizing the JS work. Most of the JS I write in apps like these are 10-30 line JQuery snippets that hook into some very specific part of the UI.
So far I often end up inlining these things together with the part of the UI they manage. This makes me feel dirty, I'd like to keep the JS code as organized as the python / php / ruby code, I'd like for it to be testable and I'd like for it to be reusable.
What is the best way to go about organizing JS code in a setup like this, where we're not building a full-blown JS client app, and the main meat is still server side?
I am also very interested in what other people have to say about this. The approach I've taken is to use object literal notation to store the bulk of the function, and store these in one file included on all pages (the library)
uiHelper = {
inputDefault:function(defaulttext){
// function to swap default text into input elements
},
loadSubSection:function(url){
// loads new page using ajax instead of refreshing page
},
makeSortable:function(){
// apply jQuery UI sortable properties to list and remove non javascript controls
}
}
Then I include a .js file on any page that needs to use the library that ties the elements on that page to the function in the library. I've tried to make each function as reuseable as possible and sometimes the event binding function on the page calls several of my library functions.
$(document).ready(function(){
$('#mybutton').live('click',uiHelper.loadSubSection);
//more complicated helper
$('#myotherbutton').live('click',function(){
uiHelper.doThisThing;
uiHelper.andThisThing;
});
});
edit: using jsDoc http://jsdoc.sourceforge.net/ notation for commenting for these functions can produce documentation for the 'library' and helps keep your code easy to read (functions split by comments).
The following question is along similar lines to your own - you should check it out...
Commonly accepted best practices around code organization in JavaScript
When dealing with JS code, you should first analyze whether it will be used right away when the page loads. If it's not used right away (meaning the user must do something to invoke it) you should package this into a JS file and include it later so the load time is perceived faster for the user. This means that anything that the user will sees should go first and JS related to the functionality should be imported near the end of the file.
Download this tool to analyze your website: http://getfirebug.com/
If the JS code is small enough, it should just be inline with the HTML.
Hope that helps a bit.
For quick little user interface things like that I put everything into a single javascript file that I include on every page. Then in the javascript file I check what exists on the page and run code accordingly. I might have this in UIMagic.js for example. I have jQuery, so excuse those jQuery-isms if they aren't familiar to you.
function setupMenuHover() {
if ($("li.menu").length) { // The page has a menu
$("li.menu").hover(function() { ... }, function() { ... });
}
}
$(setupMenuHover);
function setupFacebookWizbang() {
if (typeof FB != "undefined") { // The page has Facebook's Javascript API
...
}
}
$(setupFacebookWizbang);
I've found this to be a sane enough approach.
My preferred method is to store inline javascript in it's own file (so that I can edit it easily with syntax highlighting etc.), and then include it on the page by loading the contents directly:
'<script type="text/javascript">'+open('~/js/page-inline.js').read()+'</script>'
This may not perform well though, unless your templating library can cache this sort of thing.
With Django you might be able to just include the js file:
<script type="text/javascript">
{% include "js/page-inline.js" %}
</script>
Not sure if that caches the output.
If you are still worried about being 'dirty', then you could check out the following projects, which try to bridge the server/client side language mismatch:
http://pyjs.org/ (Python generating JavaScript)
http://code.google.com/webtoolkit/ (Java generating JavaScript)
http://nodejs.org/ (JavaScript all the way!)