How to load angular controller and template in a single HTTP request? - javascript

I am using angularjs. want to load parts of a page that I package as "components", wherein a component contains its controller, template, directives and a few other assets like CSS etc. When needed, I want to load all of this on demand.
I was able to load the controller and the template on-demand by specifying a resolver for the controller and the templateUrl for the template. But is there any way I can combine them into a single HTTP request? Any examples?
Sorry forgot to add: I want to do it only on-demand, not precompiled/pre-aggregated (lets just say thats is a requirement thats been given to me). Is there a way?

You can use angular templatecache to add your html to a module and package template cache along with controller, services, directives etc.

In order to pull your Angular code and your html templates together in one request from the server, you'd need to have the templates combined in with your js. That would imply using some kind of job to process your html into js and concatenate it in with the rest of your code. Something like grunt-angular-templates might do the trick.
Edit
With the added requirement that this should be an on-demand sort of thing, I could only add (with the current information) that this sort of thing can be accomplished with bundling and request processing on the server, but the specifics on how to do this are totally dependent on your specific server stack. Often a server will have features that allow for on-demand resource bundling, or rendering of partial-views that might be helpful in this capacity.

Related

AngularJS make two applications with the same front end code

I'm working on two very similar projects (almost the same).
But the front end of the code is totally weak. I'm refactoring it and was thinking to use the most of the same code ( and specialize if there is a single rule for it ) for both applications and when generating the build on Grunt it generates the desired application...
I wonder if there is a more correct way to do this...
I would like to reuse as much JS and HTML as possible...
Angular JS is a framework, that perfectly divided the code into modules and make each module separate and reusable. Divide your code in modules. Each module having set of Controller, Service, Factory (REST API model), Directive (If any DOM Manipulation), Partials and CSS. Now you can use each Module separately. As in your case you have to use two different backends, make a rootScope property to determine which backend to use. According to the backend to be used configure your Base backend URL, Factories and Service and rest of directives, controllers, HTML and CSS remains the same.

Will I ever need to use ejs or layouts if I use Angular for frontend?

I'm currently using Sails for backend, which comes with an ejs view engine and a templating system which is rather neat. However, setting up Angular on the front end of things will get in the way of these functions.
For instance, I can no longer use templates, because if I have say <html ng-app="myApp"> inside layout.ejs Angular will never initialize.
Same thing should I include any ejs templates.
So what I have done now is created a index.html file inside my assets folder, turned off the Sails routes and layouts, and am purely working with Angular. This will do fine for my current project (except I can't make things as tidy as I'm used to, the boilerplate html need to sit there, etc.) but will it be a problem in other projects, I wonder?
In other words, what am I missing out on by not using ejs? How will I ever be able to get things from my Sails controllers into my views? Or won't I need to?
First this question is WIDE open to interpretation based on all sorts of variables.
If your using your APP simply as JSON delivering API, then in reality you don't need to use the template engine. So the basic premise of your question is valid.
However, their are still plenty of reaons to use the template engine.
For instance, you can still use EJS to setup your default layout and index page for your angular site.
For instance, I can no longer use templates, because if I have say inside layout.ejs Angular will never initialize.
This statement is completely wrong. I use server render templatse for my index page on a SPA in order to use my app version to point to updated assets and template files. That way old template files will not be cached when I update my app. Depending on the app the index page may be the only one to use the template engine as everything else will use static templates. Others I have the server render my templates using the template engine as well (for example: if I want to restrict certain aspects of my templates based on a user role.)
There are other reasons as well. You might try the Google Groups for sails as this is more of an open ended question.
https://groups.google.com/forum/#!forum/sailsjs
If you use Angular for frontend and SailsJs for the backend the best practice is to have two distinct applications which means you don't have use sails to render the views (No EJS mandatory ).
AFAIK SailsJS just need to be used as a REST API while Angular needs to render your views ( you could use http.post get put and delete to comunicate with your api).
Best Regards.
As sails.js is purely backend and Angular.js is purely frontend, they can work together nicely.
All you need to do is place your angular files and logic in
myapp/assets
folder. Assets folder is by default acessible on sails server url.
You can access it as http://localhost:1337/assets/file_name.
As for the ejs, if you are using any javascript framework like angular.js then it is not a requirement as all JSON api will be made in sails framework and angular will get data in JSON format.

How integrate cross-site multiple angular applications?

I have one big information system consisting of diferrent subsystems. One of my objectives is to organize navigation and localization between these subsystems.
When I was generating view in backend via JSP I simply used jsp:include referring to special web-app which returns header with cross-site navigation and also this web-app was responsible to store user locale for all subsystems.
Now I switched to angular and found out that it's impossible to replace jsp:include with ng-include. I have 2 different ng-apps - header (coming from outside web-app) and current, say, subsystem1 ng-app. ng-include directive in header doesn't work because I have to bootstrap it, but I can't bootstrap header ng-app because it is absent - I'm fetching it with ng-include. Vicious circle.
Now I see one way to solve my problem:
Fetch header markup in second ng-app (non-header, subsystem1's ng-app) via ajax call to special header-web-app. Then, insert incoming HTML to header via simple DOM manipulations and bootstrap it manually. Disadvantage is obvious - I will make DOM manipulations in subsystem ng-app but insert HTML outside it because 2 different ng-apps must not instersect or be nested. Is it OK?
Looks like I'm inventing bicycle, so I'm asking here, how integrate cross-site ng-apps? Is it possible to share data between different ng-apps in one web page? I know, that it's possible to share data between controllers via services and factories and this is good practice. Is there any angular-way to share data between ng-apps?
Please, do not provide JSP-like solutions as I want to keep angular way of development and thus make only static pages with angular markup and make all server side job via ajax calls. Probably, I misunderstood angular way but now I'm seeing it exactly as I describe.
Method #1 from this site looks good for me. In short, any ng-app consists of markup anf js. JS can be simply loaded by script src=... and many ng-apps can be used as a modules of one big root app. Markup can be loaded by ng-include.

BackboneJS with Codeigniter

I have an application build with Codeigniter and I want to use BackboneJS for my frontend. I already build an API so that I can use the returned JSON from my Database, so the only thing I need is to integrate Backbone in my Codeigniter setup. I have also already an Backbone application, where I created most of the Views I need. So, in my Backbone's index.php I have:
<script data-main="js/config" src="js/lib/requirejs/require.js"></script>
<script>
require(['config'], function(config) {
require(['app/mainpage']);
});
</script>
Also in my index.php, I have all the div's where my backbone views are rendered.
I would like to know, how I do integrate this in Codeigniter. My file/folder-structure in Codeigniter is the typical CI-setup:
- application
- config
- controllers
- models
- views
- assets
- css
- img
- system
index.php
.htaccess
So what is the best way to do this? Should I create an additional js-folder and then place my backbone-setup in that folder? If so, what about the <script>-code shown above? where to place it?
Thanks in advance
You asked this a while ago, so I don't know if you're still looking for an answer, but since I use a similar setup occasionally with AngularJS I suggest:
loading a view with all header contents as a layout. I use this layout
Load your front-end client JS inside an include in /application/views/site/header.php, see this repo for example
Once you have all the libraries loaded up you can then load each individual JS application (Angular uses Modules) or use a single application which loads partials (I assume backbone has this feature, as does Angular).
Oh also, a trap for the unweary: Codeigniter doesn't support JSON posts well, so RESTful APIs are not easy out of the box. If you need to receive JSON post data, the best I've found thus far is the utterly obtuse:
$phpArray = json_decode(file_get_contents('php://input'));

Very large single page application design problems

I am currently writing whats going to be a very, very large single page web/javascript application.
Technologies I am using are ASP.NET MVC4, jquery, knockout.js and amplify.js.
The problem I am having is that most if not all of the single page application examples are for smaller applications where having all of the script templates (be it jquery, handlbars, etc...) are all in the same file along with the rest of the html code. This is fine for smaller apps but the application I am building is an entire maintenance logistics application with many, many, many screens.
The approach I took so far is I have an outer shell (my main index.cshtml file) and I am using jquery's load() method to load or rather inject the particular file I need when a user makes a certain selection.
example:
function handleLoginClick(){
App.mainContentContainer.delegate('#btnLogin', 'click', function() {
App.loadModule('Home/ProductionControlMenu', App.MainMenuView.render());
});
}
here's the code for the App.loadModule function:
App.loadModule = function(path, callback){
App.mainContentContainer.load(App.siteRoot + path, callback);
};
All was going well until I needed to actually start interacting with the various form elements on the newly loaded screen. jquery can't seem to get a handle on them directly. I can't use .live() or .delegate() because they aren't events, they are textboxes and buttons and sometimes I need to change their css classes.
They only way I found is to get a handle on an element from the outer shell (something that wasn't loaded via .load() ) and use jquery's .find() method like so:
App.mainContentContainer.find('#btnLogin').addClass('disabled');
clearly I don't want to have to do something like this everytime I need to interact with or even retrieve values from a form element.
Does anybody have any ideas as to how I can create a maintainable very large single page application with potentially hundreds of .html files without having to have all that html code located in a single file and still get around this .load() issue I am having?
Any thoughts would be greatly appreciated. :-)
V/R
Chris
UPDATE
I thought I'd post an update and as to how things went and what worked. After much research I decided to go with Google's AngularJS Javascript framework. It simplified the ordeal exponentially and I would definitely, definitely advise all who are looking into making a large SPA to give it a look.
Links:
Main Site
http://angularjs.org/
Awesome free short videos on Angular:
http://www.egghead.io/
This is actually a very complicated question as it really gets down to the design of your architecture.
For large-scale single-page applications, it's best to use some sort of front-end MV* style framework such as backbone.js, which ties in to jQuery quite usefully. You should also think about using some sort of dependency management framework such as require.js in order to load your scripts and dependencies asynchronously, and even better -- use the AMD pattern in your application design to make your architecture modular and easier to manage.
As far as how this relates to your MVC4 project, you have some options:
Do you want to use MVC as a "service layer" of sorts, that simply returns JSON objects, allowing your front-end to do the markup/template creation (think handlebars.js), or
Do you want your MVC project to return partial views (HTML) as a response, where you leverage the Razor templating system and simply use the front end to display what comes back from the server?
Either way, you will have to devise a way to handle front-end events and navigation (backbone provides both of these things when coupled with jQuery). Even more complicated is the pattern you choose to notify one view of another view's activities (there are many ways to do this) -- a publish/subscribe pattern for example.
I hope I have helped a bit, I know I'm not fully answering the question, but the answer could get really long!
Lots of things are wrong with your approach. What I'd recommend is to watch some presentations on how people build Single Page Applications and what tooling is mostly used.
This seems like something reasonable: http://singlepageappbook.com/
You will at least want
some kind of modules system (I recommend AMD – http://requirejs.org)
an MV* framework (Backbone, Ember.js etc.)
DOM/AJAX Framework (jQuery, Mootools etc.). Some frameworks offer this and all of the above (Dojo, YUI, Sencha)
build solution (to have different environment in development / production)
Couple of good links:
http://nerds.airbnb.com/slides-and-video-from-spike-brehms-tech-talk
http://video.copenhagenjs.dk/video/3413395/simon-hjberg-swipely-building
http://backstage.soundcloud.com/2012/06/building-the-next-soundcloud/
http://www.youtube.com/watch?v=vXjVFPosQHw
If you don't need a complicated truly SOFEA Single Page App then I recommend you go the PJAX route.
Then you just write your app as a normal web 1.0 app with the performance benefits of a single page load. I urge you to consider this an option as it allows you to do most of your validation work server side.
The idea is very simple on every response your sending the whole page back minus the header and footer (which contains the javascript and css includes). DOM rendering time is incredible fast these days... whats not is a full page reload, So don't worry about the size of the HTML your returning back.
Also the "PJAX way" is much easier to cache, Google SEO friendly and is in fact what the new Basecamp does.
Note: Wanted this to be a comment not an answer but don't have enough exp to post comments ;(
[any corrections by community members welcome!]
Important points to consider for single page apps:
Lazy loading is vital as you don't want hundreds of js files loaded straight away as user first loads the page (very slow load time).
Good File organisation,- helps making changes easier, reduces complexity a bit and promotes reusable components. Makes testing of components easier.
Testing,- Since single page apps have a lot of javascript going on under the hood you would need a test framework for automatically testing components. This testing is on top of the tests you would use to confirm if certain user controls are rendered etc as you wouldn't want a viewless component making an ajax call to server when it shouldn't etc.
+1 for gryzzly's point about using a framework.
Sencha have a nice MVC like framework for their ExtJs product. They have data stores, ajax, lazy loading, class hierarchies and a lot more all bundled into the package. They have a good api page also to lookup object properties and methods (handy since there doesn't seem to be any intellisense for javascript :/ ). Their api page is; as far as I know, an example of a single page app. I know much of the stuff ExtJs does you can find an open source alternative but I like that it's just the one library and I don't have to download a couple of different frameworks to do various operations. [note: I have no affiliation to Sencha except for being a customer of theirs and like their stuff.]
Conclusion:
I'd say it would be quite difficult to manage a large single page app without using some client side framework; whether open source or not, and without using some architectural pattern like a client side MVC.
Single page apps I think are more complicated so your team would need to be quite handy at understanding the concept of a single page app and how to implement it. If you pull it off the site will be amazing in terms of user experience.
I would recommend to use Sammy.js and split various viewmodels in knockout to a separate url. And if you're using asp.net mvc 4, use partial views (user controls) so that you put all code in one file. And name all and split all js-code in a meaningful way, filename and namespace in js. That will help a lot in maintainability and your own sanity in the long run.
And use common sense!
The way I did it was to include javascript code related to the template along with the template itself. And then load the whole template+script thing using ajax. If you want to try this be warned that most browsers don't execute <script> tags injected into the page. Especially if done using innerHTML. As such you should eval the script tags yourself (alternatively you can use document.createElement to inject the script but this does not offer any additional advantages compared to eval since the browser will blindly execute the script anyway).
In my case, to make it easier to grab the html and script portions of the template I store my templates in XML files instead of plain old HTML. That way I can simply use .responseXML of the ajax request to parse the template. My template has the following basic structure:
<template options...>
<title>Optional</title>
<html><![CDATA[
Template body
]]></html>
<init><![CDATA[
// code that only needs to execute once
]]></init>
<script><![CDATA[
// code that needs to run every time
// the template loads
]]></script>
</template>
You also need to remember to configure your server to reply with the correct content type for you templates. Otherwise resultXML won't work. This is not the only way to implement this system of course. You could simply save your templates as HTML and then parse that HTML to extract scripts to execute.
The main bulk of your code, the functions, constructors, objects etc. can be included in a js file. The template script only need to call those functions to tell the rest of the page how to work with the template.
If you further separate your data from your template and only populate the template with data on the page or make a separate ajax request for JSON data then you can configure your server to make the browser cache your templates. This is especially useful for often used templates (such as templates for dialog boxes). This allows the browser to download the template only once and use the cached version the next time you call the template.
Anyway, that's how I did it last time. It scaled well enough to serve facebook users (the web app was a facebook app). Just sharing my experience. Hope it helps.
I've written a few huge single page application using Dojo Toolkit. I'm pretty sure whatever JavaScript framework you choose will probably work for you. I use Dojo because it provides me with features that makes huge single page application development easier to manage.
You can use Dojo's widget system to help you define all your screens and forms as widgets and then when you need them you can just instantiate and insert them wherever you need it. When ever you want to get rid of it, you can simply call destroy or destroyRecursive on that particular widget and its gone. Dojo's widget system also help you separate your HTML from your JavaScript, but still keep it together so that they are not located all over the place.
I've include a simple widget definition for a Login form.
This is the HTML template.
/* mine/forms/Login.html */
<div>
${form_name}
<label>Username</label>
<input data-dojo-type="dijit.form.TextBox"
data-dojo-attach-point="_usrfld" />
<br />
<label>Password</label>
<input data-dojo-type="dijit.form.TextBox"
data-dojo-props="type: 'password'"
data-dojo-attach-point="_pwdfld" />
<br />
<input data-dojo-type="dijit.form.Button"
data-dojo-props="label: 'Login'"
data-dojo-attach-event="onClick:_handleLogin" />
</div>
This is the JavaScript portion for the widget.
/* mine/forms/Login.js */
define([
"dojo/_base/declare",
"dijit/_Widget",
"dijit/_Templated",
"dijit/_WidgetsInTemplateMixin",
"dijit/form/Button",
"dijit/form/TextBox",
"dojo/text!./Login.html"
], function(
declare,
_Widget,
_Templated,
_WidgetsInTemplateMixin,
Button,
TextBox,
template
) {
return declare("mine.forms.Login", [_Widget, _Templated, _WidgetsInTemplateMixin], {
// assign the template
templateString: template,
// signal that we will have widgets within our template and the parser should
// locate them and instantiate them
widgetsInTemplate: true,
form_name: "My Login Form",
// place holders that will be referencing the corresponding widgets
// that I have placed a data-dojo-attach-point on
_usrfld: null,
_pwdfld: null,
_lgbtn: null,
// a call back function that will be trigger when the Login button is clicked
_handleLogin: function() {
var usr = this._usrfld.get('value');
var pwd = this._pwdfld.get('value');
// now you have the username & password
// you can use it to login
}
});
});
There are a few benefits that the widget system provides:
The HTML template will be loaded for you when needed
You can have widgets within widgets. Dojo takes care of instantiating and even destroying those widgets for you
You can use dojo's simple template language to help with inserting strings. The example above uses ${form_name}. If you want to use a more sophisticate facility dojo also supports a Django similar syntax templating language. This will allow you to use most of the tags available with Django like for, if-then-else, etc.
data-dojo-attach-point is very helpful. If you use this, you will never need to assign id to a DOM element anymore. You will not need to locate the element in your HTML DOM tree. The variable you name in data-dojo-attach-point will be auto assign to reference the widget or DOM element you have defined in your template. The example above uses the _usrfld, _pwdfld, and _lgbtn.
data-dojo-attach-event is also very helpful. If you use this, you will not have to manully add an event hook to the button, Dojo's widget system will hook it for you and will also clear the hook when your widget is destroyed.
If you use Dojo's build system, which is a system that takes all your JavaScript codes and compresses them, Dojo will replace your template with the actual HTML so that when you load your widget in production mode, Dojo doesn't have to make another AJAX request to grab your template.
These are just some of the features I use daily when I develop my projects. Hopefully it will provide you with some insight that you can use to make your decision when choosing the proper JavaScript framework for your project. As a side note, I'm not advocating Dojo or anything, just wanted to share what works for me.
To handle large size single page application it's recommended to break the individual module into different apps.
example : apps like search page app and result page app.

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