We are about to write a compojure app with AngularJS as the front-end framework.
Should we be writing the views and partials in hiccup ?
These are going to be static pages and templates and I don't see any major benefit in doing so.
Should we have the API in CLojure only and keep Angular templates in regular HTML?
If using angular you shouldn't be using hiccup on the server to render views and partials.
With angular you can treat your clojure app as an api server, rendering with hiccup would only waste resources, just serve those resources static.
There is a complete application using angular and clojure here which you can use as guide, github repo here
Related
I am learning MEAN Stack. I started from learning Angular(from angular.io) now I am learning node.js and express.js
My question is, if there is angular for front end in MEAN Stack then why there are views and template engines in express.js at back-end? Are they alternative for each other or complements each other? what is the boundary for the role and responsibility of these two?
I am looking forward for someone's help in clarifying of my concept for role these two technologies(express' views and angular) used in mean stack.
In order to answer your question, let me explain what is angular and what are template engines in express?
What is Angular?
Angular is a platform that makes it easy to build applications with the web. Angular combines declarative templates, dependency injection, end to end tooling, and integrated best practices to solve development challenges. Angular empowers developers to build applications that live on the web, mobile, or the desktop.
what is template engine?
A template engine enables you to use static template files in your application. At runtime, the template engine replaces variables in a template file with actual values and transforms the template into an HTML file sent to the client. This approach makes it easier to design an HTML page.
Some popular template engines that work with Express are Pug, Mustache, and EJS. The Express application generator uses Jade as its default, but it also supports several others.
So,
Angular is a framework with a templating component baked in. You use it to create Single page Web Applications which means that DOM modification is happening on the client side and the app exchange with server only data. If your concern is template it is plain HTML.
Whereas, template engines' rendered views are sent to client each time by server whenever request is made each time a new page is rendered on server and sent to the client which is Great for static sites but not for rich site interactions.
If there is angular for front-end in MEAN Stack then why there are views and template engines in express.js at back-end?
This is because not every time generating views from angular is recommended sometimes it is better to use Template Engines to generate views and send the rendered page to a client, generating views at client side has its own pros and cons and generating views at server side has its own.
Generating views using template engines (i.e. at server-side):
pros:
Search engines can crawl the site for better SEO.
The initial page load is faster.
Great for static sites.
cons:
Frequent server requests.
An overall slow page rendering.
Full page reloads.
Non-rich site interactions.
Generating views using angular engines (i.e. at client-side):
pros:
Rich site interactions
Fast website rendering after the initial load.
Great for web applications.
Robust selection of JavaScript libraries.
cons:
Low SEO if not implemented correctly.
The initial load might require more time.
In most cases, requires an external library.
So, after knowing the pros and cons, you yourself can better decide that in particular case which one is better for you. Mean Stack has provided options for developers.
As far as your question regarding the role of these two technologies is concerned, Angular is a lot more view generator only, It has features like routing, it as services two-way data binding etc while the template engines are meant to render HTML so that it can be sent to the client.
I hope you will find this answer useful.
References:
what is the template engine?
what is angular?
pros/cons
Angular is a full-fledged front-end framework that comes with its own way of doing templating, using angular-specific markup in your HTML. If you use Angular as your framework, you're more or less stuck with their way of templating within the Angular portion of your application.
Angular Features
It is a framework written in Javascript language
Manages state of models
Integrates with other UI tools
Manipulates DOM
Allows writing custom HTML codes
It is meant for javascript developers to create dynamic web pages in a quick time
NodeJS
It serves the web
It is runtime built on javascript engine in google chrome
It can be considered as a lightweight server which can serve client requests in a more
simpler way than java does
It performs communication operation with databases, web-sockets,
middleware etc.
Why we use angular for Tempting not Express/Node tempting Engine
Server-side rendering is the most common method for displaying information onto the screen. It works by converting HTML files in the server into usable information for the browser.
Whenever you visit a website, your browser makes a request to the server that contains the contents of the website. The request usually only takes a few milliseconds, but that ultimately depends on a multitude of factors:
Your internet speed
how many users are trying to access the site and
how optimized the website is, to name a few
Once the request is done processing, your browser gets back the fully rendered HTML and displays it on the screen. If you then decide to visit a different page on the website, your browser will once again make another request for the new information. This will occur each and every time you visit a page that your browser does not have a cached version of.
It doesn’t matter if the new page only has a few items that are different than the current page, the browser will ask for the entire new page and will re-render everything from the ground up.
How client-side rendering works
When developers talk about client-side rendering, they’re talking about rendering content in the browser using JavaScript. So instead of getting all of the content from the HTML document itself, you are getting a bare-bones HTML document with a JavaScript file that will render the rest of the site using the browser.
This is a relatively new approach to rendering websites, and it didn't really become popular until JavaScript libraries started incorporating it into their style of development.
See Examples HerePratical Example
Basically template engines in Express are mostly used for displaying 404 and other server error messages. I find them ideal for such use cases. Using template engines for complex front end rendering is bad and not a good practice.
Express JS is a web framework on top of nodejs http module. Whereas Angular JS is a front end framework which doesnot depend on NodeJs server to run. Conceptually both are similar in few features like routing whereas implementation is different
I am new to AngularJS and need some advice on how to structure a SPA with Web API for an external search application
Di I have to use
•MVC / razor views (leave all routing and rendering to Angular)? or just use 1 VS2015 app [use angularjs SPA template for VS2015 or just an empty web application with angular file and a webapi project under same solution?
any examples would be helpful to understand
For angular structure I am reading Google best practice and John Papa
Well, I think what you ran into now. I can suggest two of the ways you can choose.
If you want to keep your backend and frontend together you can go for angularjs SPA template for VS2015. It would come with the build pipelines, bundles and everything you'd need. Now you can choose to render your single page of angular to be rendered with a MVC razor view (if you want to have any mechanisms where you'd want to include your dependencies through the razor view) or just go with a blank html and web api controllers on the back. But you'd end up using one environment for all and I think that's best if you're building the full project.
Now, for the other way around, you can start with an web api project. You can instantiate your angular project with it or somewhere else. You can use yeoman or any scaffolding tool you like and use your own JS toolings you'd like to use. You can do the same in the VS project too but this approach is better if you want to keep the frontend and backend flavor separate.
And I'd suggest using typescript too.
I am new to AngularJS.I have two questions.
Is it possible to use JSP pages instead of HTML in AngularJS.
Is it possible to create a web application using AngularJS without webservices (for fetching data from DB) and use HTTP servlet for that purpose
Is it possible to use JSP pages instead of HTML in AngularJS.
Even if you use JSP the final output will be HTML so you can use JSP in AngularJS but JSP files are mainly used to render the frontend with data that you can do using HTML only in AngularJS.
Is it possible to create a web application using AngularJS without web services (for fetching data from DB) and use HTTP servlet for that purpose
Whether you use plain Servlet or any framework that creates REST APIs, it will be HTTP calls only.
(This is a newbie question which applies equally to all front-end MVVM frameworks. I'll answer it for the general good.)
AngularJS is a front-end framework which runs in the browser. It relies on a server delivering the content (HTML templates, CSS and JS sources) to the browser.
What you use as a server, is entirely up to you. It depends on whether you need server-side dynamic content.
If none is required in that area, you can use a static HTTP server like LightHTTP, or plain old apache, or nginx, or anything else to deliver the AngularJS site to the browser.
But in most you will have some server interaction (i.e. storing / querying stuff in a database, or communication / synchronization with other users, etc). The common approach for that is to deliver HTML/CSS/JS statically and add a bunch of REST interfaces. Flask and Tornado are popular server choices for that, or stuff like spray.IO / akka.http for higher traffic volumes.
In specific cases, you may want to work with pre-rendered HTML templates (usually because you want to dynamically exclude parts of pages for security/user role reasons). Then you need a server-side framework with template rendering. Django, JSP, ASP, pick your favourite.
It seems like you are asking how to use AngularJs in a JavaEE application. And yes it is possible. Only your index.jsp will be in jsp, and all you other views will be in html.
You can then use http requests to fetch data through your servlets.
it can be useful. here are scenarios:
you want to save ram, cpu for mobile phones or machines that doesn't have lots of power. you can partially render page in jsp and keep only minimal in angular.
your team is traditionally jsp heavy and you want to use them and gradually transfer to angular. eg... for i18n rendering jsp seems far better. note that i18n may not add lots of values in angular and you may not want to throw up existing code in jsp.
I have been noticing strong views in stackoverflow and they seem to dismiss everything that doesn't fit in their utopian all new cutting edge. all the angular projects I worked had heavy dose of legacy pages using jsp and it doesn't make sense to rewrite everything from scratch or lay off whole team and start hiring from scratch. and thus, yes, jsp makes sense with angular.
I am planning to develop my monitoring/dashboard pages for hardware devices like Cisco router/switch/controller using Angular JS Library.
My page contains graphs(line & area), Google maps, tables and some blocks (div with value)
Is it feasible to use Angular for monitoring data?
What are the advantages we can get by using Angular? since it is only monitoring we don't have to use 2 way binding.
I am looking for few points to justify why we need angularJS for monitoring/dashboard kind of pages rather than JQuery/Javascript.
Please let me know your thoughts and comments.
Thanks.
Using AngularJS is totally feasible.
Main advantages is that charts can be implemented as reusable components (AngularJS directives).
There is a project in development that allows building dashboard from arbitrary directives
Running Demo http://nickholub.github.io/angular-dashboard-app
Demo source code https://github.com/nickholub/angular-dashboard-app
Dashboard directive itself https://github.com/nickholub/angular-ui-dashboard
And here is example of visualizing data coming from WebSocket
https://github.com/nickholub/angular-real-time-charts
If your site is 100% static - and by that I mean that you do a request for a status page, and the page you get will never change before you do a new request - then angular might be a little unnecessary.
But if you want your status page to 'live', you could use socket.io to push new events and data to the client and let angular take care of the ui refresh.
There are some angular directives to work with graphs, but I have no experience using them.
Some pointers:
Node.js + socket.io + angular.js:
http://www.html5rocks.com/en/tutorials/frameworks/angular-websockets/
angular.js + charts: http://ngmodules.org/tags/charts
I have individual pages and initially I wanted to use angularJS because of data binding and the many other neat features. I also ended up using requireJS simply to help me manage my dependancies better as the list of javascript libraries I'm using is growing.
My question is using AngularJS with requireJS a no no for non single page web apps?
It's not a no-no. You can definitely use angular on non-single page apps. You just will lose a lot of the functionality - ie the stuff between "pages". You app will essentially be recreated on every page.
I've used angular for a multi-page site (basically a product search engine), with each page being separate. I used GET and POST to transfer stuff across pages, but ultimately, I wanted to use angular for rendering the content on the page because it's just neat and clean.