Sergheeva Yu.V.
National Mining University, Ukraine
The features of development modern web-applications
The Ruby on Rails framework
Modern
web-applications can be characterized as complicated software systems
development and maintenance of which is nontrivial task. Today web-application
frameworks are used extensively in developing web-applications such as a
corporate website, web portal or a web service. Web-application frameworks are
the basis for creating custom solutions; they provide the possibility to reuse
the components for solving common problems of web-applications. Nowadays such
frameworks as Zend (PHP), Symfony (PHP), Struts (Java) and Ruby on Rails (Ruby)
are used extensively by developers all around the world.
Ruby on
Rails is quickly becoming one of the most popular modern programming language
framework combinations. Rails' seamless integration into web servers and
databases and its elegant framework make a good choice for every programmer
wishing to develop the latest and greatest web applications.
Ruby on
Rails [3], often shortened to Rails or RoR, is an open source web application
framework for the Ruby programming language. Ruby is a dynamic, object-oriented programming language [2]. Ruby
supports multiple programming paradigms, including functional, object-oriented,
imperative and reflective. It also has a dynamic type system and automatic
memory management.
Like
many web frameworks Rails uses the Model-View-Controller (MVC) [5] architecture
pattern to organize application programming. Model-View-Controller architecture
is a programming pattern for separating data, business logic (which both
manipulates the data and interprets commands from the user), and presentation
(which displays the manipulated data). The Model View Controller principle
divides the work of an application into three separate, but closely cooperative
subsystems.
The
Model maintains the relationship between object and database and handles
validation, association, transactions, and more. This subsystem is implemented
in ActiveRecord library which provides an interface binding between the tables
in a relational database and the Ruby program code that manipulates database
records.
The
View is what the user see, in Rails terms that means the web pages that appear
in the browser. A presentation of data in a particular format triggered by a
controller's decision to present the data. They are script based on templating
systems like PHP, ASP, JSP, which are very easy to integrate with AJAX
technology. This subsystem is implemented in ActionView library. In Rails views
are written in a markup language, and by default that is ERb (Embedded Ruby).
The
Controller interacts with the Model and passes the required data into the
View. Updating, creating, and
destroying of database records are initiated in the controller. In addition,
controllers are responsible for selecting the appropriate view. This subsystem
is implemented in ActionController, which is a data broker sitting between
ActiveRecord and ActionView[1].
MVC architecture in Figure 1.
|
Figure 1: The Model-View-Controller Architecture [4] |
Ruby on
Rails is available for Linux, Windows, and MacOS X and can be installed on
various web servers such as Apache, LightSpeed and Lighttpd. Support for
FastCGI, SCGI, or Mongrel. Several database drivers exist for Ruby. Framework
Ruby on Rails maintains DBMSs, as Oracle, MySQL, Firebird, PostgreSQL and
Microsoft SQL Server. Overall, Ruby on Rails can be used with the popular
operating systems, web servers, and DBMSs.
Ruby on
Rails initially utilized lightweight SOAP for web services; this was later
replaced by RESTful web services.
Ruby on
Rails 3.0 uses a technique called Unobtrusive JavaScript to separate the
functionality (or logic) from the structure of the web page, and jQuery is fully
supported as a replacement for Prototype. Since version 2.0, Ruby on Rails by
default offers both HTML and XML as output formats. The latter is the facility
for RESTful web services. By using a RESTful architecture with Rails many of
the underlying implementation details do not need to be specified.
Ruby on Rails is separated into various
packages, namely ActiveRecord (an object-relational mapping system for database
access), ActiveResource (provides web services), ActionPack, ActiveSupport,
ActionMailer, ect. Apart from standard
packages, developers can make plugins to extend existing packages.
Ruby on
Rails web applications in Figure 2.
|
Figure 2: Ruby on Rails Web Applications Architectural Diagram |
There
are two basic principles that govern the way that Ruby on Rails works: “Don’t
Repeat Yourself” and “Convention over Configuration”. The first is often
referred to as DRY, or Don’t Repeat Yourself. The idea is to keep the language
as simplistic as possible, so the code remains simple as well. “Convention over
Configuration” means that a developer only needs to specify unconventional
aspects of the application. For example, the programmer can rely on defaults on
the naming of the classes and tables.
The
framework Ruby on Rails can be regarded as an independent platform with a full
set of required modules, documentation, ready-made solutions and high-quality
development environment. Rails can be recommended to create different
web-applications of varying complexity.
References:
1. Learning Ruby on Rails/ Rails Framework/
URL: http://www.tutorialspoint.com/ruby-on-rails/rails-framework.htm
2. Ruby a Programmer’s Best Friend/ URL: http://www.ruby-lang.org
3. Ruby on Rails/URL: http://rubyonrails.org
4. Sam Ruby, Dave Thomas,
David Heinemeier Hansson, “Agile Web Development with Rails”, Third Edition,
The Pragmatic Bookshelf., 2008.
5. The MVC Architecture/ URL: http://guides.rubyonrails.org/getting_started.html