Let’s start off with the
basics! Ruby is an ideal example of a purist’s concept of a pure object-oriented
language with an easy-to-write and maintain syntax that should be any
programmer’s dream come-true. And Rails? A framework that is open source and is
perfectly suited to the development of web-based, database-driven applications;
that’s Rails for you. The advantage of this framework is its capability to
develop applications up to 10x faster than technologies, such as Java! Ruby and
Rails leverage each other and the two most important principles of lesser lines
of code and convention over configuration are derived from this amalgamation.
As you start developing RoR web applications, you’ll realize that the mount of
code required is way lesser than other technologies. On the other hand, we have
convention over configuration which cuts the umbilical cord for all XML files.
You can literally do away with all XML configuration files, as simple
programming conventions take their place.
Okay, now onto the main
course! We will try and explain the process of developing
a web-based, database-driven application using Ruby on Rails.
The
Installation
Though Rails has always
been a breeze when it came to installation and configuration, there are many
tools available today that make this job even simpler. Based on your operating
environment, you can choose any one of the following options: Instant Rails for
Windows, Locomotive for Mac OS X, and Rails LiveCD for Linux.
The Purpose
The application we are
aiming to design is supposed to show a list of all books, create and edit
existing book titles, and categorize books to categories according to their
genre, such as crime fiction or sci-fi. Designing the structure and defining
the ground rules for standardizing such as app is important as the UI
experience of a user should not differ from page to page.
The Process
Here we have our first
brush with the iterative and incremental approach offered by Rails. Below are
the steps required to develop any application in Rails:
Create a Rails Web
Application shell (empty app)
Choose Rails’ default
database name or specify one yourself
Create the database if
it doesn’t exist
Pick and choose your
application’s features
Create the tables that
your app will use, if they don’t already exist
Create a code base for
the tables
Optimize and modify the
code as per your need
Repeat steps 4 -7 till
your application development is complete
Step 1 - Create a Rails Web Application shell (empty
app)
Rails provides an
endearing feature where every Rails app has the same core structure. So,
whenever you want to create a new app, Rails automatically generates a
structure for this application. This is something that many Ruby on Rails
consultants cherish as it affords them the extra bandwidth that they can invest
in thinking of innovative features for the app. Your app will always reside
under the Rails Root directory which may be termed differently based on the
environment you use. Open a command prompt window and find your way to this
directory. All you have to do now is christen your app. Type rails library
(remember, our app is for a dynamic database of books?) and voila! Rails
creates your app subdirectory and a tree of folders and files – your empty
Rails app. Rails automatically writes code to most of these files in the
various subdirectories. But there are a few that need a special mention:
app/controllers –
contains all the controller classes. A controller is a component that handles
incoming web requests from users.
app/views – contains
display templates that are converted to HTML after filling in data and returned
to the user’s browser.
app/models – contains
classes that model and wrap the application database contents.
app/helpers – contains
helper classes to do what their name suggests: help the model, view and
controller classes in their function.
Step 2 - Choose Rails’ default database name or
specify one yourself
The database we need to
use for this application needs to be specified in a fixed format; its name
concatenated with development, which in this instance means our database will
be called library_development. We should also try and leave the development
database password blank as it is a convention followed by Rails. If you ever
need to modify the database name or password, all you have to do is access and
edit \library\config\database.yml.
Step 3 - Create the database if it doesn’t exist
Now, we create our
database. Ensure that the MySQL engine is running and log into the command
prompt as a root user. Enter and execute the following commands:
mysql –u root –p
create database library_development
grant all on library_development.* to
‘ODBC’@’localhost’;
exit
Step 4 - Pick and choose your application’s features
Here’s what makes Rails
different from other application development technologies. Any data we assign
to rails, it assumes that we will need to create, read, update and delete it.
In our case, we too need to create book titles, edit them, delete them, etc.
Therefore after specifying the tables we want for the app, Rails will
automatically generate all the basic code. Now, do you understand why Rails is
up to 10x faster?
Step 5 - Create the tables that your app will use, if
they don’t already exist
We are not going to
dwell on creating on tables and defining foreign keys here. All we need to know
is that 2 tables are required, one for the book titles and another for the categories
with a one-to-many relationship.
After creating tables in
MySQL, on the command prompt ensure that you are in the library_development
directory and execute the following command:
mysql cookbook2_development <db\create.sql
If you return back to
the command prompt, without any messages or error, everything went fine.
Step 6 - Create a code base for the tables
Here, we use scaffolding
– a concept unique to Rails that allows us to generate a basic application
structure without breaking a sweat. Execute the following command on in your
app subdirectory:
ruby script\generate
scaffold book book
This generates the model, view and controller files for the section of
our app that will use the Titles tables. We do the same for the category part:
ruby script\generate scaffold category category
Step 7 - Optimize and modify the code as per your need
We will use Mongrel; a
popular Rails-friendly web server for hosting our app locally. In the library
subdirectory execute the following command to rev up Mongrel:
mongrel_rails
start
And, we are done! A few more lines of code would be required to patch
things up and display proper messages but mostly, our app is up and running in
the blink of an eye!
We are a Ruby on Rails development company that has been leveraging its
extraordinary advantages for quite some time, to design and develop
cutting-edge application for our clients. We provide offshore software development services to companies and organization across the globe and have
achieved a 100% development rate doing the same. If you wish to harness the
tantalizing power of Ruby on Rails for the development of your application, do
not hesitate to get in touch with us and hire RoR developers from our talent
pool. You web application will be up and running in no time, and will function
par excellence; that’s a promise!
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