Expedite your Ruby on rails skill set with our recently designed HKR’s Ruby on rails tutorial. In this Ruby on rails tutorial, you will be learning the introduction, revolution, features, architecture, and directory structure. Ruby on rails is a type of extremely productive web application framework which is written in Ruby programming language by David Heinemeier Hansson. This tutorial will provide you a better understanding of the Ruby language. Ruby on rails tutorial is specially designed for those who would like to use the Ruby framework for developing the database packed web framework application. What you are waiting for? Let’s start learning this popular framework:
Ruby is a dynamic, reflective, object-oriented, general-purpose programming language. Ruby is a popular programming web application framework developed by Ruby developers. We can also say that Ruby on Rails is a server-side web application framework written in Ruby programming language. This Ruby language developed under the MIT university language. A rail is also a model view controller framework application that offers a default database structure, a web page, and a web service. The main motto of developing this Rail framework is to offer abstract oriented and also simplifies the common repetitive tasks. The current version of Ruby which we are using now is 18.104.22.168 (June 17th, 2020).
The following are the important factors that define why Ruby is so popular:
1. With the help of ruby on rails framework, the process of programming is much faster than when compared to another language. This is because of its object-oriented framework, vast data collection, and open-source code facility.
2. The Ruby on rails convention also makes it developers easy to develop codes, and also very flexible to move different rails projects when they consist of the same structure and coding practices.
3. Ruby on rails is a good choice for developing rapid applications as a framework and also easy to perform any changes.
4. Ruby code is a readable and self-documenting tool and increases productivity. This language increases the productivity level, as it requires less code is written and separate documentations.
5. This rail is mainly developed to support the testing team; this is because it offers good testing framework applications.
6. Most of the rails libraries are open source, when compare to other commercial development frameworks and doesn’t require any licensing cost.
Below are the major features offered by the Ruby on rails framework:
Rails 6.0 now ships with inbuilt support for mail guns, mand drills, postmark and send grills. The email use processed via active record and stored on the cloud through active storage and can be sent to multiple mailboxes.
Most WYSIWYG, editors are wrappers around HTML, APIs, and reverse engineer from there. Action text (Trix) includes active storage backed file, image processing, and a text-processing flow that ties it all together.
Rails 6 has launched support for multiple primary databases, which is very useful for applications seeking to scale horizontally rather just vertically or using NoSQL and SQL databases in tandem.
To enable efficient usage of multiple codes (either on your machine or a CI server). Rails 6 introduced the option to spin multiple processes and threads to execute your test suites in parallel leading to faster deployments.
Zeitwerk is the new code loader for rails, built from scratch. It enables hot reloads of code not just within rails but also from the gems as well.
The following diagram explains the work nature and component details of Ruby on rails architecture design:
Ruby on rails uses the Model View Controller or MVC architectural pattern. This model also follows the convention over multiple configuration rules this is also known as coding by convention. The main purpose of Ruby on rails architecture is to increase the performance of the application.
Let me explain the components of Ruby on rails architecture:
Model: this is the lower level pattern used for maintaining the data structure.
View: this type of component is used to display the data or any portion of the data mainly used by users.
Controller: this component consists of software codes. These codes are often used to control the interactions between the model and view components.
As we already know that Ruby on rails is a popular tool and this isolates the application logic from the available user interface layer and also supports the separation of software concerns. The main function of the controller is to receive all the requests for the application developments and then it works with a model that prepares any data which are needed by the view component. The view then makes use of these data structures prepared by the controller component to create final presentable responses. The view is a script-based templates system available in the following programming languages like JSP, ASP, PHP, and also it is very easy to integrate with AJAX technologies.
A framework is nothing but a simple program, a set of different programs, and a code library. The code library in the Ruby framework helps you to write any programming applications. The following three major tasks need to be performed during the time of framework development application.
The domain is known as a popular universal application, and the domain can be of any type such as music stores, universities, address books, dating services, and a hardware inventory. The main task is to figure out what content in it, what type of entities exist in the universe, and how these items are related to each other. This task is equivalent to modeling a database structure to maintain the entities and their relationship.
The domain model is static, and here you have to make it dynamic. Here addresses are added to an address book and musical scores will be purchased from music stores. Users can log into any dating service. Students can register for university classes. All you need to do is identify all the possible scenarios or any actions that the element can participate in a domain.
This is the final task, here you can think about web browser terms. Once you have decided that, your domain name is a student and they register for classes in universities. These domain details can be stored in form of a welcome page, confirmation page, and registration page. Each of these pages, views, shows how things stand at a certain point.
This model view controller framework divides the work of any application into three different cooperative subsystems.
This model feature maintains the relationship between the object and any database applications. It also helps to handle validations, associations, transactions, and more. The model subsystem is implemented in the ActiveRecord class library, this offers an interface and binding between any two tables in a relational database management system, and the ruby program codes also are executed.
This is a type of presentation of data method in a particular format, which is triggered by a controller decision mainly used to present the data. These data are available in the form of script-based templates such as JSP, ASP, Ajax, and PHP.
This type of method directs the data traffic, querying the data models for specific data tasks, and also organizes the data sets (like searching, messaging, and sorting) into a form that should fit into the given view.
Below is the standard directory syntax:
tp > cd/usr/local/lib/ruby/gems/2.2.0/gems
tp > ls
The three MVC frameworks on Ruby rails can be represented as:
Over a windows installation, you can see them like this:
tp > cd ruby\lib\ruby\2.2.0\gems
When you use the rails helper script helps to create an application, and this creates the entire data structure for the given application.
Now it’s time to know the purpose of each directory:
1. app: this directory helps to organize the application component. This consists of various subdirectories that hold the components like view or (views and helpers), the controller (controller method), and the backend level business logic (a type of model).
2. app/controllers: the controller subdirectory where ruby on rails used to find the controller classes. A controller in rails handles web-based application requests from the user.
3. app/helpers: The helpers’ subdirectory consists of helper classes that are used to assist the MVC or model, view, and controller classes. This helper subdirectory keep the model, controller, and view code can be focused.
4. app/models: this model subdirectory consists of classes that help the models to wrap the data stores in the application database. In most frameworks, the part of the application can grow messy, verbose, tedious, and error-prone. Ruby on rails makes it simple.
5. app/view: this view subdirectory contains the display templates to fill in the data from any application, convert them to HTML, and return these data to the user’s browser.
6. app/view/layout: this subdirectory holds the template files for layouts that will be used with views. This model helps the common header/footer method to wrap up the views.
7. Components: this component directory contains tiny self-contained applications, views, controller, and bundle models.
8. Config: this config subdirectory consists of a small number of configuration codes. There are n –number configurations available such as database configuration (in database.yml), daily environment structure (environment. rb), and routing of incoming web requests.
9. db: we already know that the rails application will have the model object that helps to access relational database tables. With the help of db you can also script the database models and create a place in the directory to store these data.
10. lib: here you will put class libraries here, namely vendor libraries.
11. log: in this subdirectory, you can store the error log files. Ruby on rails creates the script to manage various error logs related to relational database models. Here you will find the server logs such as development.log files, test.log files, and production.log files.
13. Script: this subdirectory file holds the scripts which are used to launch and manage various rails tools. For example there are scripts that are used to generate the codes (generate) and launch the webserver (server applications).
14. Test: This test subdirectory helps you to write and create the rails files for you, and here you will find the subdirectory mocks (mock files), unit tests (unit), fixtures (fixture file), and functional tests (functional).
Tmp: ruby on rails uses the directory which holds the temporary data files only used for intermediate processing.
Vendor: This vendor subdirectory library usually provided by third-party vendors (like security libraries, and database utilities).
Apart from these files, there are two more directories available in demo files:
README: this file contains basic details like rail applications and a description of the directory structured files.
Rakefile: this subdirectory is similar to UNIX Make files, and this helps in building, packaging, and testing the ruby rails codes. This type of demo file used by rake utility approaches and also supports Ruby installation.
In this section, we are going to explain how to create your first ever ruby applications:
Workflow for creating rails applications:
Important points to remember:
Creating an empty rails web application:
Steps included are:
1. First go to the ruby installation directory and create your application.
2. Now run the following command to generate a skeleton for the library application. This will create the file directory structure in the domain directory.
The syntax looks like this way:
tp > rails new library
This will generate the subdirectory for the library database application that holds the complete directory tree structure folder and file directory for an empty ruby on rails application.
Ruby on rails application will run under virtual web server application server, this is considered to be the most convenient way to generate a ruby web application. The ruby web application is used to build the WEBrick web server. The server will be started from the application directory as follows:
Here the port number is 3000:
tp > cd ruby \library
tp \ruby\library\> Rails server
This syntax generates the auto code:
$ rails server
DL is presented, now please use the fiddle
= > booting WEBrick application
= > rails 4.2.3 application starts in the development on HTTP : //localhost:3000
= > run “rails server –h” for more project startup options
= > ctrl – C to shut down the server application
This will start the WEBrick web server application.
The output is as follows:
Ruby on rails migration allows you to make use of ruby to perform any type of modification in data schema and also helps to control the setup application.
The following are the very important concepts of migration;
1. Terms of the developer: in this section, if one person makes any schema changes, then the other developer will updater and run the application with the help of “rake migrates”.
2. Production server: after the “rake migrates” step, this will roll out the new release to bring the database application.
3. Multiple machines: once you develop this application on both desktop and laptop, and migrations on rails will help you to keep all the applications to perform synchronization.
1. create_table (name, options)
2. Drop_table (name)
3. rename _ table (old_name, new_name)
4. Add_column (table_name, column_name, and types)
5. Rename_column (table_name, column_name, and new_column_name)
6. Change_column (table_name, column_name, and type)
7. Remove_column (table_name, and column_name)
8. add_index (table_name, column_name, and index_type)
9. Remove_index (table_name, and column_name)
This type of migration supports different data types. They are;
1. String: this data type is used for small data types namely title.
2. text: this data type is used to store textual data like the description.
3. Integer: used to store whole numbers.
4. Float: used to store decimals.
5. Datestamp and timestamp: used to store the date and time values into a column.
6. date and time: used to store either date value or time value.
7. binary: used to store the data such as images, movies, and audio.
8. Boolean: used to store true or false values.
Valid column options are:
1. limit (: limit = > “50”)
2. default (: default = > “blah”)
3. null (: null = > false implies NOT NULL)
Scaffolding in ruby on rails used to provide more than one cheap demo thrills. Few details regarding scaffolding:
1. With the help of scaffolding you can quickly get the codes in front of your feedback.
2. Here you will be motivated by quicker success.
3. Scaffolding helps to learn how ruby on rails works by generating the codes.
4. In any situation, you can make use of scaffolding as a foundation to start web development.
The syntax is as follows:
Tp > rails new cookbook
Setup the database:
Here is the code:
MySQL > create database COOKBOOK,
Query OK, 1 row affected (0.01 secs)
MySQL > grant all privileges on cookbook. *
To “root” @” localhost” identified by “password”;
Query OK, 0 rows affected (0.00 sec)
MySQL > FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)
Now it’s time to perform scaffolding stages:
Then you will get the scaffold code as follows:
AJAX technology incorporates the following:
AJAX technology enables you to retrieve the data for several web pages without the need for any content refreshment. In the basic AJAX architecture, the user can click or submits a form. The form will be submitted to the server, and this sends back any response. Then the response will be displayed on the new page.
Ruby on rails is a simple, consistent model for implementing AJAX operations. Once the web browser renders the data and displays the initial web pages.
The following are the AJAX operations:
1. Trigger fires:
This trigger could be the user by clicking on a button or link, and then the user makes changes to the data in a field.
2. The web client calls the server:
3. The server does processing:
The server-side action handler or rails controller action does something with available data and returns the HTML fragments.
4. The client receives the response:
This ruby on rails active record is the object or relational mapping (ORM) layer supplied with rails. This closely follows the standard ORM model:
Translate the domain model into SQL is generally a straight forward method. Here you can write user-friendly rails-SQL.
You to follow the following rules:
To create the active record files you have to use these commands:
Library \> rails script/ generate model book]
Library \> rails script/ generate model subject
You can get the content by using the following command:
Class book < activerecord:: base
The content is available in the subject.rb –
Class subject < ActiveRecord :: Base
When you are working with more than one model in your ruby on rails application, then you need to create the relationship between these models.
A one-to-one relationship can exist if one item already exists in another item.
A one-to-many relationship exists when a single object can exist or member of many other objects.
A many-to-many relationship exists when the first object is related to one or more of the second object, and vice versa.
In this ruby on rails tutorial, you will be learning the definition, architecture, invention, MVC frameworks, Components, Scaffolding, and the advantages. Learning this tutorial will help you to gain knowledge in the Ruby on rails framework. To enhance your industry-oriented knowledge in this tool, you have to take any online course related to technology and this will also help you to get hands-on experience.We offer the best training in the current market and also our course contents are designed by the SME team. Our technical team also provides 24/7 online support for any course-related queries.
Batch starts on 1st Aug 2021, Weekend batch
Batch starts on 5th Aug 2021, Weekday batch
Batch starts on 9th Aug 2021, Weekday batch
5th April | 08:00 AM