Single Responsibility Principle (SRP)
This principle states that each class should have a single responsibility. It emphasizes that a class should perform one specific function and not have too many reasons to change.
Example: Managing user information and sending email notifications.
class UserManager
def create_user(user_data)
# Logic for creating a user
end
end
class EmailService
def send_email(email_data)
# Logic for sending an email
end
end
Open/Closed Principle (OCP)
This principle encourages extending functionality by adding new code rather than modifying existing code.
Example: Handling different payment methods in an e-commerce application.
class PaymentProcessor
def process_payment
# Common logic for payment processing
end
end
class CreditCardPaymentProcessor < PaymentProcessor
def process_payment
# Logic for processing credit card payment
end
end
class PayPalPaymentProcessor < PaymentProcessor
def process_payment
# Logic for processing PayPal payment
end
end
Liskov Substitution Principle (LSP)
This principle asserts that objects of a derived class should be substitutable for objects of the base class without affecting the correctness of the program.
Example: Managing geometric shapes.
class Shape
def area
# Common logic for calculating area
end
end
class Rectangle < Shape
def area
# Logic for calculating area of rectangle
end
end
class Square < Shape
def area
# Logic for calculating area of square
end
end
Interface Segregation Principle (ISP)
This principle advises breaking interfaces into smaller ones to avoid forcing classes to implement methods they don't need.
Example: Interfaces for updating and displaying data.
module UpdateableFeature
def update_feature
# Logic for updating feature
end
end
module DisplayableFeature
def display_feature
# Logic for displaying feature
end
end
Dependency Inversion Principle (DIP)
This principle suggests using dependency injection to manage dependencies.
Example: Using dependency injection to manage dependencies.
class OrderProcessor
def initialize(db_connection, email_service)
@db_connection = db_connection
@email_service = email_service
end
end
Remember that applying SOLID principles in Ruby should be done flexibly based on the specific purpose of your project and your understanding of SOLID and Ruby.