Writing Loosely Coupled Code in Ruby on Rails

Best Practices and Techniques

Patrick Karsh


Loosely Coupled but not on Hinge

Ruby on Rails is a model-view-controller (MVC) framework, providing default structures for a database, a web service, and web pages. One of the critical aspects of building maintainable and scalable applications in Rails — or any framework, for that matter — is writing loosely coupled code. Loosely coupled code refers to components or classes that are independent of each other, making the system more flexible, scalable, and easier to manage. This article explores best practices and techniques for writing loosely coupled code in Rails, ensuring your application remains robust and adaptable.

Understanding Coupling in Rails Applications

Coupling measures how closely connected two routines or modules are; the less they know about each other, the more loosely coupled they are. High coupling can lead to a fragile codebase that’s hard to test, maintain, and extend. Conversely, low coupling enhances modularity, making your codebase more resilient to changes and easier to understand.

Strategies for Achieving Low Coupling in Rails

Follow the Single Responsibility Principle (SRP)

Each class in Rails should have a single responsibility and thus only a single reason to change. This principle helps in minimizing dependencies within the system. For example, instead of creating a monolithic User model that handles authentication, profile management, and notifications, break it down into smaller, focused classes or modules.

Instead of having a User model that handles everything, you could separate concerns into more focused classes. For example, if your User model is handling user authentication, you could create a service object for authentication:

This way, the User model doesn't need to know how authentication is performed, reducing its responsibilities.

Use Service Objects



Patrick Karsh

NYC-based Ruby on Rails and Javascript Engineer leveraging AI to explore Engineering. https://linktr.ee/patrickkarsh