Architectural Pattern vs Architectural Style

To understand these two terms we can make an analogy by taking the kind of builds in a city, we can find gothic churches and minimalist houses, and each one of those buildings contains specific patterns that need to be followed step by step in order to have the correct style. The same happens when we are building a software system, we follow specific design patterns that are part of an architectural style.

Today let us talk about two similar terms “Architectural Pattern” and “Architectural Style”. A simple view looks pretty identical, and sometimes we could get confused about how to define and implement them in software development.

It’s important to note that a software architecture style is a broader framework, while software architecture patterns are specific solutions within that framework.

Let me give you a brief introduction about those terms, and don’t worry; we will go deep in the following article sections.

What is architectural Style?

Architectural Style makes reference to the way of the organization and distribution of the components of our system. For example, an architectural style could be an architecture based on layers, where the functionalities are distributed on its own layers, or a client-server architecture, where the client makes requests to a server.

Now that we have a definition of architectural styles we can list some examples:

Layer architecture: 

Organizes the application into separate layers with specific responsibilities, such as the presentation layer, the application layer, and the data layer.

Example:

Think about an application with separate layers for the user interface, application logic, and data access. For example, in an e-commerce web application, where the presentation layer consists of the user interface, the application layer handles the business logic and transactions, and the data layer stores and retrieves data from a database.

Microservices-based architecture: 

Divides the application into small, independent services that communicate with each other through an API.

Example:

A large-scale online marketplace, where each microservice handles a specific aspect of the application such as product search, payment processing, or customer management.

Event-based architecture:

Uses events and messaging for communication between application components.

Example:

A financial trading platform, where events such as price changes or market events trigger updates and calculations in other parts of the system.

What are Architectural Patterns?

An architectural pattern in software development is a recurring and well-proven solution to a common problem in software architecture. Architectural patterns provide a framework for resolving specific problems such as scalability, security, and system integration, among others.

Now that we have a definition of architectural patterns we can list a couple of examples:

MVC (Model-View-Controller) pattern:

Separates business logic, presentation, and control into separate components.

Example:

A web application that allows users to manage their finances by categorizing their expenses. The Model component contains the financial data, the View component displays the data to the user, and the Controller component manages user interactions and updates the Model as needed.

Publish-Subscribe pattern:

Uses an intermediary to publish and subscribe to messages in the application.

Example:

An online forum application where users can subscribe to specific topics and receive notifications when new posts are made. The application acts as the intermediary that publishes the messages, and the users subscribe to the messages they are interested in.

Repository pattern: 

Provides an intermediate layer for data access, which separates business logic from data access logic.

Example:

A database-driven e-commerce website that provides a product catalog for customers to browse and purchase products. The Repository component serves as an intermediary layer between the business logic and the database, allowing the business logic to retrieve and manipulate the data without having to directly interact with the database.

Conclusion:

We can conclude that the use of architectural patterns in software development is important for several reasons:

• Improves software quality by providing robust solutions to common problems in software architecture, thereby increasing software quality and reliability.
• Facilitates scalability and maintainability by helping to design systems that are scalable and easy to maintain, reducing development time and cost.
• It facilitates system integration by helping to integrate different components and systems, which improves efficiency and interoperability.
• Improves security by helping to identify and address security issues in software design, which improves system security.