Architecting with SOLID-Principles
In the realm of Software-Architecture, the SOLID-Principles serve as a framework for creating maintainable and scalable applications. These five principles were introduced by Robert-C-Martin to address common issues in Object-Oriented-Programming. When applied to API-Design, they facilitate the development of robust endpoints and clear Source-Code structures.
1. Single Responsibility Principle (SRP)
The SRP states that a module should have only one reason to change. In Backend-Development, this means separating concerns such as data access, business logic, and request handling. This principle is vital for effective Refactoring and Unit-Testing.
2. Open/Closed Principle (OCP)
The OCP suggests that software entities should be open for extension but closed for modification. By using Interfaces and Polymorphism, developers can add new functionality without altering existing, tested code. More details can be found on Wikipedia.
3. Liskov Substitution Principle (LSP)
The LSP ensures that a program's correctness is preserved when replacing an object of a base class with an object of a derived class. This principle prevents the misuse of Inheritance. For a deep dive, see DigitalOcean's guide.
4. Interface Segregation Principle (ISP)
ISP advises against forcing clients to depend on methods they do not use. This is achieved by splitting large Interfaces into smaller, more specific ones, which is particularly useful in Microservices architectures where lean contracts are preferred.
5. Dependency Inversion Principle (DIP)
DIP focuses on decoupling modules by ensuring that high-level modules depend on abstractions rather than low-level implementations. This is the core concept behind Dependency-Injection. Refer to Clean Coder for more examples.