Introduction to Web API Architectural Styles

Introduction

In recent years, APIs' commercial usage has exponentially increased with web and mobile application development. Along with the usage of APIs, it's pretty obvious that APIs can take several different forms. When developers begin to design an API, it’s common to first decide which style/specification to use. More often than not, they opt for REST, as over 90% of developers have adopted this styleSimpson, J. 2022. “20 Impressive API Economy Statistics | Nordic APIs |.” Nordic APIs. February 9, 2022. https://nordicapis.com/20-impressive-api-economy-statistics/ ‌. However, after analyzing their technical requirements, developers can decide that their API should be handled through a different approach. In this chapter, we’ll discuss architectural styles for APIs and how they differ from each other. Moreover, we’ll examine which architectural style is suitable for which use case.

What is an architectural style?

An architectural style defines the rules and protocols to be utilized when creating our APIs. They are large-scale, standardized methods through which the system's processes are designed. These predefined structures/templates define a solution for building APIs. Architectural styles are significant because conforming to one is quicker and more efficient than defining our own solution from scratch.

Styles are similar to design patterns because they provide a template on top of which we construct our API. The decision on which architectural style to follow is of great significance because it has long-lasting effects across the entire development timeline. Different constraints, such as API consumers, business preferences, and the purpose of the API, all factor into the final decision. Once settled, it’ll be fairly difficult to change the style later in the development cycle, so we have to be certain when we decide.