Mastering API Architecture

Introduction

In this introduction, you will discover the basics of APIs and their potential to be part of the architecture journey. We will introduce a lightweight definition for APIs and their use in and out of process. In order to demonstrate the importance of APIs, we will introduce the conference system case study, a running example that will evolve throughout the book. Out-of-process APIs allow you to think beyond a simple three-tiered architecture; we will introduce traffic patterns and their importance to demonstrate this. We will outline a summary of the case study steps, allowing you to skip ahead if an area is of interest to you straight away.

In order to present APIs and their associated ecosystem, we will use a series of important artifacts. We will introduce the case study with C4 model diagrams and revisit the specifics and logic behind the approach. You will also learn about the use of Architecture Decision Records (ADRs) and the value of clearly defining decisions across the software lifecycle. As the introduction closes, we will outline ADR Guidelines—our approach to help you make decisions when the answer is “it depends.”

The Architecture Journey

Anyone who has taken a long journey will no doubt have encountered the question (and possibly persistently) “are we there yet?” For the first few inquiries, you look at the GPS or a route planner and provide an estimate—hoping that you don’t encounter any delays along the way. Similarly, the journey to building API-based ...