DESCRIPTION This book is a complete guide to designing and implementing scalable, secure, and modern APIs in a microservices architecture. Covering both synchronous communication via REST, GraphQL, and gRPC, as well as asynchronous communication with Kafka, it equips you with the tools to build efficient, reliable, and observable APIs. Learn best practices for designing REST APIs, including HTTP verb usage and the API-first approach. Explore Spring Boot technologies like WebFlux and virtual threads to build scalable REST APIs. The book also demonstrates how to use Spring Cloud Stream for broker-agnostic asynchronous communication to build robust event-driven architectures. To ensure observability, you will implement logging, monitoring, and tracing with Grafana, Prometheus, and Tempo. Security is key, and the book covers OAuth2 and OpenID Connect using Spring Security and Keycloak for centralized authentication. Finally, discover how to deploy microservices with Docker and Kubernetes, mastering containerization and orchestration. KEY FEATURES ¿ Design scalable and observable APIs for cloud-native microservices. ¿ Master REST, GraphQL, gRPC, and event-driven API best practices. ¿ Secure APIs with OAuth2, OpenID Connect, and Spring Security. WHAT YOU WILL LEARN ¿ Design scalable, secure REST APIs with Spring Boot, WebFlux, and virtual threads. ¿ Implement GraphQL and gRPC for modern APIs. ¿ Master asynchronous communication with Kafka and Spring Cloud Stream. ¿ Achieve observability with logging, metrics, and distributed tracing. ¿ Deploy microservices on Docker and Kubernetes with ease. WHO THIS BOOK IS FOR This book is for software developers and architects aiming to design scalable, secure, and modern APIs in a microservices architecture. Prior knowledge of Java and Spring Framework is recommended.