Spring Boot REST API Best Practices - Part 1

A practical guide to building a Spring Boot REST API following best practices. Covers setting up a Spring Boot project with PostgreSQL, Flyway migrations, and Testcontainers. Demonstrates common mistakes when implementing a GET collection endpoint—such as exposing JPA entities directly and loading all records without pagination—and shows how to fix them using DTO projections, a generic PagedResult wrapper, and paginated queries via Spring Data JPA. Includes integration tests using RestAssured and Testcontainers.