Controllers, DTOs, validation, exception handling, and best practices for production REST services.
Spring Boot makes it straightforward to build REST APIs. Here’s a structured approach to design and implementation.
REST API design with Spring Boot
Core pieces
Controllers — @RestController and @RequestMapping. Use @GetMapping, @PostMapping, etc. Return DTOs or ResponseEntity for status and headers.
DTOs — Separate request/response models from entities. Use records or classes with validation (@Valid, @NotNull, @Size). Map between entities and DTOs in a service layer.
Validation — @Valid on request body; use BindingResult or @ControllerAdvice for global exception handling. Return consistent error payloads (e.g. field errors and message).
Exception handling — @ExceptionHandler in a @ControllerAdvice for MethodArgumentNotValidException, custom business exceptions, and 404/500. Use problem detail (RFC 7807) if you want a standard format.
OpenAPI/Swagger — Add springdoc-openapi or Springfox for docs and try-it-out. Annotate controllers and DTOs for better spec generation.
API design practices (team survey):
REST API practices in Spring projects
Best practices
Use HTTP verbs and status codes correctly. Version the API (path or header). Keep controllers thin; put logic in services. Secure with Spring Security and document with OpenAPI.
Building REST with Spring Boot 3:
Takeaway
Controllers + DTOs + validation + global exception handling give you a clean, maintainable API. Add Spring Data and Security as your domain and auth requirements grow.
