302-frameworks-spring-boot-rest: Скилл разработки REST API

--- name: 302-frameworks-spring-boot-rest description: Use when you need to design, review, or improve REST APIs with Spring Boot — including HTTP methods, resource URIs, status codes, DTOs, versioning, deprecation and sunset headers, content negotiation (JSON and vendor media types), ISO-8601 instants in DTOs, pagination/sorting/filtering, Bean Validation at the boundary, idempotency, ETag concurrency, HTTP caching, error handling, security, contract-first OpenAPI (OpenAPI Generator), controller advice, and problem details for errors. Part of the skills-for-java project license: Apache-2.0 metadata: author: Juan Antonio Breña Moral version: 0.13.0 --- # Java REST API Design Principles Apply REST API design principles for Spring Boot applications. **What is covered in this Skill?** - HTTP methods (GET, POST, PUT, PATCH, DELETE) — semantic consistency - Resource URI design - HTTP status codes - Request/response DTOs with lean contracts - API versioning (URI, header, or media type — applied consistently) - Bean Validation at the boundary (@Valid/@Validated on controller inputs, 400 on failure) - Pagination, sorting, and filtering (Page/Pageable with caps) - ISO-8601 instants with offset (OffsetDateTime, Instant) in JSON contracts - Content negotiation (JSON default; vendor media types when meaningful) - Idempotency-Key support for POST creates; 409 Conflict for collisions - ETag concurrency with If-Match/If-None-Match; 412 Precondition Failed / 304 Not Modified - HTTP caching discipline (Cache-Control, ETag, Last-Modified) - Deprecation and sunset headers (Deprecation, Sunset, Link rel="successor-version") - Error handling - API security (TLS, authentication, authorization, input validation) - API contract: OpenAPI file as source of truth for API-first (OpenAPI Generator) - Controller advice and problem details (RFC 7807) **Scope:** Apply recommendations based on the reference rules and good/bad code examples. ## Constraints Before applying any REST API changes, ensure the project compiles. If compilation fails, stop immediately. After applying improvements, run full verification. - **MANDATORY**: Run `./mvnw compile` or `mvn compile` before applying any change - **SAFETY**: If compilation fails, stop immediately - **VERIFY**: Run `./mvnw clean verify` or `mvn clean verify` after applying improvements - **BEFORE APPLYING**: Read the reference for detailed rules and good/bad patterns ## When to use this skill - Review Java code for Spring Boot REST API - Apply best practices for Spring Boot REST API in Java code ## Reference For detailed guidance, examples, and constraints, see [references/302-frameworks-spring-boot-rest.md](references/302-frameworks-spring-boot-rest.md).