java 42 lines · 8 steps

Adding deprecation headers in Spring

A ResponseBodyAdvice that stamps Deprecation and Sunset headers onto responses from endpoints marked as deprecated.

Explained by highlit

Spring Intermediate response interception http headers api deprecation annotations cross-cutting concerns

1@ControllerAdvice
2public class DeprecationHeaderAdvice implements ResponseBodyAdvice<Object> {
3 
  private final Clock clock;
5 
  public DeprecationHeaderAdvice(Clock clock) {
      this.clock = clock;
  }
9 
  @Override
  public boolean supports(MethodParameter returnType, Class<? extends HttpMessageConverter<?>> converterType) {
      return returnType.hasMethodAnnotation(Deprecated.class)
              || returnType.hasMethodAnnotation(Sunset.class);
  }
15 
  @Override
  public Object beforeBodyWrite(Object body,
                                MethodParameter returnType,
                                MediaType selectedContentType,
                                Class<? extends HttpMessageConverter<?>> selectedConverterType,
                                ServerHttpRequest request,
                                ServerHttpResponse response) {
      HttpHeaders headers = response.getHeaders();
      headers.add("Deprecation", "true");
25 
      Sunset sunset = returnType.getMethodAnnotation(Sunset.class);
      if (sunset != null) {
          OffsetDateTime date = OffsetDateTime.parse(sunset.value());
          headers.add("Sunset", date.format(DateTimeFormatter.RFC_1123_DATE_TIME));
          if (!sunset.link().isBlank()) {
              headers.add("Link", "<" + sunset.link() + ">; rel=\"deprecation\"");
          }
      }
34 
      LoggerFactory.getLogger(getClass()).warn(
              "Deprecated endpoint {} invoked from {}",
              returnType.getMethod(),
              request.getRemoteAddress());
39 
      return body;
  }
42}

01 / 01

STEP 01

Walkthrough

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Three takeaways

1ResponseBodyAdvice lets you rewrite response bodies and headers globally without touching individual controllers.
2supports() acts as a filter so the expensive per-response logic only runs where it actually applies.
3Driving behavior off method annotations keeps deprecation policy declarative and colocated with the endpoint it describes.

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