ContentCachingResponseWrapper produce respuesta vacía

Estoy intentando implementar filtro para registrar solicitudes y respuestas en Spring MVC aplicación Spring MVC . Yo uso el siguiente código:

 @Component public class LoggingFilter extends OncePerRequestFilter { private static final Logger LOGGER = LoggerFactory.getLogger(LoggingFilter.class); @Override protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException { ContentCachingRequestWrapper requestWrapper = new ContentCachingRequestWrapper(request); ContentCachingResponseWrapper responseWrapper = new ContentCachingResponseWrapper(response); LOGGER.debug(REQUEST_MESSAGE_FORMAT, requestWrapper.getRequestURI(), requestWrapper.getMethod(), requestWrapper.getContentType(), new ServletServerHttpRequest(requestWrapper).getHeaders(), IOUtils.toString(requestWrapper.getInputStream(), UTF_8)); filterChain.doFilter(requestWrapper, responseWrapper); LOGGER.debug(RESPONSE_MESSAGE_FORMAT, responseWrapper.getStatus(), responseWrapper.getContentType(), new ServletServerHttpResponse(responseWrapper).getHeaders(), IOUtils.toString(responseWrapper.getContentInputStream(), UTF_8)); } } 

Entonces, recibo mi solicitud y respondo registrado como se esperaba. Aquí están los registros:

 2016-10-08 19:10:11.212 DEBUG 11072 --- [qtp108982313-19] by.kolodyuk.logging.LoggingFilter ---------------------------- ID: 1 URI: /resources/1 Http-Method: GET Content-Type: null Headers: {User-Agent=[curl/7.41.0], Accept=[*/*], Host=[localhost:9015]} Body: -------------------------------------- 2016-10-08 19:10:11.277 DEBUG 11072 --- [qtp108982313-19] by.kolodyuk.logging.LoggingFilter ---------------------------- ID: 1 Response-Code: 200 Content-Type: application/json;charset=UTF-8 Headers: {} Body: {"id":"1"} -------------------------------------- 

Sin embargo, se devuelve la respuesta vacía. Aquí está la salida de curl :

 $ curl http://localhost:9015/resources/1 --verbose * Trying ::1... * Connected to localhost (::1) port 9015 (#0) > GET /resources/1 HTTP/1.1 > User-Agent: curl/7.41.0 > Host: localhost:9015 > Accept: */* > < HTTP/1.1 200 OK < Date: Sat, 08 Oct 2016 17:10:11 GMT < Content-Type: application/json;charset=UTF-8 < Content-Length: 0 < * Connection #0 to host localhost left intact 

¿Algunas ideas?

Gracias

Después de un par de horas de lucha, finalmente encontré la solución.

En resumen, se debe llamar a ContentCachingResponseWrapper.copyBodyToResponse() al final del método de filtro.

ContentCachingResponseWrapper almacena en caché el cuerpo de respuesta leyéndolo de la secuencia de salida de respuesta. Entonces, la transmisión se vacía. Para escribir una respuesta a la secuencia de salida ContentCachingResponseWrapper.copyBodyToResponse() debe utilizar.

Finalmente resolvió el problema. Aquí está la solución perfecta:

 import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.databind.ObjectMapper; import org.apache.commons.io.IOUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.http.*; import org.springframework.stereotype.Component; import org.springframework.web.filter.OncePerRequestFilter; import org.springframework.web.util.ContentCachingRequestWrapper; import org.springframework.web.util.ContentCachingResponseWrapper; import javax.servlet.FilterChain; import javax.servlet.ServletException; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.net.URI; import java.util.Enumeration; import java.util.Map; import static java.nio.charset.StandardCharsets.UTF_8; import static net.logstash.logback.marker.Markers.appendFields; @Component public class LoggingFilter extends OncePerRequestFilter { private static final Logger LOGGER = LoggerFactory.getLogger(LoggingFilter.class); @Autowired private ObjectMapper objectMapper; @Override protected void doFilterInternal(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, FilterChain filterChain) throws ServletException, IOException { ContentCachingRequestWrapper requestWrapper = new ContentCachingRequestWrapper(httpServletRequest); ContentCachingResponseWrapper responseWrapper = new ContentCachingResponseWrapper(httpServletResponse); filterChain.doFilter(requestWrapper, responseWrapper); String requestUrl = requestWrapper.getRequestURL().toString(); HttpHeaders requestHeaders = new HttpHeaders(); Enumeration headerNames = requestWrapper.getHeaderNames(); while (headerNames.hasMoreElements()) { String headerName = (String) headerNames.nextElement(); requestHeaders.add(headerName, requestWrapper.getHeader(headerName)); } HttpMethod httpMethod = HttpMethod.valueOf(requestWrapper.getMethod()); Map requestParams = requestWrapper.getParameterMap(); String requestBody = IOUtils.toString(requestWrapper.getInputStream(),UTF_8); JsonNode requestJson = objectMapper.readTree(requestBody); RequestEntity requestEntity = new RequestEntity<>(requestJson,requestHeaders, httpMethod, URI.create(requestUrl)); LOGGER.info(appendFields(requestEntity),"Logging Http Request"); HttpStatus responseStatus = HttpStatus.valueOf(responseWrapper.getStatusCode()); HttpHeaders responseHeaders = new HttpHeaders(); for (String headerName : responseWrapper.getHeaderNames()) { responseHeaders.add(headerName, responseWrapper.getHeader(headerName)); } String responseBody = IOUtils.toString(responseWrapper.getContentInputStream(), UTF_8); JsonNode responseJson = objectMapper.readTree(responseBody); ResponseEntity responseEntity = new ResponseEntity<>(responseJson,responseHeaders,responseStatus); LOGGER.info(appendFields(responseEntity),"Logging Http Response"); responseWrapper.copyBodyToResponse(); } }