How to log RestTemplate request and response with spring?

Question

I'm using Spring with RestTemplate to execute HTTP GET requests.

How can I log any request and response data to a log file automatically on each request?

Answer 1

You can achieve this by using ClientHttpRequestInterceptor in Spring. You have to override method intercept of interface ClientHttpRequestInterceptor.

Below is the code snippet :

@Component
public class LogRequestResponseFilter implements ClientHttpRequestInterceptor {

private static final Logger logger=LoggerFactory.getLogger(LogRequestResponseFilter.class);

   @Override
   public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution)
         throws IOException {

      traceRequest(request, body);
      ClientHttpResponse clientHttpResponse = execution.execute(request, body);
      traceResponse(clientHttpResponse);

      return clientHttpResponse;
   } 

 private void traceRequest(HttpRequest request, byte[] body) throws IOException {
      logger.debug("request URI : " + request.getURI());
      logger.debug("request method : " + request.getMethod());
      logger.debug("request body : " + getRequestBody(body));
   }

   private String getRequestBody(byte[] body) throws UnsupportedEncodingException {
      if (body != null && body.length > 0) {
         return (new String(body, "UTF-8"));
      } else {
         return null;
      }
   }


  private void traceResponse(ClientHttpResponse response) throws IOException {
      String body = getBodyString(response);
      logger.debug("response status code: " + response.getStatusCode());
      logger.debug("response status text: " + response.getStatusText());
      logger.debug("response body : " + body);
   }

   private String getBodyString(ClientHttpResponse response) {
      try {
         if (response != null && response.getBody() != null) {// &&
                                                              // isReadableResponse(response))
                                                              // {
            StringBuilder inputStringBuilder = new StringBuilder();
            BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(response.getBody(), StandardCharsets.UTF_8));
            String line = bufferedReader.readLine();
            while (line != null) {
               inputStringBuilder.append(line);
               inputStringBuilder.append('\n');
               line = bufferedReader.readLine();
            }
            return inputStringBuilder.toString();
         } else {
            return null;
         }
      } catch (IOException e) {
         logger.error(e.getMessage(), e);
         return null;
      }
   }