package com.meltmedia.jgroups.aws;
   
   import com.amazonaws.AmazonServiceException;
   import com.amazonaws.Request;
   import com.amazonaws.handlers.RequestHandler;
   import com.amazonaws.transform.Unmarshaller;
   import com.amazonaws.util.TimingInfo;
   import org.jgroups.logging.Log;
   import org.jgroups.logging.LogFactory;
  import org.w3c.dom.Node;
  
  import javax.xml.transform.Result;
  import javax.xml.transform.Source;
  import javax.xml.transform.Transformer;
  import javax.xml.transform.TransformerFactory;
  import java.io.StringWriter;
  
  /**
   * This class will log the request along with the response from the AWS ec2 service on fault only.
   *
   * @author John McEntire
   */
  @SuppressWarnings("deprecation")
  class AWSFaultLogger implements Unmarshaller<AmazonServiceException, Node>, RequestHandler {
    private static Log log = LogFactory.getLog(AWS_PING.class);
    private final ThreadLocal<Request<?>> request = new ThreadLocal<>();
  
    @Override
    public AmazonServiceException unmarshall(Node node) throws Exception {
      try {
        final TransformerFactory tfactory = TransformerFactory.newInstance();
        final Transformer xform = tfactory.newTransformer();
        final Source src = new javax.xml.transform.dom.DOMSource(node);
        final StringWriter writer = new StringWriter();
        final Result result = new javax.xml.transform.stream.StreamResult(writer);
  
        xform.transform(src, result);
        log.error("AWS Exception: [%s] For request [%s]", writer, request.get());
      } catch (Throwable t) {
        log.debug("Failed to log xml soap fault message.", t);
      } finally {
        request.remove();
      }
      return null;
    }
  
    @Override
    public void afterError(Request<?> request, Exception e) {
      this.request.remove();
    }
  
    @Override
    public void afterResponse(Request<?> request, Object obj, TimingInfo timing) {
      this.request.remove();
    }
  
    @Override
    public void beforeRequest(Request<?> request) {
      this.request.set(request);
    }
  }