HDDS-2206. Separate handling for OMException and IOException in the Ozone Manager. Contributed by Supratim Deka (#12)

Author: supratimdeka

hadoop-ozone/ozone-manager/src/main/java/org/apache/hadoop/ozone/protocolPB/OzoneManagerProtocolServerSideTranslatorPB.java

@@ -22,6 +22,7 @@
 import org.apache.hadoop.ozone.OmUtils;
 import org.apache.hadoop.ozone.om.OzoneManager;
 import org.apache.hadoop.ozone.om.exceptions.NotLeaderException;
+import org.apache.hadoop.ozone.om.exceptions.OMException;
 import org.apache.hadoop.ozone.om.protocolPB.OzoneManagerProtocolPB;
 import org.apache.hadoop.ozone.om.ratis.OzoneManagerDoubleBuffer;
 import org.apache.hadoop.ozone.om.ratis.OzoneManagerRatisServer;
@@ -34,6 +35,7 @@
 
 import com.google.protobuf.RpcController;
 import com.google.protobuf.ServiceException;
+import org.apache.hadoop.util.StringUtils;
 import org.apache.ratis.protocol.RaftPeerId;
 import org.apache.ratis.util.ExitUtils;
 import org.slf4j.Logger;
@@ -151,12 +153,21 @@ private OMResponse createErrorResponse(
             OzoneManagerRatisUtils.exceptionToResponseStatus(exception))
         .setCmdType(cmdType)
         .setSuccess(false);
-    if (exception.getMessage() != null) {
-      omResponse.setMessage(exception.getMessage());
+    String errorMsg = exceptionErrorMessage(exception);
+    if (errorMsg != null) {
+      omResponse.setMessage(errorMsg);
     }
     return omResponse.build();
   }
 
+  private String exceptionErrorMessage(IOException ex) {
+    if (ex instanceof OMException) {
+      return ex.getMessage();
+    } else {
+      return StringUtils.stringifyException(ex);
+    }
+  }
+
   /**
    * Submits request to OM's Ratis server.
    */