Re-use helper.

Signed-off-by: Finn Carroll <carrofin@amazon.com>

Author: finnegancarroll

legacy/src/main/java/org/opensearch/sql/legacy/plugin/RestSqlAction.java

@@ -210,7 +210,7 @@ private void handleException(RestChannel restChannel, Exception exception) {
     reportError(restChannel, exception, status);
   }
 
-  private static RestStatus getRestStatus(Exception ex) {
+  public static RestStatus getRestStatus(Exception ex) {
     int code = getRawErrorCode(ex);
     return RestStatus.fromCode(code);
   }

plugin/src/main/java/org/opensearch/sql/plugin/SQLPlugin.java

@@ -263,11 +263,8 @@ protected Object buildJsonObject(ExplainResponse resp) {
 
               @Override
               public void onFailure(Exception e) {
-                RestStatus status =
-                    (e instanceof org.opensearch.OpenSearchException osEx)
-                        ? osEx.status()
-                        : RestStatus.INTERNAL_SERVER_ERROR;
-                channel.sendResponse(new BytesRestResponse(status, e.getMessage()));
+                channel.sendResponse(
+                    new BytesRestResponse(RestSqlAction.getRestStatus(e), e.getMessage()));
               }
             });
       } else {
@@ -285,11 +282,8 @@ public void onResponse(TransportPPLQueryResponse response) {
 
               @Override
               public void onFailure(Exception e) {
-                RestStatus status =
-                    (e instanceof org.opensearch.OpenSearchException osEx)
-                        ? osEx.status()
-                        : RestStatus.INTERNAL_SERVER_ERROR;
-                channel.sendResponse(new BytesRestResponse(status, e.getMessage()));
+                channel.sendResponse(
+                    new BytesRestResponse(RestSqlAction.getRestStatus(e), e.getMessage()));
               }
             });
       }