TINKERPOP-1044: Standardized Message Format and Added Extra HTTP Header for the exception class instead of making a message with multiple lines

Author: Vivek Krishnan

gremlin-server/src/main/java/org/apache/tinkerpop/gremlin/server/handler/HttpGremlinEndpointHandler.java

@@ -254,18 +254,9 @@ public void channelRead(final ChannelHandlerContext ctx, final Object msg) {
 
                 evalFuture.exceptionally(t -> {
 
-					if (t.getMessage() != null) {
-						sendError(ctx, INTERNAL_SERVER_ERROR,
-								String.format("Error encountered evaluating script: %s\nExecution Interrupted by %s\nMessage: %s", 
-											  requestArguments.getValue0(), t.getClass().getName(), t.getMessage()),
-								Optional.of(t));
-                    } else {
-						sendError(ctx, INTERNAL_SERVER_ERROR,
-								String.format("Error encountered evaluating script: %s\nExecution Interrupted by %s", 
-											  requestArguments.getValue0(), t.getClass().getName()),
-								Optional.of(t));
-					}
-					
+					String errorMessage = (t.getMessage() != null) ? t.getMessage() : 
+										String.format("Error encountered evaluating script: %s", requestArguments.getValue0());
+					sendError(ctx, INTERNAL_SERVER_ERROR, errorMessage, Optional.of(t));
                     promise.setFailure(t);
                     return null;
                 });
@@ -465,6 +456,11 @@ private static void sendError(final ChannelHandlerContext ctx, final HttpRespons
         errorMeter.mark();
         final ObjectNode node = mapper.createObjectNode();
         node.put("message", message);
+		if (t.isPresent()){
+			node.put("Exception-Class", t.get().getClass().getName());
+		}
+		
+		
         final FullHttpResponse response = new DefaultFullHttpResponse(
                 HTTP_1_1, status, Unpooled.copiedBuffer(node.toString(), CharsetUtil.UTF_8));
         response.headers().set(CONTENT_TYPE, "application/json");