From e9f5658f9eb2b31f68bff8aba7f9f3f8a8166e04 Mon Sep 17 00:00:00 2001
From: Niketh Sabbineni <niketh.sabbineni@gmail.com>
Date: Tue, 13 Mar 2018 16:55:00 -0700
Subject: [PATCH] Query should not fail because emitter fails or throws
 Exception

---
 .../io/druid/query/MetricsEmittingQueryRunner.java     | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/processing/src/main/java/io/druid/query/MetricsEmittingQueryRunner.java b/processing/src/main/java/io/druid/query/MetricsEmittingQueryRunner.java
index 0734c2b6a948..be68a24ca1e9 100644
--- a/processing/src/main/java/io/druid/query/MetricsEmittingQueryRunner.java
+++ b/processing/src/main/java/io/druid/query/MetricsEmittingQueryRunner.java
@@ -19,6 +19,7 @@
 
 package io.druid.query;
 
+import io.druid.java.util.common.logger.Logger;
 import io.druid.java.util.emitter.service.ServiceEmitter;
 import io.druid.java.util.common.guava.LazySequence;
 import io.druid.java.util.common.guava.Sequence;
@@ -39,6 +40,7 @@ public class MetricsEmittingQueryRunner<T> implements QueryRunner<T>
   private final long creationTimeNs;
   private final ObjLongConsumer<? super QueryMetrics<?>> reportMetric;
   private final Consumer<QueryMetrics<?>> applyCustomDimensions;
+  private static final Logger log = new Logger(MetricsEmittingQueryRunner.class);
 
   private MetricsEmittingQueryRunner(
       ServiceEmitter emitter,
@@ -117,7 +119,13 @@ public void after(boolean isDone, Throwable thrown)
             if (creationTimeNs > 0) {
               queryMetrics.reportWaitTime(startTimeNs - creationTimeNs);
             }
-            queryMetrics.emit(emitter);
+            try {
+              queryMetrics.emit(emitter);
+            }
+            catch (Exception e) {
+              // Query should not fail, because of emitter failure. Swallowing the exception.
+              log.error("Failure while trying to emit [%s] with stacktrace [%s]", emitter.toString(), e);
+            }
           }
         }
     );