From cf09fbf4ce54443c78a40f529b124423ed1c5443 Mon Sep 17 00:00:00 2001
From: Gian Merlino <gian@imply.io>
Date: Sun, 26 May 2019 15:14:50 -0700
Subject: [PATCH] Fix LookupSerdeModule double-binding in
 Coordinator-as-Overlord mode. (#7765)

Fixes #7762.
---
 .../src/main/java/org/apache/druid/cli/CliCoordinator.java  | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/services/src/main/java/org/apache/druid/cli/CliCoordinator.java b/services/src/main/java/org/apache/druid/cli/CliCoordinator.java
index c1ab5b94a7d..98bb958d9c5 100644
--- a/services/src/main/java/org/apache/druid/cli/CliCoordinator.java
+++ b/services/src/main/java/org/apache/druid/cli/CliCoordinator.java
@@ -272,10 +272,12 @@ public class CliCoordinator extends ServerRunnable
         }
     );
 
-    modules.add(new LookupSerdeModule());
-
     if (beOverlord) {
       modules.addAll(new CliOverlord().getModules(false));
+    } else {
+      // Only add LookupSerdeModule if !beOverlord, since CliOverlord includes it, and having two copies causes
+      // the injector to get confused due to having multiple bindings for the same classes.
+      modules.add(new LookupSerdeModule());
     }
 
     return modules;