From d6c7d868cdb450c2d2064d324b3da124d2a491b6 Mon Sep 17 00:00:00 2001
From: Maytas Monsereenusorn <maytasm@apache.org>
Date: Sun, 16 Jun 2024 09:18:44 +0700
Subject: [PATCH] Fix peon startup with non string property value (#16612)

---
 .../druid/indexing/overlord/ForkingTaskRunner.java    | 11 +++++++----
 .../indexing/overlord/ForkingTaskRunnerTest.java      |  1 +
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/indexing-service/src/main/java/org/apache/druid/indexing/overlord/ForkingTaskRunner.java b/indexing-service/src/main/java/org/apache/druid/indexing/overlord/ForkingTaskRunner.java
index e946fc6149b..c676877c110 100644
--- a/indexing-service/src/main/java/org/apache/druid/indexing/overlord/ForkingTaskRunner.java
+++ b/indexing-service/src/main/java/org/apache/druid/indexing/overlord/ForkingTaskRunner.java
@@ -314,10 +314,13 @@ public class ForkingTaskRunner
                         if (context != null) {
                           for (String propName : context.keySet()) {
                             if (propName.startsWith(CHILD_PROPERTY_PREFIX)) {
-                              command.addSystemProperty(
-                                  propName.substring(CHILD_PROPERTY_PREFIX.length()),
-                                  task.getContextValue(propName)
-                              );
+                              Object contextValue = task.getContextValue(propName);
+                              if (contextValue != null) {
+                                command.addSystemProperty(
+                                    propName.substring(CHILD_PROPERTY_PREFIX.length()),
+                                    String.valueOf(contextValue)
+                                );
+                              }
                             }
                           }
                         }
diff --git a/indexing-service/src/test/java/org/apache/druid/indexing/overlord/ForkingTaskRunnerTest.java b/indexing-service/src/test/java/org/apache/druid/indexing/overlord/ForkingTaskRunnerTest.java
index 2c17b3cb7c4..56695e5cf27 100644
--- a/indexing-service/src/test/java/org/apache/druid/indexing/overlord/ForkingTaskRunnerTest.java
+++ b/indexing-service/src/test/java/org/apache/druid/indexing/overlord/ForkingTaskRunnerTest.java
@@ -392,6 +392,7 @@ public class ForkingTaskRunnerTest
                                + "  \"firehose\" : null,\n"
                                + "  \"context\" : {\n"
                                + "    \"druid.indexer.runner.javaOptsArray\" : [ \"-Xmx10g\", \"-Xms10g\" ],\n"
+                               + "    \"druid.indexer.fork.property.druid.processing.numThreads\" : 4,\n"
                                + "    \"druid.indexer.runner.javaOpts\" : \"-Xmx1g -Xms1g\"\n"
                                + "  }\n"
                                + "}";