From 616ae631c62a98d2145af0a87a0e2ab3af199d1f Mon Sep 17 00:00:00 2001
From: Kashif Faraz <kashif.faraz@gmail.com>
Date: Tue, 9 Jul 2024 23:51:52 -0700
Subject: [PATCH] Fix NPE in CompactSegments (#16713)

---
 .../druid/server/coordinator/duty/CompactSegments.java       | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/server/src/main/java/org/apache/druid/server/coordinator/duty/CompactSegments.java b/server/src/main/java/org/apache/druid/server/coordinator/duty/CompactSegments.java
index 27f6d17638d..335912fe23e 100644
--- a/server/src/main/java/org/apache/druid/server/coordinator/duty/CompactSegments.java
+++ b/server/src/main/java/org/apache/druid/server/coordinator/duty/CompactSegments.java
@@ -234,12 +234,13 @@ public class CompactSegments implements CoordinatorCustomDuty
     Granularity configuredSegmentGranularity = dataSourceCompactionConfig.getGranularitySpec()
                                                                          .getSegmentGranularity();
     Granularity taskSegmentGranularity = compactionTaskQuery.getGranularitySpec().getSegmentGranularity();
-    if (configuredSegmentGranularity.equals(taskSegmentGranularity)) {
+    if (configuredSegmentGranularity == null
+        || configuredSegmentGranularity.equals(taskSegmentGranularity)) {
       return false;
     }
 
     LOG.info(
-        "Cancelling task [%s] as task segmentGranularity is [%s] but compaction config segmentGranularity is [%s]",
+        "Cancelling task[%s] as task segmentGranularity[%s] differs from compaction config segmentGranularity[%s].",
         compactionTaskQuery.getId(), taskSegmentGranularity, configuredSegmentGranularity
     );
     overlordClient.cancelTask(compactionTaskQuery.getId());