From d459073f6122ea5162e6b5781dab933d0f4fb042 Mon Sep 17 00:00:00 2001
From: Andrzej Bialecki <ab@apache.org>
Date: Mon, 21 Aug 2017 18:45:19 +0200
Subject: [PATCH] SOLR-11270: Automatically added SystemLogListener should not
 prevent deleting a trigger.

---
 solr/CHANGES.txt                                       |  2 ++
 .../solr/cloud/autoscaling/AutoScalingHandler.java     | 10 +++++++++-
 .../solr/cloud/autoscaling/AutoScalingHandlerTest.java | 10 +---------
 3 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/solr/CHANGES.txt b/solr/CHANGES.txt
index e11f16fa14b..bd2d7a93ea0 100644
--- a/solr/CHANGES.txt
+++ b/solr/CHANGES.txt
@@ -180,6 +180,8 @@ Other Changes
 
 * SOLR-11249: Upgrade Jetty from 9.3.14.v20161028 to 9.3.20.v20170531 (Michael Braun via David Smiley)
 
+* SOLR-11270: Automatically added SystemLogListener should not prevent deleting a trigger. (ab)
+
 ==================  7.0.0 ==================
 
 Versions of Major Components
diff --git a/solr/core/src/java/org/apache/solr/cloud/autoscaling/AutoScalingHandler.java b/solr/core/src/java/org/apache/solr/cloud/autoscaling/AutoScalingHandler.java
index abd85cfa0da..a5d1bc7dd64 100644
--- a/solr/core/src/java/org/apache/solr/cloud/autoscaling/AutoScalingHandler.java
+++ b/solr/core/src/java/org/apache/solr/cloud/autoscaling/AutoScalingHandler.java
@@ -601,7 +601,15 @@ public class AutoScalingHandler extends RequestHandlerBase implements Permission
       }
     }
     if (!activeListeners.isEmpty()) {
-      if (removeListeners) {
+      boolean onlySystemLog = false;
+      if (activeListeners.size() == 1) {
+        AutoScalingConfig.TriggerListenerConfig cfg = listeners.get(activeListeners.iterator().next());
+        if (SystemLogListener.class.getName().equals(cfg.listenerClass) ||
+            ("solr." + SystemLogListener.class.getSimpleName()).equals(cfg.listenerClass)) {
+          onlySystemLog = true;
+        }
+      }
+      if (removeListeners || onlySystemLog) {
         listeners = new HashMap<>(listeners);
         listeners.keySet().removeAll(activeListeners);
       } else {
diff --git a/solr/core/src/test/org/apache/solr/cloud/autoscaling/AutoScalingHandlerTest.java b/solr/core/src/test/org/apache/solr/cloud/autoscaling/AutoScalingHandlerTest.java
index 79879e8bb63..335fdbc307b 100644
--- a/solr/core/src/test/org/apache/solr/cloud/autoscaling/AutoScalingHandlerTest.java
+++ b/solr/core/src/test/org/apache/solr/cloud/autoscaling/AutoScalingHandlerTest.java
@@ -355,22 +355,14 @@ public class AutoScalingHandlerTest extends SolrCloudTestCase {
         "\t\t\"name\" : \"xyz\"\n" +
         "\t}\n" +
         "}";
-    String removeListenerCommand1 = "{\n" +
-        "\t\"remove-listener\" : {\n" +
-        "\t\t\"name\" : \"node_lost_trigger.system\"\n" +
-        "\t}\n" +
-        "}";
     req = createAutoScalingRequest(SolrRequest.METHOD.POST, removeListenerCommand);
     response = solrClient.request(req);
     assertEquals(response.get("result").toString(), "success");
-    req = createAutoScalingRequest(SolrRequest.METHOD.POST, removeListenerCommand1);
-    response = solrClient.request(req);
-    assertEquals(response.get("result").toString(), "success");
     data = zkClient().getData(SOLR_AUTOSCALING_CONF_PATH, null, null, true);
     loaded = ZkNodeProps.load(data);
     listeners = (Map<String, Object>) loaded.get("listeners");
     assertNotNull(listeners);
-    assertEquals(0, listeners.size());
+    assertEquals(1, listeners.size());
 
     removeTriggerCommand = "{" +
         "'remove-trigger' : {" +