SOLR-6591: Overseer can use stale cluster state and lose updates for collections with stateFormat > 1

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1634243 13f79535-47bb-0310-9956-ffa450edef68

solr/CHANGES.txt

@@ -267,6 +267,9 @@ Bug Fixes
 
 * SOLR-6647: Bad error message when missing resource from ZK when parsing Schema (janhoy)
 
+* SOLR-6591: Overseer can use stale cluster state and lose updates for collections
+  with stateFormat > 1. (shalin)
+
 Optimizations
 ----------------------
 

solr/core/src/test/org/apache/solr/cloud/CollectionsAPIDistributedZkTest.java

@@ -1039,18 +1039,9 @@ public class CollectionsAPIDistributedZkTest extends AbstractFullDistribZkTestBa
                 "conf1");
             
             // remove collection
-            ModifiableSolrParams params = new ModifiableSolrParams();
+            CollectionAdminRequest.Delete delete = new CollectionAdminRequest.Delete();
-            params.set("action", CollectionAction.DELETE.toString());
+            delete.setCollectionName(collectionName);
-            params.set("name", collectionName);
+            client.request(delete);
-            QueryRequest request = new QueryRequest(params);
-            request.setPath("/admin/collections");
-            
-            if (client == null) {
-              client = createCloudClient(null);
-            }
-            
-            client.request(request);
-            
           } catch (SolrServerException e) {
             e.printStackTrace();
             throw new RuntimeException(e);

solr/core/src/test/org/apache/solr/cloud/SimpleCollectionCreateDeleteTest.java

@@ -0,0 +1,82 @@
+package org.apache.solr.cloud;
+
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import org.apache.solr.client.solrj.impl.CloudSolrServer;
+import org.apache.solr.client.solrj.request.CollectionAdminRequest;
+import org.apache.solr.client.solrj.request.QueryRequest;
+import org.apache.solr.common.cloud.SolrZkClient;
+import org.apache.solr.common.cloud.ZkStateReader;
+import org.apache.solr.common.params.ModifiableSolrParams;
+import org.apache.solr.common.params.SolrParams;
+import org.apache.solr.common.util.NamedList;
+
+public class SimpleCollectionCreateDeleteTest extends AbstractFullDistribZkTestBase {
+
+  public SimpleCollectionCreateDeleteTest() {
+    fixShardCount = true;
+    sliceCount = 1;
+    shardCount = 1;
+  }
+
+  @Override
+  public void doTest() throws Exception {
+    String overseerNode = OverseerCollectionProcessor.getLeaderNode(cloudClient.getZkStateReader().getZkClient());
+    String notOverseerNode = null;
+    for (CloudJettyRunner cloudJetty : cloudJettys) {
+      if (!overseerNode.equals(cloudJetty.nodeName)) {
+        notOverseerNode = cloudJetty.nodeName;
+        break;
+      }
+    }
+    CollectionAdminRequest.Create create = new CollectionAdminRequest.Create();
+    String collectionName = "SimpleCollectionCreateDeleteTest";
+    create.setCollectionName(collectionName);
+    create.setNumShards(1);
+    create.setReplicationFactor(1);
+    create.setCreateNodeSet(overseerNode);
+    ModifiableSolrParams params = new ModifiableSolrParams(create.getParams());
+    params.set("stateFormat", "2");
+    QueryRequest req = new QueryRequest(params);
+    req.setPath("/admin/collections");
+    NamedList<Object> request = cloudClient.request(req);
+
+    if (request.get("success") != null) {
+      assertTrue(cloudClient.getZkStateReader().getZkClient().exists(ZkStateReader.COLLECTIONS_ZKNODE + "/" + collectionName, false));
+
+      CollectionAdminRequest.Delete delete = new CollectionAdminRequest.Delete();
+      delete.setCollectionName(collectionName);
+      cloudClient.request(delete);
+
+      assertFalse(cloudClient.getZkStateReader().getZkClient().exists(ZkStateReader.COLLECTIONS_ZKNODE + "/" + collectionName, false));
+
+      // create collection again on a node other than the overseer leader
+      create = new CollectionAdminRequest.Create();
+      create.setCollectionName(collectionName);
+      create.setNumShards(1);
+      create.setReplicationFactor(1);
+      create.setCreateNodeSet(notOverseerNode);
+      params = new ModifiableSolrParams(create.getParams());
+      params.set("stateFormat", "2");
+      req = new QueryRequest(params);
+      req.setPath("/admin/collections");
+      request = cloudClient.request(req);
+      assertTrue("Collection creation should not have failed", request.get("success") != null);
+    }
+  }
+}

solr/solrj/src/java/org/apache/solr/common/cloud/ZkStateReader.java

@@ -876,6 +876,7 @@ public class ZkStateReader implements Closeable {
   public void removeZKWatch(final String coll) {
     synchronized (this) {
       watchedCollections.remove(coll);
+      watchedCollectionStates.remove(coll);
       try {
         updateClusterState(true);
       } catch (KeeperException e) {