SharedDiscoveryService works with refuseToBeLeader

Topologies are bootstrapped by the first server that does not refuse to be leader. The bootstrapping member must become leader to upload the snapshot to the other members. This logic also exists in HazelcastClusterTopology, but is coupled with the underlying data structures in a way that is hard to extract.
neo4j · Feb 6, 2018 · 3997e28 · 3997e28
1 parent dd114f8
commit 3997e28
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Showing 4 changed files with 20 additions and 12 deletions.
diff --git a/...ustering/src/main/java/org/neo4j/causalclustering/discovery/HazelcastClusterTopology.java b/...ustering/src/main/java/org/neo4j/causalclustering/discovery/HazelcastClusterTopology.java
@@ -188,14 +188,7 @@ private static boolean canBeBootstrapped( HazelcastInstance hazelcastInstance, C
             {
                 if ( !member.getBooleanAttribute( REFUSE_TO_BE_LEADER_KEY ) )
                 {
-                    if ( member.localMember() )
-                    {
-                        return true;
-                    }
-                    else
-                    {
-                        return false;
-                    }
+                    return member.localMember();
                 }
             }
             return false;

diff --git a/...stering/src/test/java/org/neo4j/causalclustering/discovery/SharedDiscoveryCoreClient.java b/...stering/src/test/java/org/neo4j/causalclustering/discovery/SharedDiscoveryCoreClient.java
@@ -24,6 +24,7 @@
 import java.util.Set;
 
 import org.neo4j.causalclustering.core.CausalClusteringSettings;
+import org.neo4j.causalclustering.core.state.RefuseToBeLeaderStrategy;
 import org.neo4j.causalclustering.identity.ClusterId;
 import org.neo4j.causalclustering.identity.MemberId;
 import org.neo4j.helpers.AdvertisedSocketAddress;
@@ -39,6 +40,7 @@ class SharedDiscoveryCoreClient extends LifecycleAdapter implements CoreTopology
     private final CoreServerInfo coreServerInfo;
     private final Set<Listener> listeners = new LinkedHashSet<>();
     private final Log log;
+    private final boolean refusesToBeLeader;
 
     private CoreTopology coreTopology;
     private ReadReplicaTopology readReplicaTopology;
@@ -49,6 +51,7 @@ class SharedDiscoveryCoreClient extends LifecycleAdapter implements CoreTopology
         this.member = member;
         this.coreServerInfo = extractCoreServerInfo( config );
         this.log = logProvider.getLog( getClass() );
+        this.refusesToBeLeader = RefuseToBeLeaderStrategy.shouldRefuseToBeLeader( config );
     }
 
     @Override
@@ -125,4 +128,9 @@ private static CoreServerInfo extractCoreServerInfo( Config config )
 
         return new CoreServerInfo( raftAddress, transactionSource, clientConnectorAddresses );
     }
+
+    public boolean refusesToBeLeader()
+    {
+        return refusesToBeLeader;
+    }
 }
diff --git a/...clustering/src/test/java/org/neo4j/causalclustering/discovery/SharedDiscoveryService.java b/...clustering/src/test/java/org/neo4j/causalclustering/discovery/SharedDiscoveryService.java
@@ -88,15 +88,24 @@ CoreTopology coreTopology( SharedDiscoveryCoreClient client )
         lock.lock();
         try
         {
-            return new CoreTopology( clusterId, coreClients.size() > 0 && coreClients.get( 0 ) == client,
-                    unmodifiableMap( coreMembers ) );
+            return new CoreTopology( clusterId, canBeBootstrapped( client ), unmodifiableMap( coreMembers ) );
         }
         finally
         {
             lock.unlock();
         }
     }
 
+    private boolean canBeBootstrapped( SharedDiscoveryCoreClient client )
+    {
+        return client != null && coreClients.size() > 0 &&
+                coreClients.stream()
+                        .filter( core -> !core.refusesToBeLeader() )
+                        .findFirst()
+                        .map( client::equals )
+                        .orElse( false );
+    }
+
     ReadReplicaTopology readReplicaTopology()
     {
         lock.lock();

diff --git a/...e/causal-clustering/src/test/java/org/neo4j/causalclustering/scenarios/PreElectionIT.java b/...e/causal-clustering/src/test/java/org/neo4j/causalclustering/scenarios/PreElectionIT.java
@@ -33,7 +33,6 @@
 import org.neo4j.causalclustering.core.consensus.roles.Role;
 import org.neo4j.causalclustering.discovery.Cluster;
 import org.neo4j.causalclustering.discovery.CoreClusterMember;
-import org.neo4j.causalclustering.discovery.HazelcastDiscoveryServiceFactory;
 import org.neo4j.test.Race;
 import org.neo4j.test.assertion.Assert;
 import org.neo4j.test.causalclustering.ClusterRule;
@@ -142,7 +141,6 @@ public void shouldElectANewLeaderIfAServerRefusesToBeLeader() throws Exception
     {
         // given
         clusterRule
-                .withDiscoveryServiceFactory( new HazelcastDiscoveryServiceFactory() )
                 .withInstanceCoreParam( CausalClusteringSettings.refuse_to_be_leader, this::firstServerRefusesToBeLeader )
                 .withSharedCoreParam( CausalClusteringSettings.multi_dc_license, "true" );
         Cluster cluster = clusterRule.startCluster();