Revert "HBASE-24743 Reject to add a peer which replicate to itself ea…

…rlier (#2071)"

This reverts commit 5db3ec2.

TestReplicationAdmin and TestReplicationShell are broken on branch-2 and master respectively

hbase-server/src/main/java/org/apache/hadoop/hbase/master/HMaster.java

@@ -801,7 +801,7 @@ protected void initializeZKBasedSystemTrackers()
     this.splitOrMergeTracker = new SplitOrMergeTracker(zooKeeper, conf, this);
     this.splitOrMergeTracker.start();
 
-    this.replicationPeerManager = ReplicationPeerManager.create(zooKeeper, conf, clusterId);
+    this.replicationPeerManager = ReplicationPeerManager.create(zooKeeper, conf);
 
     this.drainingServerTracker = new DrainingServerTracker(zooKeeper, this, this.serverManager);
     this.drainingServerTracker.start();

hbase-server/src/main/java/org/apache/hadoop/hbase/master/replication/ReplicationPeerManager.java

@@ -31,7 +31,6 @@
 import org.apache.commons.lang3.StringUtils;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
-import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.replication.BaseReplicationEndpoint;
@@ -46,11 +45,9 @@
 import org.apache.hadoop.hbase.replication.ReplicationStorageFactory;
 import org.apache.hadoop.hbase.replication.ReplicationUtils;
 import org.apache.hadoop.hbase.replication.regionserver.HBaseInterClusterReplicationEndpoint;
-import org.apache.hadoop.hbase.zookeeper.ZKClusterId;
 import org.apache.hadoop.hbase.zookeeper.ZKConfig;
 import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
-import org.apache.zookeeper.KeeperException;
 
 /**
  * Manages and performs all replication admin operations.
@@ -66,17 +63,11 @@ public class ReplicationPeerManager {
 
   private final ConcurrentMap<String, ReplicationPeerDescription> peers;
 
-  private final String clusterId;
-
-  private final Configuration conf;
-
   ReplicationPeerManager(ReplicationPeerStorage peerStorage, ReplicationQueueStorage queueStorage,
-    ConcurrentMap<String, ReplicationPeerDescription> peers, Configuration conf, String clusterId) {
+      ConcurrentMap<String, ReplicationPeerDescription> peers) {
     this.peerStorage = peerStorage;
     this.queueStorage = queueStorage;
     this.peers = peers;
-    this.conf = conf;
-    this.clusterId = clusterId;
   }
 
   private void checkQueuesDeleted(String peerId)
@@ -254,26 +245,26 @@ void removeAllQueuesAndHFileRefs(String peerId) throws ReplicationException {
 
   private void checkPeerConfig(ReplicationPeerConfig peerConfig) throws DoNotRetryIOException {
     String replicationEndpointImpl = peerConfig.getReplicationEndpointImpl();
-    ReplicationEndpoint endpoint = null;
+    boolean checkClusterKey = true;
     if (!StringUtils.isBlank(replicationEndpointImpl)) {
+      // try creating a instance
+      ReplicationEndpoint endpoint;
       try {
-        // try creating a instance
         endpoint = Class.forName(replicationEndpointImpl)
           .asSubclass(ReplicationEndpoint.class).getDeclaredConstructor().newInstance();
       } catch (Throwable e) {
         throw new DoNotRetryIOException(
           "Can not instantiate configured replication endpoint class=" + replicationEndpointImpl,
           e);
       }
+      // do not check cluster key if we are not HBaseInterClusterReplicationEndpoint
+      if (!(endpoint instanceof HBaseInterClusterReplicationEndpoint)) {
+        checkClusterKey = false;
+      }
     }
-    // Default is HBaseInterClusterReplicationEndpoint and only it need to check cluster key
-    if (endpoint == null || endpoint instanceof HBaseInterClusterReplicationEndpoint) {
+    if (checkClusterKey) {
       checkClusterKey(peerConfig.getClusterKey());
     }
-    // Default is HBaseInterClusterReplicationEndpoint which cannot replicate to same cluster
-    if (endpoint == null || !endpoint.canReplicateToSameCluster()) {
-      checkClusterId(peerConfig.getClusterKey());
-    }
 
     if (peerConfig.replicateAllUserTables()) {
       // If replicate_all flag is true, it means all user tables will be replicated to peer cluster.
@@ -366,25 +357,6 @@ private void checkClusterKey(String clusterKey) throws DoNotRetryIOException {
     }
   }
 
-  private void checkClusterId(String clusterKey) throws DoNotRetryIOException {
-    String peerClusterId = "";
-    try {
-      // Create the peer cluster config for get peer cluster id
-      Configuration peerConf = HBaseConfiguration.createClusterConf(conf, clusterKey);
-      try (ZKWatcher zkWatcher = new ZKWatcher(peerConf, this + "check-peer-cluster-id", null)) {
-        peerClusterId = ZKClusterId.readClusterIdZNode(zkWatcher);
-      }
-    } catch (IOException | KeeperException e) {
-      throw new DoNotRetryIOException("Can't get peerClusterId for clusterKey=" + clusterKey, e);
-    }
-    // In rare case, zookeeper setting may be messed up. That leads to the incorrect
-    // peerClusterId value, which is the same as the source clusterId
-    if (clusterId.equals(peerClusterId)) {
-      throw new DoNotRetryIOException("Invalid cluster key: " + clusterKey
-        + ", should not replicate to itself for HBaseInterClusterReplicationEndpoint");
-    }
-  }
-
   public List<String> getSerialPeerIdsBelongsTo(TableName tableName) {
     return peers.values().stream().filter(p -> p.getPeerConfig().isSerial())
       .filter(p -> p.getPeerConfig().needToReplicate(tableName)).map(p -> p.getPeerId())
@@ -395,7 +367,7 @@ public ReplicationQueueStorage getQueueStorage() {
     return queueStorage;
   }
 
-  public static ReplicationPeerManager create(ZKWatcher zk, Configuration conf, String clusterId)
+  public static ReplicationPeerManager create(ZKWatcher zk, Configuration conf)
       throws ReplicationException {
     ReplicationPeerStorage peerStorage =
       ReplicationStorageFactory.getReplicationPeerStorage(zk, conf);
@@ -406,7 +378,7 @@ public static ReplicationPeerManager create(ZKWatcher zk, Configuration conf, St
       peers.put(peerId, new ReplicationPeerDescription(peerId, enabled, peerConfig));
     }
     return new ReplicationPeerManager(peerStorage,
-      ReplicationStorageFactory.getReplicationQueueStorage(zk, conf), peers, conf, clusterId);
+      ReplicationStorageFactory.getReplicationQueueStorage(zk, conf), peers);
   }
 
   /**

hbase-server/src/main/java/org/apache/hadoop/hbase/replication/regionserver/ReplicationSource.java

@@ -524,6 +524,16 @@ private void initialize() {
     if (!this.isSourceActive()) {
       return;
     }
+
+    // In rare case, zookeeper setting may be messed up. That leads to the incorrect
+    // peerClusterId value, which is the same as the source clusterId
+    if (clusterId.equals(peerClusterId) && !replicationEndpoint.canReplicateToSameCluster()) {
+      this.terminate("ClusterId " + clusterId + " is replicating to itself: peerClusterId "
+          + peerClusterId + " which is not allowed by ReplicationEndpoint:"
+          + replicationEndpoint.getClass().getName(), null, false);
+      this.manager.removeSource(this);
+      return;
+    }
     LOG.info("{} Source: {}, is now replicating from cluster: {}; to peer cluster: {};",
       logPeerId(), this.replicationQueueInfo.getQueueId(), clusterId, peerClusterId);
 

hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestAsyncReplicationAdminApi.java

@@ -71,9 +71,9 @@ public class TestAsyncReplicationAdminApi extends TestAsyncAdminBase {
     HBaseClassTestRule.forClass(TestAsyncReplicationAdminApi.class);
 
   private final String ID_ONE = "1";
-  private static String KEY_ONE;
+  private final String KEY_ONE = "127.0.0.1:2181:/hbase";
   private final String ID_TWO = "2";
-  private static String KEY_TWO;
+  private final String KEY_TWO = "127.0.0.1:2181:/hbase2";
 
   @BeforeClass
   public static void setUpBeforeClass() throws Exception {
@@ -82,8 +82,6 @@ public static void setUpBeforeClass() throws Exception {
     TEST_UTIL.getConfiguration().setInt(HConstants.HBASE_CLIENT_RETRIES_NUMBER, 2);
     TEST_UTIL.getConfiguration().setInt(START_LOG_ERRORS_AFTER_COUNT_KEY, 0);
     TEST_UTIL.startMiniCluster();
-    KEY_ONE = TEST_UTIL.getClusterKey() + "-test1";
-    KEY_TWO = TEST_UTIL.getClusterKey() + "-test2";
     ASYNC_CONN = ConnectionFactory.createAsyncConnection(TEST_UTIL.getConfiguration()).get();
   }
 

hbase-server/src/test/java/org/apache/hadoop/hbase/replication/SerialReplicationTestBase.java

@@ -113,11 +113,6 @@ protected void doStart() {
     protected void doStop() {
       notifyStopped();
     }
-
-    @Override
-    public boolean canReplicateToSameCluster() {
-      return true;
-    }
   }
 
   @BeforeClass

hbase-server/src/test/java/org/apache/hadoop/hbase/replication/TestMasterReplication.java

@@ -25,6 +25,7 @@
 import java.io.Closeable;
 import java.io.IOException;
 import java.util.Arrays;
+import java.util.EnumSet;
 import java.util.List;
 import java.util.Optional;
 import java.util.Random;
@@ -33,14 +34,17 @@
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.Cell;
-import org.apache.hadoop.hbase.DoNotRetryIOException;
+import org.apache.hadoop.hbase.ClusterMetrics;
 import org.apache.hadoop.hbase.HBaseClassTestRule;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.HBaseTestingUtility;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.MiniHBaseCluster;
+import org.apache.hadoop.hbase.ServerMetrics;
+import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.Waiter;
 import org.apache.hadoop.hbase.client.Admin;
 import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder;
 import org.apache.hadoop.hbase.client.ConnectionFactory;
@@ -68,7 +72,9 @@
 import org.apache.hadoop.hbase.util.HFileTestUtil;
 import org.apache.hadoop.hbase.wal.WALEdit;
 import org.apache.hadoop.hbase.zookeeper.MiniZooKeeperCluster;
+import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.ClassRule;
@@ -170,16 +176,40 @@ public void testCyclicReplication1() throws Exception {
 
   /**
    * Tests the replication scenario 0 -> 0. By default
-   * {@link org.apache.hadoop.hbase.replication.regionserver.HBaseInterClusterReplicationEndpoint},
-   * the replication peer should not be added.
+   * {@link BaseReplicationEndpoint#canReplicateToSameCluster()} returns false, so the
+   * ReplicationSource should terminate, and no further logs should get enqueued
    */
-  @Test(expected = DoNotRetryIOException.class)
-  public void testLoopedReplication()
-    throws Exception {
+  @Test
+  public void testLoopedReplication() throws Exception {
     LOG.info("testLoopedReplication");
     startMiniClusters(1);
     createTableOnClusters(table);
     addPeer("1", 0, 0);
+    Thread.sleep(SLEEP_TIME);
+
+    // wait for source to terminate
+    final ServerName rsName = utilities[0].getHBaseCluster().getRegionServer(0).getServerName();
+    Waiter.waitFor(baseConfiguration, 10000, new Waiter.Predicate<Exception>() {
+      @Override
+      public boolean evaluate() throws Exception {
+        ClusterMetrics clusterStatus = utilities[0].getAdmin()
+            .getClusterMetrics(EnumSet.of(ClusterMetrics.Option.LIVE_SERVERS));
+        ServerMetrics serverLoad = clusterStatus.getLiveServerMetrics().get(rsName);
+        List<ReplicationLoadSource> replicationLoadSourceList =
+            serverLoad.getReplicationLoadSourceList();
+        return replicationLoadSourceList.isEmpty();
+      }
+    });
+
+    Table[] htables = getHTablesOnClusters(tableName);
+    putAndWait(row, famName, htables[0], htables[0]);
+    rollWALAndWait(utilities[0], table.getTableName(), row);
+    ZKWatcher zkw = utilities[0].getZooKeeperWatcher();
+    String queuesZnode = ZNodePaths.joinZNode(zkw.getZNodePaths().baseZNode,
+      ZNodePaths.joinZNode("replication", "rs"));
+    List<String> listChildrenNoWatch =
+        ZKUtil.listChildrenNoWatch(zkw, ZNodePaths.joinZNode(queuesZnode, rsName.toString()));
+    assertEquals(0, listChildrenNoWatch.size());
   }
 
   /**

hbase-server/src/test/java/org/apache/hadoop/hbase/replication/TestReplicationEndpoint.java

@@ -500,11 +500,6 @@ protected void doStop() {
       stoppedCount.incrementAndGet();
       notifyStopped();
     }
-
-    @Override
-    public boolean canReplicateToSameCluster() {
-      return true;
-    }
   }
 
   public static class InterClusterReplicationEndpointForTest

hbase-server/src/test/java/org/apache/hadoop/hbase/replication/regionserver/TestRaceWhenCreatingReplicationSource.java

@@ -127,11 +127,6 @@ protected void doStart() {
     protected void doStop() {
       notifyStopped();
     }
-
-    @Override
-    public boolean canReplicateToSameCluster() {
-      return true;
-    }
   }
 
   @BeforeClass

hbase-server/src/test/java/org/apache/hadoop/hbase/util/TestHBaseFsckCleanReplicationBarriers.java

@@ -174,9 +174,8 @@ public void testCleanReplicationBarrierWithExistTable() throws Exception {
   }
 
   public static void createPeer() throws IOException {
-    ReplicationPeerConfig rpc =
-      ReplicationPeerConfig.newBuilder().setClusterKey(UTIL.getClusterKey() + "-test")
-        .setSerial(true).build();
+    ReplicationPeerConfig rpc = ReplicationPeerConfig.newBuilder()
+        .setClusterKey(UTIL.getClusterKey()).setSerial(true).build();
     UTIL.getAdmin().addReplicationPeer(PEER_1, rpc);
     UTIL.getAdmin().addReplicationPeer(PEER_2, rpc);
   }