From 856b438fe87c22261dc7deabaa4d2629a59c94ea Mon Sep 17 00:00:00 2001 From: Umeshkumar9414 <9414umeshkumar@gmail.com> Date: Wed, 12 Aug 2026 01:52:32 +0530 Subject: [PATCH] HBASE-30323 Fix RegionMover to respect RSGroups in branch-2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RegionMover.unloadRegions() previously picked destination servers from all online RegionServers regardless of RSGroup membership, potentially trying to move regions out of their assigned group during server decommission, althoug HMaster prevents it. This is a branch-2-compatible port of HBASE-22740. On master/branch-3 the fix used admin.getRSGroup() which is integrated directly into the Admin interface (via HBASE-22971). On branch-2 RSGroup remains an optional coprocessor (RSGroupAdminEndpoint), so we: 1. Check for RSGroupAdminEndpoint via getMasterCoprocessorNames() to skip the RSGroup path on clusters that do not use RSGroups. 2. Call getRSGroupInfoOfServer() via the RSGroupAdminService coprocessor RPC, using the unshaded protobuf service from hbase-protocol. 3. Filter the destination server list to only servers in the same RSGroup (filterRSGroupServers); filtering is always applied by membership — the DEFAULT_GROUP short-circuit that could leak regions across groups is removed. 4. Log a DEBUG message when hasRSGroupInfo()==false to aid diagnosis of hostname-vs-IP address-form mismatches (HBASE-27304). RSGroupAdmin.proto is moved from hbase-rsgroup to hbase-protocol so that hbase-server can use RSGroupAdminService without creating a circular dependency with hbase-rsgroup. Both modules depended on the same generated FQN; consolidating in hbase-protocol (which both already depend on) is best I could think of. Tests: - TestRegionMoverWithRSGroupEnable (hbase-rsgroup): 5-node mini cluster integration test with RSGroupAdminEndpoint enabled. Verifies that unloading a non-default-group server places all regions exclusively on the remaining server in that group (positive assertion) and that no default-group server receives any of those regions (isolation assertion). Also tests the guard path: unloading a default-group server succeeds end-to-end when RSGroups are enabled. - TestRegionMoverFilterRSGroupServers (hbase-server): unit tests for filterRSGroupServers() — default group returns full server list, non-default group filters to members only, no-match group returns empty. Co-authored-by: Claude Sonnet 4.6 --- .../src/main/protobuf/RSGroupAdmin.proto | 0 .../TestRegionMoverWithRSGroupEnable.java | 252 ++++++++++++++++++ .../apache/hadoop/hbase/util/RegionMover.java | 65 ++++- .../TestRegionMoverFilterRSGroupServers.java | 129 +++++++++ 4 files changed, 445 insertions(+), 1 deletion(-) rename {hbase-rsgroup => hbase-protocol}/src/main/protobuf/RSGroupAdmin.proto (100%) create mode 100644 hbase-rsgroup/src/test/java/org/apache/hadoop/hbase/rsgroup/TestRegionMoverWithRSGroupEnable.java create mode 100644 hbase-server/src/test/java/org/apache/hadoop/hbase/util/TestRegionMoverFilterRSGroupServers.java diff --git a/hbase-rsgroup/src/main/protobuf/RSGroupAdmin.proto b/hbase-protocol/src/main/protobuf/RSGroupAdmin.proto similarity index 100% rename from hbase-rsgroup/src/main/protobuf/RSGroupAdmin.proto rename to hbase-protocol/src/main/protobuf/RSGroupAdmin.proto diff --git a/hbase-rsgroup/src/test/java/org/apache/hadoop/hbase/rsgroup/TestRegionMoverWithRSGroupEnable.java b/hbase-rsgroup/src/test/java/org/apache/hadoop/hbase/rsgroup/TestRegionMoverWithRSGroupEnable.java new file mode 100644 index 000000000000..e2842bbc7be0 --- /dev/null +++ b/hbase-rsgroup/src/test/java/org/apache/hadoop/hbase/rsgroup/TestRegionMoverWithRSGroupEnable.java @@ -0,0 +1,252 @@ +/* + * 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. + */ +package org.apache.hadoop.hbase.rsgroup; + +import static org.junit.jupiter.api.Assertions.assertEquals; +import static org.junit.jupiter.api.Assertions.assertTrue; + +import java.util.ArrayList; +import java.util.Arrays; +import java.util.Collection; +import java.util.HashSet; +import java.util.List; +import org.apache.hadoop.fs.Path; +import org.apache.hadoop.hbase.HBaseTestingUtility; +import org.apache.hadoop.hbase.HConstants; +import org.apache.hadoop.hbase.ServerName; +import org.apache.hadoop.hbase.TableName; +import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder; +import org.apache.hadoop.hbase.client.TableDescriptor; +import org.apache.hadoop.hbase.client.TableDescriptorBuilder; +import org.apache.hadoop.hbase.coprocessor.CoprocessorHost; +import org.apache.hadoop.hbase.master.ServerManager; +import org.apache.hadoop.hbase.net.Address; +import org.apache.hadoop.hbase.regionserver.HRegion; +import org.apache.hadoop.hbase.regionserver.HRegionServer; +import org.apache.hadoop.hbase.testclassification.MediumTests; +import org.apache.hadoop.hbase.testclassification.MiscTests; +import org.apache.hadoop.hbase.util.Bytes; +import org.apache.hadoop.hbase.util.JVMClusterUtil; +import org.apache.hadoop.hbase.util.RegionMover; +import org.apache.hadoop.hbase.util.RegionMover.RegionMoverBuilder; +import org.junit.jupiter.api.AfterAll; +import org.junit.jupiter.api.AfterEach; +import org.junit.jupiter.api.BeforeAll; +import org.junit.jupiter.api.BeforeEach; +import org.junit.jupiter.api.Tag; +import org.junit.jupiter.api.Test; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +/** + * Tests that RegionMover.unloadRegions() respects RSGroup membership in branch-2: regions + * decommissioned from a server in a non-default RSGroup must land only on other servers in the same + * group, not on servers in unrelated groups. + */ +@Tag(MiscTests.TAG) +@Tag(MediumTests.TAG) +public class TestRegionMoverWithRSGroupEnable { + + private static final Logger LOG = LoggerFactory.getLogger(TestRegionMoverWithRSGroupEnable.class); + + private static final HBaseTestingUtility TEST_UTIL = new HBaseTestingUtility(); + private static final String TEST_RSGROUP = "test"; + private static final TableName TABLE_NAME = TableName.valueOf("testRegionMoverWithRSGroupEnable"); + + @BeforeAll + public static void setUpBeforeClass() throws Exception { + TEST_UTIL.getConfiguration().set(HConstants.HBASE_MASTER_LOADBALANCER_CLASS, + RSGroupBasedLoadBalancer.class.getName()); + TEST_UTIL.getConfiguration().set(CoprocessorHost.MASTER_COPROCESSOR_CONF_KEY, + RSGroupAdminEndpoint.class.getName()); + TEST_UTIL.getConfiguration().setInt(ServerManager.WAIT_ON_REGIONSERVERS_MINTOSTART, 5); + TEST_UTIL.startMiniCluster(5); + } + + @AfterAll + public static void tearDownAfterClass() throws Exception { + TEST_UTIL.shutdownMiniCluster(); + } + + // Addresses of the two servers placed in TEST_RSGROUP each test. + private final List
rsservers = new ArrayList<>(2); + // Addresses of the servers that remain in the default group (excludes meta RS). + private final List defaultGroupServers = new ArrayList<>(); + private RSGroupAdminClient rsGroupAdmin; + + @BeforeEach + public void setUp() throws Exception { + rsGroupAdmin = new RSGroupAdminClient(TEST_UTIL.getConnection()); + if (rsGroupAdmin.getRSGroupInfo(TEST_RSGROUP) == null) { + rsGroupAdmin.addRSGroup(TEST_RSGROUP); + } + Collection allServers = TEST_UTIL.getAdmin().getRegionServers(); + + // Exclude the RS that hosts hbase:meta to keep the test stable. + ServerName rsContainMeta = TEST_UTIL.getMiniHBaseCluster().getRegionServerThreads().stream() + .map(JVMClusterUtil.RegionServerThread::getRegionServer) + .filter(rs -> !rs.getRegions(TableName.META_TABLE_NAME).isEmpty()).findFirst().get() + .getServerName(); + LOG.info("{} contains hbase:meta, keeping in default group", rsContainMeta); + + // Move any leftover servers back to default before setting up fresh assignments. + RSGroupInfo existingGroup = rsGroupAdmin.getRSGroupInfo(TEST_RSGROUP); + if (existingGroup != null && !existingGroup.getServers().isEmpty()) { + rsGroupAdmin.moveServers(new HashSet<>(existingGroup.getServers()), + RSGroupInfo.DEFAULT_GROUP); + } + + List modifiable = new ArrayList<>(allServers); + modifiable.remove(rsContainMeta); + int i = 0; + for (ServerName server : modifiable) { + if (i == 2) break; + rsservers.add(Address.fromParts(server.getHostname(), server.getPort())); + i++; + } + rsGroupAdmin.moveServers(new HashSet<>(rsservers), TEST_RSGROUP); + LOG.info("Servers moved to {} group: {}", TEST_RSGROUP, rsservers); + + assertEquals(3, rsGroupAdmin.getRSGroupInfo(RSGroupInfo.DEFAULT_GROUP).getServers().size()); + assertEquals(2, rsGroupAdmin.getRSGroupInfo(TEST_RSGROUP).getServers().size()); + + // Record the three default-group servers (used for isolation assertions). + for (ServerName sn : allServers) { + Address addr = sn.getAddress(); + if (!rsservers.contains(addr)) { + defaultGroupServers.add(sn); + } + } + + if (TEST_UTIL.getAdmin().tableExists(TABLE_NAME)) { + TEST_UTIL.deleteTable(TABLE_NAME); + } + TableDescriptor tableDesc = TableDescriptorBuilder.newBuilder(TABLE_NAME) + .setColumnFamily(ColumnFamilyDescriptorBuilder.of("f")).build(); + TEST_UTIL.getAdmin().createTable(tableDesc, Bytes.toBytes("a"), Bytes.toBytes("z"), 9); + rsGroupAdmin.moveTables(new HashSet<>(Arrays.asList(TABLE_NAME)), TEST_RSGROUP); + TEST_UTIL.waitTableAvailable(TABLE_NAME); + } + + @AfterEach + public void tearDown() throws Exception { + if (TEST_UTIL.getAdmin().tableExists(TABLE_NAME)) { + TEST_UTIL.deleteTable(TABLE_NAME); + } + if (!rsservers.isEmpty()) { + rsGroupAdmin.moveServers(new HashSet<>(rsservers), RSGroupInfo.DEFAULT_GROUP); + } + if (rsGroupAdmin.getRSGroupInfo(TEST_RSGROUP) != null) { + rsGroupAdmin.removeRSGroup(TEST_RSGROUP); + } + rsservers.clear(); + defaultGroupServers.clear(); + } + + /** + * Unloading a server in a non-default RSGroup must move all regions to the remaining server in + * that group — and must not move any region to a server in the default group. + */ + @Test + public void testUnloadRegionsRespectsRSGroup() throws Exception { + Address decommission = rsservers.get(0); + Address online = rsservers.get(1); + String filename = new Path(TEST_UTIL.getDataTestDir(), "testRSGroupUnload").toString(); + + RegionMoverBuilder builder = + new RegionMoverBuilder(decommission.toString(), TEST_UTIL.getConfiguration()); + try (RegionMover rm = builder.filename(filename).ack(true).build()) { + LOG.info("Unloading {}", decommission.getHostname()); + rm.unload(); + } + + HRegionServer onlineRS = TEST_UTIL.getMiniHBaseCluster().getRegionServerThreads().stream() + .map(JVMClusterUtil.RegionServerThread::getRegionServer) + .filter(rs -> rs.getServerName().getAddress().equals(online)).findFirst().get(); + + // Positive assertion: all 9 regions landed on the one remaining test-group server. + assertEquals(9, onlineRS.getNumberOfOnlineRegions(), + "All 9 regions must be on the single remaining server in the test RSGroup"); + + // Isolation assertion: no default-group server received any of the table's regions. + for (ServerName defaultSN : defaultGroupServers) { + HRegionServer defaultRS = TEST_UTIL.getMiniHBaseCluster().getRegionServerThreads().stream() + .map(JVMClusterUtil.RegionServerThread::getRegionServer) + .filter(rs -> rs.getServerName().equals(defaultSN)).findFirst().orElse(null); + if (defaultRS == null) continue; + List tableRegions = defaultRS.getRegions(TABLE_NAME); + assertTrue(tableRegions.isEmpty(), "Default-group server " + defaultSN + + " must not hold any regions of " + TABLE_NAME + " but had: " + tableRegions); + } + } + + /** + * Unloading a server that is in the default RSGroup must still succeed end-to-end when RSGroups + * are enabled. The server's regions should be spread across all available servers (not filtered). + */ + @Test + public void testUnloadDefaultGroupServerWithRSGroupEnabled() throws Exception { + ServerName defaultSN = defaultGroupServers.get(0); + Address decommission = defaultSN.getAddress(); + String filename = new Path(TEST_UTIL.getDataTestDir(), "testDefaultGroupUnload").toString(); + + // Create a table in the default group; the balancer will distribute its 6 regions naturally + // across the 3 default-group servers, so defaultSN will hold at least some. + TableName defaultTable = TableName.valueOf("testDefaultGroupTable"); + if (TEST_UTIL.getAdmin().tableExists(defaultTable)) { + TEST_UTIL.deleteTable(defaultTable); + } + try { + TableDescriptor td = TableDescriptorBuilder.newBuilder(defaultTable) + .setColumnFamily(ColumnFamilyDescriptorBuilder.of("f")).build(); + TEST_UTIL.getAdmin().createTable(td, Bytes.toBytes("a"), Bytes.toBytes("z"), 6); + TEST_UTIL.waitTableAvailable(defaultTable); + + RegionMoverBuilder builder = + new RegionMoverBuilder(decommission.toString(), TEST_UTIL.getConfiguration()); + try (RegionMover rm = builder.filename(filename).ack(true).build()) { + LOG.info("Unloading default-group server {}", decommission.getHostname()); + rm.unload(); + } + + // After unload, the decommissioned server must hold no regions of the default table. + HRegionServer decommRS = TEST_UTIL.getMiniHBaseCluster().getRegionServerThreads().stream() + .map(JVMClusterUtil.RegionServerThread::getRegionServer) + .filter(rs -> rs.getServerName().equals(defaultSN)).findFirst().get(); + assertEquals(0, decommRS.getRegions(defaultTable).size(), + "Decommissioned default-group server must hold no regions after unload"); + + // Isolation assertion: no test-group server must hold any region of the default table. + // RegionMover must have restricted move targets to the default group only. + for (JVMClusterUtil.RegionServerThread rst : TEST_UTIL.getMiniHBaseCluster() + .getRegionServerThreads()) { + HRegionServer rs = rst.getRegionServer(); + Address addr = rs.getServerName().getAddress(); + if (rsservers.contains(addr)) { + List found = rs.getRegions(defaultTable); + assertTrue(found.isEmpty(), "Test-group server " + addr + " must not hold any region of " + + defaultTable + " but had: " + found); + } + } + } finally { + if (TEST_UTIL.getAdmin().tableExists(defaultTable)) { + TEST_UTIL.deleteTable(defaultTable); + } + } + } +} diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/util/RegionMover.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/util/RegionMover.java index 6483cc78f4d8..405c32d36ede 100644 --- a/hbase-server/src/main/java/org/apache/hadoop/hbase/util/RegionMover.java +++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/util/RegionMover.java @@ -17,6 +17,7 @@ */ package org.apache.hadoop.hbase.util; +import com.google.protobuf.ServiceException; import java.io.BufferedInputStream; import java.io.BufferedOutputStream; import java.io.Closeable; @@ -31,6 +32,7 @@ import java.nio.file.Paths; import java.util.ArrayList; import java.util.Arrays; +import java.util.Collection; import java.util.Collections; import java.util.EnumSet; import java.util.HashSet; @@ -67,6 +69,14 @@ import org.apache.hadoop.hbase.master.RackManager; import org.apache.hadoop.hbase.master.RegionState; import org.apache.hadoop.hbase.master.assignment.AssignmentManager; +import org.apache.hadoop.hbase.net.Address; +import org.apache.hadoop.hbase.protobuf.ProtobufUtil; +import org.apache.hadoop.hbase.protobuf.generated.HBaseProtos; +import org.apache.hadoop.hbase.protobuf.generated.RSGroupAdminProtos.GetRSGroupInfoOfServerRequest; +import org.apache.hadoop.hbase.protobuf.generated.RSGroupAdminProtos.GetRSGroupInfoOfServerResponse; +import org.apache.hadoop.hbase.protobuf.generated.RSGroupAdminProtos.RSGroupAdminService; +import org.apache.hadoop.hbase.protobuf.generated.RSGroupProtos; +import org.apache.hadoop.hbase.rsgroup.RSGroupInfo; import org.apache.hadoop.hbase.zookeeper.MetaTableLocator; import org.apache.hadoop.hbase.zookeeper.ZKWatcher; import org.apache.hadoop.hbase.zookeeper.ZNodePaths; @@ -457,7 +467,13 @@ private boolean unloadRegions(boolean unloadFromRack, List isolateRegion try { // Get Online RegionServers List regionServers = new ArrayList<>(); - regionServers.addAll(admin.getRegionServers()); + RSGroupInfo rsgroup = getRSGroupInfo(hostname, port); + if (rsgroup != null) { + LOG.info("{} belongs to RSGroup {}", hostname, rsgroup.getName()); + regionServers.addAll(filterRSGroupServers(rsgroup, admin.getRegionServers())); + } else { + regionServers.addAll(admin.getRegionServers()); + } // Remove the host Region server from target Region Servers list ServerName server = stripServer(regionServers, hostname, port); if (server == null) { @@ -501,6 +517,8 @@ private boolean unloadRegions(boolean unloadFromRack, List isolateRegion if (regionServers.isEmpty()) { LOG.warn("No Regions were moved - no servers available"); return false; + } else { + LOG.info("Available servers {}", regionServers); } unloadRegions(server, regionServers, movedRegions, isolateRegionIdArray); } catch (Exception e) { @@ -838,6 +856,51 @@ private List readServersFromFile(String filename) throws IOException { return servers; } + /** + * Returns the {@link RSGroupInfo} for the given host:port if the RSGroup coprocessor is enabled + * on the cluster, or {@code null} if RSGroups are not in use. + */ + private RSGroupInfo getRSGroupInfo(String host, int port) throws IOException { + if (!admin.getMasterCoprocessorNames().contains("RSGroupAdminEndpoint")) { + return null; + } + RSGroupAdminService.BlockingInterface stub = + RSGroupAdminService.newBlockingStub(admin.coprocessorService()); + GetRSGroupInfoOfServerRequest request = GetRSGroupInfoOfServerRequest.newBuilder() + .setServer(HBaseProtos.ServerName.newBuilder().setHostName(host).setPort(port).build()) + .build(); + try { + GetRSGroupInfoOfServerResponse resp = stub.getRSGroupInfoOfServer(null, request); + if (!resp.hasRSGroupInfo()) { + LOG.debug("No RSGroup found for {}:{} — server may not be registered or address form " + + "(hostname vs IP) may not match what the RS registered with", host, port); + return null; + } + RSGroupProtos.RSGroupInfo proto = resp.getRSGroupInfo(); + // Only name and server membership are needed for filtering; tables/configuration are omitted. + RSGroupInfo rsGroupInfo = new RSGroupInfo(proto.getName()); + for (HBaseProtos.ServerName sn : proto.getServersList()) { + rsGroupInfo.addServer(Address.fromParts(sn.getHostName(), sn.getPort())); + } + return rsGroupInfo; + } catch (ServiceException e) { + throw ProtobufUtil.handleRemoteException(e); + } + } + + @InterfaceAudience.Private + Collection filterRSGroupServers(RSGroupInfo rsgroup, + Collection onlineServers) { + List result = new ArrayList<>(rsgroup.getServers().size()); + for (ServerName server : onlineServers) { + Address address = Address.fromParts(server.getHostname(), server.getPort()); + if (rsgroup.containsServer(address)) { + result.add(server); + } + } + return result; + } + /** * Designates or excludes the servername whose hostname and port portion matches the list given in * the file. Example:
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/util/TestRegionMoverFilterRSGroupServers.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/util/TestRegionMoverFilterRSGroupServers.java new file mode 100644 index 000000000000..add2cb083793 --- /dev/null +++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/util/TestRegionMoverFilterRSGroupServers.java @@ -0,0 +1,129 @@ +/* + * 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. + */ +package org.apache.hadoop.hbase.util; + +import static org.junit.jupiter.api.Assertions.assertEquals; +import static org.junit.jupiter.api.Assertions.assertTrue; + +import java.util.ArrayList; +import java.util.Collection; +import java.util.HashSet; +import java.util.List; +import java.util.Set; +import org.apache.hadoop.hbase.HBaseTestingUtility; +import org.apache.hadoop.hbase.ServerName; +import org.apache.hadoop.hbase.net.Address; +import org.apache.hadoop.hbase.rsgroup.RSGroupInfo; +import org.apache.hadoop.hbase.testclassification.MediumTests; +import org.apache.hadoop.hbase.testclassification.MiscTests; +import org.apache.hadoop.hbase.util.RegionMover.RegionMoverBuilder; +import org.junit.jupiter.api.AfterAll; +import org.junit.jupiter.api.Assertions; +import org.junit.jupiter.api.BeforeAll; +import org.junit.jupiter.api.Tag; +import org.junit.jupiter.api.Test; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +/** + * Unit tests for {@link RegionMover#filterRSGroupServers}. Spins up a 2-node mini cluster so we can + * build a real RegionMover instance; the method under test is pure in-memory logic. + */ +@Tag(MiscTests.TAG) +@Tag(MediumTests.TAG) +public class TestRegionMoverFilterRSGroupServers { + + private static final Logger LOG = + LoggerFactory.getLogger(TestRegionMoverFilterRSGroupServers.class); + + private static final HBaseTestingUtility TEST_UTIL = new HBaseTestingUtility(); + + @BeforeAll + public static void setUpBeforeClass() throws Exception { + TEST_UTIL.startMiniCluster(2); + } + + @AfterAll + public static void tearDownAfterClass() throws Exception { + TEST_UTIL.shutdownMiniCluster(); + } + + private RegionMover buildMover() throws Exception { + ServerName any = TEST_UTIL.getAdmin().getRegionServers().iterator().next(); + return new RegionMoverBuilder(any.getHostname() + ":" + any.getPort(), + TEST_UTIL.getConfiguration()).build(); + } + + /** + * When all online servers are members of the default group (as the coprocessor returns), the + * filter must return all of them — no server is dropped. + */ + @Test + public void testDefaultGroupReturnsAllServers() throws Exception { + try (RegionMover rm = buildMover()) { + List allServers = new ArrayList<>(TEST_UTIL.getAdmin().getRegionServers()); + + RSGroupInfo defaultGroup = new RSGroupInfo(RSGroupInfo.DEFAULT_GROUP); + for (ServerName sn : allServers) { + defaultGroup.addServer(Address.fromParts(sn.getHostname(), sn.getPort())); + } + + Collection result = rm.filterRSGroupServers(defaultGroup, allServers); + assertEquals(allServers.size(), result.size()); + assertTrue(result.containsAll(allServers)); + } + } + + /** A non-default group with one member must return only that member. */ + @Test + public void testNonDefaultGroupFiltersToMembers() throws Exception { + try (RegionMover rm = buildMover()) { + List allServers = new ArrayList<>(TEST_UTIL.getAdmin().getRegionServers()); + + ServerName member = allServers.get(0); + RSGroupInfo group = new RSGroupInfo("testgroup"); + group.addServer(Address.fromParts(member.getHostname(), member.getPort())); + + Collection result = rm.filterRSGroupServers(group, allServers); + assertEquals(1, result.size()); + assertTrue(result.contains(member)); + + RSGroupInfo defaultGroup = new RSGroupInfo(RSGroupInfo.DEFAULT_GROUP); + Set defaultGroupRs = + new HashSet<>(rm.filterRSGroupServers(defaultGroup, allServers)); + Assertions.assertFalse(defaultGroupRs.contains(member), + "Default group should not contain test group member"); + + } + } + + /** A non-default group with no matching members must return an empty list. */ + @Test + public void testNonDefaultGroupWithNoMatchReturnsEmpty() throws Exception { + try (RegionMover rm = buildMover()) { + List allServers = new ArrayList<>(TEST_UTIL.getAdmin().getRegionServers()); + + // A group with a server that is not in the live cluster + RSGroupInfo group = new RSGroupInfo("emptygroup"); + group.addServer(Address.fromParts("nonexistent.host", 9999)); + + Collection result = rm.filterRSGroupServers(group, allServers); + assertTrue(result.isEmpty()); + } + } +}