HBASE-30411 Support regex based RS membership assignment to RS group

hbase-server/src/main/java/org/apache/hadoop/hbase/rsgroup/RSGroupBasedLoadBalancer.java

@@ -17,6 +17,7 @@
  */
 package org.apache.hadoop.hbase.rsgroup;
 
+import com.google.errorprone.annotations.RestrictedApi;
 import edu.umd.cs.findbugs.annotations.NonNull;
 import java.io.IOException;
 import java.util.ArrayList;
@@ -99,6 +100,44 @@ public class RSGroupBasedLoadBalancer implements LoadBalancer {
 
   private volatile boolean fallbackEnabled = false;
 
+  @RestrictedApi(explanation = "Should only be called in tests", link = "",
+      allowedOnPath = ".*/src/test/.*")
+  public void setFallbackEnabledForTest(boolean enabled) {
+    this.fallbackEnabled = enabled;
+  }
+
+  // Test-only call-tracking flags, set true whenever the corresponding assignment method below is
+  // invoked. Reset via resetAssignmentCallFlagsForTest() before the operation under test.
+  private volatile boolean roundRobinAssignmentInvoked = false;
+  private volatile boolean retainAssignmentInvoked = false;
+  private volatile boolean randomAssignmentInvoked = false;
+
+  @RestrictedApi(explanation = "Should only be called in tests", link = "",
+      allowedOnPath = ".*/src/test/.*")
+  public boolean isRoundRobinAssignmentInvoked() {
+    return roundRobinAssignmentInvoked;
+  }
+
+  @RestrictedApi(explanation = "Should only be called in tests", link = "",
+      allowedOnPath = ".*/src/test/.*")
+  public boolean isRetainAssignmentInvoked() {
+    return retainAssignmentInvoked;
+  }
+
+  @RestrictedApi(explanation = "Should only be called in tests", link = "",
+      allowedOnPath = ".*/src/test/.*")
+  public boolean isRandomAssignmentInvoked() {
+    return randomAssignmentInvoked;
+  }
+
+  @RestrictedApi(explanation = "Should only be called in tests", link = "",
+      allowedOnPath = ".*/src/test/.*")
+  public void resetAssignmentCallFlagsForTest() {
+    roundRobinAssignmentInvoked = false;
+    retainAssignmentInvoked = false;
+    randomAssignmentInvoked = false;
+  }
+
   /**
    * Used by reflection in {@link org.apache.hadoop.hbase.master.balancer.LoadBalancerFactory}.
    */
@@ -180,6 +219,7 @@ public synchronized List<RegionPlan> balanceCluster(
   @NonNull
   public Map<ServerName, List<RegionInfo>> roundRobinAssignment(List<RegionInfo> regions,
     List<ServerName> servers) throws IOException {
+    roundRobinAssignmentInvoked = true;
     Map<ServerName, List<RegionInfo>> assignments = Maps.newHashMap();
     List<Pair<List<RegionInfo>, List<ServerName>>> pairs =
       generateGroupAssignments(regions, servers);
@@ -196,6 +236,7 @@ public Map<ServerName, List<RegionInfo>> roundRobinAssignment(List<RegionInfo> r
   @NonNull
   public Map<ServerName, List<RegionInfo>> retainAssignment(Map<RegionInfo, ServerName> regions,
     List<ServerName> servers) throws HBaseIOException {
+    retainAssignmentInvoked = true;
     try {
       Map<ServerName, List<RegionInfo>> assignments = new TreeMap<>();
       List<Pair<List<RegionInfo>, List<ServerName>>> pairs =
@@ -218,6 +259,7 @@ public Map<ServerName, List<RegionInfo>> retainAssignment(Map<RegionInfo, Server
   @Override
   public ServerName randomAssignment(RegionInfo region, List<ServerName> servers)
     throws IOException {
+    randomAssignmentInvoked = true;
     List<Pair<List<RegionInfo>, List<ServerName>>> pairs =
       generateGroupAssignments(Lists.newArrayList(region), servers);
     List<ServerName> filteredServers = pairs.iterator().next().getSecond();

hbase-server/src/test/java/org/apache/hadoop/hbase/rsgroup/TestRSGroupsBase.java

@@ -17,6 +17,8 @@
  */
 package org.apache.hadoop.hbase.rsgroup;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import java.io.IOException;
@@ -207,6 +209,11 @@ protected final RSGroupInfo addGroup(String groupName, int serverCount)
     }
     ADMIN.moveServersToRSGroup(set, groupName);
     RSGroupInfo result = ADMIN.getRSGroup(groupName);
+    assertEquals(set, result.getServers());
+    Set<Address> remainingDefaultServers = ADMIN.getRSGroup(RSGroupInfo.DEFAULT_GROUP).getServers();
+    for (Address server : set) {
+      assertFalse(remainingDefaultServers.contains(server));
+    }
     return result;
   }
 
@@ -226,8 +233,29 @@ protected final void removeGroup(String groupName) throws IOException {
       }
     }
     RSGroupInfo groupInfo = ADMIN.getRSGroup(groupName);
-    ADMIN.moveServersToRSGroup(groupInfo.getServers(), RSGroupInfo.DEFAULT_GROUP);
+    Set<Address> servers = groupInfo.getServers();
+    ADMIN.moveServersToRSGroup(servers, RSGroupInfo.DEFAULT_GROUP);
     ADMIN.removeRSGroup(groupName);
+    assertFalse(ADMIN.listRSGroups().stream().anyMatch(g -> g.getName().equals(groupName)));
+    Set<Address> onlineServers = new HashSet<>();
+    for (ServerName sn : MASTER.getServerManager().getOnlineServersList()) {
+      onlineServers.add(sn.getAddress());
+    }
+    RSGroupInfo defaultInfo = ADMIN.getRSGroup(RSGroupInfo.DEFAULT_GROUP);
+    for (Address server : servers) {
+      // moveServersToRSGroup()-to-'default' silently drops servers that are no longer online
+      // (see RSGroupInfoManagerImpl#moveServers), so only online servers are guaranteed to land
+      // in 'default'; an offline server's former group membership is simply dropped.
+      if (onlineServers.contains(server)) {
+        assertTrue(defaultInfo.getServers().contains(server));
+      }
+    }
+    for (TableName table : tables) {
+      // ADMIN.getRSGroup(String)/listRSGroups() do not resolve table membership from the
+      // TableDescriptor's RegionServerGroup attribute (only ADMIN.getRSGroup(TableName) does),
+      // so look up each table's group individually rather than via defaultInfo.getTables().
+      assertEquals(RSGroupInfo.DEFAULT_GROUP, ADMIN.getRSGroup(table).getName());
+    }
   }
 
   protected final void deleteTableIfNecessary() throws IOException {