Bugfix NPE that occurs during version upgrade with empty/default resource isolation group

fe/fe-core/src/main/java/com/starrocks/lake/LakeTablet.java

@@ -140,6 +140,9 @@ public void getQueryableReplicas(List<Replica> allQuerableReplicas, List<Replica
                                      long visibleVersion, long localBeId, int schemaHash, long warehouseId) {
         Set<Long> computeNodeIds = GlobalStateMgr.getCurrentState().getWarehouseMgr()
                 .getAllComputeNodeIdsAssignToTablet(warehouseId, this);
+        if (computeNodeIds == null) {
+            return;
+        }
         for (long backendId : computeNodeIds) {
             Replica replica = new Replica(getId(), backendId, visibleVersion, schemaHash, getDataSize(true),
                     getRowCount(visibleVersion), NORMAL, -1, visibleVersion);

fe/fe-core/src/main/java/com/starrocks/server/WarehouseManager.java

@@ -37,6 +37,7 @@
 import java.io.DataOutput;
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
@@ -207,8 +208,10 @@ public Set<Long> getAllComputeNodeIdsAssignToTablet(Long warehouseId, LakeTablet
                         " warehouse %d", warehouseId));
             }
             List<Long> computeNodeIds = systemInfoService.internalTabletMapper().computeNodesForTablet(tablet.getId());
-            if (computeNodeIds == null) {
-                return null;
+            if (computeNodeIds == null || computeNodeIds.isEmpty()) {
+                LOG.warn("no compute nodes assigned to tablet {} in warehouse {}", tablet.getId(),
+                        warehouseId);
+                return Collections.emptySet();
             }
             return new HashSet<>(computeNodeIds);
         }

fe/fe-core/src/main/java/com/starrocks/sql/analyzer/AlterSystemStmtAnalyzer.java

@@ -163,7 +163,8 @@ private void analyzeProperties(Map<String, String> properties, Set<String> suppo
                     continue;
                 }
                 // Support single level location label for now
-                String regex = "(\\s*[a-z_0-9]+\\s*:\\s*[a-z_0-9]+\\s*)";
+                // allow matching an empty val (after the colon)
+                String regex = "(\\s*[a-z_0-9]+\\s*:\\s*[a-z_0-9]*\\s*)";
                 if (!Pattern.compile(regex).matcher(propVal).matches()) {
                     throw new SemanticException("invalid 'location' or 'group' format: " + propVal +
                             ", should be like: 'key:val'");

fe/fe-core/src/main/java/com/starrocks/system/TabletComputeNodeMapper.java

@@ -37,6 +37,8 @@
 import com.starrocks.common.util.ConsistentHashRing;
 import com.starrocks.common.util.HashRing;
 import com.starrocks.server.GlobalStateMgr;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 import org.jetbrains.annotations.TestOnly;
 
 import java.util.Collections;
@@ -65,6 +67,7 @@
  */
 
 public class TabletComputeNodeMapper {
+    private static final Logger LOG = LogManager.getLogger(TabletComputeNodeMapper.class);
 
     private static final int CONSISTENT_HASH_RING_VIRTUAL_NUMBER = 256;
     private static final Long ARBITRARY_FAKE_TABLET = 1L;
@@ -169,9 +172,12 @@ public void modifyComputeNode(Long computeNodeId,
                                   String oldResourceIsolationGroup, String newResourceIsolationGroup) {
         oldResourceIsolationGroup = getResourceIsolationGroupName(oldResourceIsolationGroup);
         newResourceIsolationGroup = getResourceIsolationGroupName(newResourceIsolationGroup);
-        if (oldResourceIsolationGroup.equals(newResourceIsolationGroup)) {
-            return;
-        }
+        // We run the following even if oldResourceIsolationGroup.equals(newResourceIsolationGroup)
+        // because we want to cleanly handle edge cases where the compute node hasn't already been
+        // added to the TabletComputeNode mapper. This can happen in at least one situation, which
+        // is when the cluster is first upgraded to include resource isolation groups.
+        // Because the host ips match during a CN restart, upstream code which adds the ComputeNodes
+        // will not execute and therefore we won't call this.addComputeNode.
         writeLock.lock();
         try {
             removeComputeNodeUnsynchronized(computeNodeId, oldResourceIsolationGroup);
@@ -195,7 +201,9 @@ public List<Long> computeNodesForTablet(Long tabletId, int count, String resourc
         readLock.lock();
         try {
             if (!this.resourceIsolationGroupToTabletMapping.containsKey(resourceIsolationGroup)) {
-                return null;
+                LOG.warn(String.format("Requesting node for resource isolation group %s, to which"
+                        + " there is not a known CN assigned.", resourceIsolationGroup));
+                return Collections.emptyList();
             }
             TabletMap m = this.resourceIsolationGroupToTabletMapping.get(resourceIsolationGroup);
             return m.tabletToComputeNodeId.get(tabletId, count);

fe/fe-core/src/test/java/com/starrocks/server/WarehouseManagerTest.java

@@ -143,13 +143,13 @@ public NodeMgr getNodeMgr() {
             public SystemInfoService getClusterInfo() {
                 return systemInfo;
             }
+
             @Mock
             public Frontend getMySelf() {
                 return thisFe;
             }
         };
 
-
         TabletComputeNodeMapper tabletComputeNodeMapper = new TabletComputeNodeMapper();
         tabletComputeNodeMapper.addComputeNode(1L, thisFe.getResourceIsolationGroup());
         String otherResourceIsolationGroup = "someothergroup";
@@ -191,12 +191,12 @@ public TabletComputeNodeMapper internalTabletMapper() {
         mgr.initDefaultWarehouse();
 
         LakeTablet arbitraryTablet = new LakeTablet(1001L);
-        Assert.assertEquals(Set.of(1L), mgr.getAllComputeNodeIdsAssignToTablet(
-                WarehouseManager.DEFAULT_WAREHOUSE_ID, arbitraryTablet));
+        Assert.assertEquals(Set.of(1L),
+                mgr.getAllComputeNodeIdsAssignToTablet(WarehouseManager.DEFAULT_WAREHOUSE_ID, arbitraryTablet));
 
         thisFe.setResourceIsolationGroup(otherResourceIsolationGroup);
-        Assert.assertEquals(Set.of(2L), mgr.getAllComputeNodeIdsAssignToTablet(
-                WarehouseManager.DEFAULT_WAREHOUSE_ID, arbitraryTablet));
+        Assert.assertEquals(Set.of(2L),
+                mgr.getAllComputeNodeIdsAssignToTablet(WarehouseManager.DEFAULT_WAREHOUSE_ID, arbitraryTablet));
 
         // Check that WarehouseManager.getAllComputeNodeIdsAssignToTablet delegates to
         // systemInfo.getAvailableComputeNodeIds.
@@ -365,7 +365,10 @@ public RunMode getCurrentRunMode() {
         MaterializedIndex index = new MaterializedIndex(1, MaterializedIndex.IndexState.NORMAL);
         ErrorReportException ex = Assert.assertThrows(ErrorReportException.class,
                 () -> scanNode.addScanRangeLocations(partition, partition, index, Collections.emptyList(), 1));
-        Assert.assertEquals("No alive backend or compute node in warehouse null.", ex.getMessage());
+        Assert.assertEquals(
+                "No alive backend or compute node in warehouse null. Also possible that there are no CN of the resource " +
+                        "isolation group matching the FE.",
+                ex.getMessage());
     }
 
     private OlapScanNode newOlapScanNode() {

fe/fe-core/src/test/java/com/starrocks/system/TabletComputeNodeMapperTest.java

@@ -41,13 +41,15 @@
 import org.junit.Before;
 import org.junit.Test;
 
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
 public class TabletComputeNodeMapperTest {
     private Frontend thisFe;
+
     @Before
     public void setUp() {
         thisFe = new Frontend();
@@ -66,6 +68,17 @@ public void setUp() {
     public void tearDown() {
     }
 
+    @Test
+    public void modifyComputeNodeEdgeCases() throws Exception {
+        Long arbitraryTablet = 9000L;
+        TabletComputeNodeMapper mapper = new TabletComputeNodeMapper();
+        Assert.assertEquals(0, mapper.numResourceIsolationGroups());
+        Assert.assertEquals(Collections.emptyList(), mapper.computeNodesForTablet(arbitraryTablet, 1, ""));
+        mapper.modifyComputeNode(1L, "", "");
+        Assert.assertEquals(1, mapper.numResourceIsolationGroups());
+        Assert.assertEquals(List.of(1L), mapper.computeNodesForTablet(arbitraryTablet, 1, ""));
+    }
+
     @Test
     public void testGroupManagementEdgeCase() throws Exception {
         TabletComputeNodeMapper mapper = new TabletComputeNodeMapper();
@@ -75,7 +88,6 @@ public void testGroupManagementEdgeCase() throws Exception {
         Assert.assertTrue(mapper.trackingNonDefaultResourceIsolationGroup());
     }
 
-
     @Test
     public void testGroupManagement() throws Exception {
         TabletComputeNodeMapper mapper = new TabletComputeNodeMapper();
@@ -143,7 +155,6 @@ public void testTabletToCnMapping() throws Exception {
 
         Assert.assertEquals(2, mapper.numResourceIsolationGroups());
 
-
         int tabletsToTry = 10000;
         long[] tabletIdToGroup2Primary = new long[tabletsToTry];
         long[] tabletIdToGroup2Backup = new long[tabletsToTry];