fix(server): ensure graph clear API does not clear meta table for hbase

hugegraph-server/hugegraph-hbase/src/main/java/org/apache/hugegraph/backend/store/hbase/HbaseStore.java

@@ -114,6 +114,14 @@ protected List<String> tableNames() {
                           .collect(Collectors.toList());
     }
 
+    protected List<String> getTableNamesExcludingMeta() {
+        // Exclude meta table to preserve system metadata during graph clear
+        return this.tables.entrySet().stream()
+                          .filter(e -> !(HugeType.META == e.getKey()))
+                          .map(e -> e.getValue().table())
+                          .collect(Collectors.toList());
+    }
+
     public String namespace() {
         return this.namespace;
     }
@@ -371,7 +379,7 @@ public void truncate() {
         };
 
         // Truncate tables
-        List<String> tables = this.tableNames();
+        List<String> tables = this.getTableNamesExcludingMeta();
         Map<String, Future<Void>> futures = new HashMap<>(tables.size());
 
         try {

hugegraph-server/hugegraph-test/src/main/java/org/apache/hugegraph/core/CoreTestSuite.java

@@ -24,6 +24,7 @@
 import org.apache.hugegraph.meta.MetaManager;
 import org.apache.hugegraph.meta.PdMetaDriver;
 import org.apache.hugegraph.testutil.Utils;
+import org.apache.hugegraph.unit.hbase.HbaseUnitTest;
 import org.apache.hugegraph.util.Log;
 import org.junit.AfterClass;
 import org.junit.Assert;
@@ -47,7 +48,9 @@
         TaskCoreTest.class,
         AuthTest.class,
         MultiGraphsTest.class,
-        RamTableTest.class
+        RamTableTest.class,
+        /* hbase */
+        HbaseUnitTest.class,
 })
 public class CoreTestSuite {
 

hugegraph-server/hugegraph-test/src/main/java/org/apache/hugegraph/unit/UnitTestSuite.java

@@ -44,6 +44,7 @@
 import org.apache.hugegraph.unit.core.SerialEnumTest;
 import org.apache.hugegraph.unit.core.SystemSchemaStoreTest;
 import org.apache.hugegraph.unit.core.TraversalUtilTest;
+import org.apache.hugegraph.unit.hbase.HbaseUnitTest;
 import org.apache.hugegraph.unit.id.EdgeIdTest;
 import org.apache.hugegraph.unit.id.IdTest;
 import org.apache.hugegraph.unit.id.IdUtilTest;
@@ -142,6 +143,7 @@
         RocksDBSessionTest.class,
         RocksDBCountersTest.class,
 
+
         /* utils */
         VersionTest.class,
         JsonUtilTest.class,

hugegraph-server/hugegraph-test/src/main/java/org/apache/hugegraph/unit/hbase/BaseHbaseUnitTest.java

@@ -0,0 +1,83 @@
+/*
+ * 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.hugegraph.unit.hbase;
+
+import org.apache.commons.configuration2.Configuration;
+import org.apache.hugegraph.backend.store.hbase.HbaseSessions;
+import org.apache.hugegraph.backend.store.hbase.HbaseStoreProvider;
+import org.apache.hugegraph.config.HugeConfig;
+import org.apache.hugegraph.testutil.Utils;
+import org.apache.hugegraph.unit.BaseUnitTest;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Assume;
+
+import java.io.IOException;
+
+public class BaseHbaseUnitTest extends BaseUnitTest {
+
+    private static final String GRAPH_NAME = "test_graph";
+
+    protected HugeConfig config;
+    protected HbaseStoreProvider provider;
+    protected HbaseSessions sessions;
+
+    @Before
+    public void setup() throws IOException {
+        Configuration conf = Utils.getConf();
+        String backend = conf.getString("backend", "memory");
+        // Only run HBase related tests when backend is hbase
+        Assume.assumeTrue("Skip HBase tests when backend is not hbase",
+                          "hbase".equalsIgnoreCase(backend));
+        this.config = new HugeConfig(conf);
+        this.provider = new HbaseStoreProvider();
+        try {
+            this.provider.open(GRAPH_NAME);
+            this.provider.loadSystemStore(config).open(config);
+            this.provider.loadGraphStore(config).open(config);
+            this.provider.loadSchemaStore(config).open(config);
+            this.provider.init();
+            this.sessions = new HbaseSessions(config, GRAPH_NAME, this.provider.loadGraphStore(config).store());
+            this.sessions.open();
+        } catch (Exception e) {
+            tearDown();
+            LOG.warn("Failed to init Hbasetest ", e);
+        }
+
+    }
+
+    @After
+    public void tearDown() {
+        if (this.sessions != null) {
+            try {
+                this.sessions.close();
+            } catch (Exception e) {
+                LOG.warn("Failed to close sessions ", e);
+            }
+        }
+        if (this.provider != null) {
+            // ensure back is clear
+            this.provider.truncate();
+            try {
+                this.provider.close();
+            } catch (Exception e) {
+                LOG.warn("Failed to close provider ", e);
+            }
+        }
+    }
+}

hugegraph-server/hugegraph-test/src/main/java/org/apache/hugegraph/unit/hbase/HbaseUnitTest.java

@@ -0,0 +1,89 @@
+/*
+ * 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.hugegraph.unit.hbase;
+
+import org.apache.hadoop.hbase.client.Result;
+import org.apache.hugegraph.backend.store.BackendEntry.BackendIterator;
+import org.apache.hugegraph.backend.store.BackendStore;
+import org.apache.hugegraph.testutil.Assert;
+import org.apache.hugegraph.backend.store.hbase.HbaseSessions;
+import org.apache.hugegraph.util.StringEncoding;
+import org.junit.Test;
+
+import java.nio.charset.StandardCharsets;
+
+public class HbaseUnitTest extends BaseHbaseUnitTest {
+
+    @Test
+    public void testHbaseMetaVersionAfterTruncate() {
+        BackendStore systemStore = this.provider.loadSystemStore(config);
+
+        // Record system version before truncation
+        String beforeVersion = systemStore.storedVersion();
+
+        HbaseSessions.Session testsession = this.sessions.session();
+
+        // Insert test data
+        testsession.put("g_v", "f".getBytes(StandardCharsets.UTF_8),
+                        "row_trunc_v".getBytes(StandardCharsets.UTF_8), StringEncoding.encode("q"),
+                        StringEncoding.encode("v"));
+        testsession.put("g_oe", "f".getBytes(StandardCharsets.UTF_8),
+                        "row_trunc_oe".getBytes(StandardCharsets.UTF_8),
+                        StringEncoding.encode("q"), StringEncoding.encode("v"));
+        testsession.put("g_ie", "f".getBytes(StandardCharsets.UTF_8),
+                        "row_trunc_ie".getBytes(StandardCharsets.UTF_8),
+                        StringEncoding.encode("q"), StringEncoding.encode("v"));
+        testsession.commit();
+
+        // Verify data insertion success
+        try (
+                BackendIterator<Result> vIterator = testsession.get("g_v", "f".getBytes(
+                        StandardCharsets.UTF_8), "row_trunc_v".getBytes(StandardCharsets.UTF_8));
+                BackendIterator<Result> oeIterator = testsession.get("g_oe", "f".getBytes(
+                        StandardCharsets.UTF_8), "row_trunc_oe".getBytes(StandardCharsets.UTF_8));
+                BackendIterator<Result> ieIterator = testsession.get("g_ie", "f".getBytes(
+                        StandardCharsets.UTF_8), "row_trunc_ie".getBytes(StandardCharsets.UTF_8));
+        ) {
+            Assert.assertTrue("data should exist", vIterator.hasNext());
+            Assert.assertTrue("data should exist", oeIterator.hasNext());
+            Assert.assertTrue("data should exist", ieIterator.hasNext());
+        }
+        // Execute truncate operation, clears all graph data but preserves system tables
+        this.provider.truncate();
+
+        // Verify system version remains unchanged after truncation
+        String afterVersion = systemStore.storedVersion();
+        Assert.assertNotNull("System metadata version should exist", afterVersion);
+        Assert.assertEquals("System metadata version should remain unchanged after truncation",
+                            beforeVersion, afterVersion);
+
+        // Verify data has been cleared
+        try (
+                BackendIterator<Result> vIterator = testsession.get("g_v", "f".getBytes(
+                        StandardCharsets.UTF_8), "row_trunc_v".getBytes(StandardCharsets.UTF_8));
+                BackendIterator<Result> oeIterator = testsession.get("g_oe", "f".getBytes(
+                        StandardCharsets.UTF_8), "row_trunc_oe".getBytes(StandardCharsets.UTF_8));
+                BackendIterator<Result> ieIterator = testsession.get("g_ie", "f".getBytes(
+                        StandardCharsets.UTF_8), "row_trunc_ie".getBytes(StandardCharsets.UTF_8));
+        ) {
+            Assert.assertFalse("data should not exist", vIterator.hasNext());
+            Assert.assertFalse("data should not exist", oeIterator.hasNext());
+            Assert.assertFalse("data should not exist", ieIterator.hasNext());
+        }
+    }
+}