[#2401] improvement(spark-connector): support alter namespace operati…

…on (#2407)

### What changes were proposed in this pull request?

Support alter namespace operation implementation.

### Why are the changes needed?

Support to set namespace properties in Spark sql like:

```
ALTER DATABASE inventory SET DBPROPERTIES ('Edited-by' = 'John', 'Edit-date' = '01/01/2001');
```

Fix: #2401

### Does this PR introduce _any_ user-facing change?

No.

### How was this patch tested?

- `SparkIT#testAlterSchema`

integration-test/src/test/java/com/datastrato/gravitino/integration/test/spark/SparkIT.java

@@ -42,21 +42,39 @@ void testCreateAndLoadSchema() {
     Assertions.assertTrue(StringUtils.isBlank(properties));
 
     testDatabaseName = "t_create2";
+    String testDatabaseLocation = "/tmp/" + testDatabaseName;
     sql(
         String.format(
-            "CREATE DATABASE %s COMMENT 'comment' LOCATION '/user'\n"
-                + " WITH DBPROPERTIES (ID=001);",
-            testDatabaseName));
+            "CREATE DATABASE %s COMMENT 'comment' LOCATION '%s'\n" + " WITH DBPROPERTIES (ID=001);",
+            testDatabaseName, testDatabaseLocation));
     databaseMeta = getDatabaseMetadata(testDatabaseName);
     String comment = databaseMeta.get("Comment");
     Assertions.assertEquals("comment", comment);
     Assertions.assertEquals("datastrato", databaseMeta.get("Owner"));
-    // underlying catalog may change /user to file:/user
-    Assertions.assertTrue(databaseMeta.get("Location").contains("/user"));
+    // underlying catalog may change /tmp/t_create2 to file:/tmp/t_create2
+    Assertions.assertTrue(databaseMeta.get("Location").contains(testDatabaseLocation));
     properties = databaseMeta.get("Properties");
     Assertions.assertEquals("((ID,001))", properties);
   }
 
+  @Test
+  void testAlterSchema() {
+    String testDatabaseName = "t_alter";
+    sql("CREATE DATABASE " + testDatabaseName);
+    Assertions.assertTrue(
+        StringUtils.isBlank(getDatabaseMetadata(testDatabaseName).get("Properties")));
+
+    sql(String.format("ALTER DATABASE %s SET DBPROPERTIES ('ID'='001')", testDatabaseName));
+    Assertions.assertEquals("((ID,001))", getDatabaseMetadata(testDatabaseName).get("Properties"));
+
+    // Hive metastore doesn't support alter database location, therefore this test method
+    // doesn't verify ALTER DATABASE database_name SET LOCATION 'new_location'.
+
+    Assertions.assertThrowsExactly(
+        NoSuchNamespaceException.class,
+        () -> sql("ALTER DATABASE notExists SET DBPROPERTIES ('ID'='001')"));
+  }
+
   @Test
   void testDropSchema() {
     String testDatabaseName = "t_drop";

spark-connector/src/main/java/com/datastrato/gravitino/spark/catalog/GravitinoCatalog.java

@@ -12,6 +12,7 @@
 import com.datastrato.gravitino.exceptions.NonEmptySchemaException;
 import com.datastrato.gravitino.exceptions.SchemaAlreadyExistsException;
 import com.datastrato.gravitino.rel.Schema;
+import com.datastrato.gravitino.rel.SchemaChange;
 import com.datastrato.gravitino.spark.GravitinoSparkConfig;
 import com.google.common.base.Preconditions;
 import java.util.Arrays;
@@ -30,6 +31,7 @@
 import org.apache.spark.sql.connector.catalog.Column;
 import org.apache.spark.sql.connector.catalog.Identifier;
 import org.apache.spark.sql.connector.catalog.NamespaceChange;
+import org.apache.spark.sql.connector.catalog.NamespaceChange.SetProperty;
 import org.apache.spark.sql.connector.catalog.SupportsNamespaces;
 import org.apache.spark.sql.connector.catalog.Table;
 import org.apache.spark.sql.connector.catalog.TableCatalog;
@@ -175,7 +177,28 @@ public void createNamespace(String[] namespace, Map<String, String> metadata)
   @Override
   public void alterNamespace(String[] namespace, NamespaceChange... changes)
       throws NoSuchNamespaceException {
-    throw new NotSupportedException("Doesn't support altering namespace");
+    validateNamespace(namespace);
+    SchemaChange[] schemaChanges =
+        Arrays.stream(changes)
+            .map(
+                change -> {
+                  if (change instanceof SetProperty) {
+                    SetProperty setProperty = ((SetProperty) change);
+                    return SchemaChange.setProperty(setProperty.property(), setProperty.value());
+                  } else {
+                    throw new UnsupportedOperationException(
+                        String.format(
+                            "Unsupported namespace change %s", change.getClass().getName()));
+                  }
+                })
+            .toArray(SchemaChange[]::new);
+    try {
+      gravitinoCatalogClient
+          .asSchemas()
+          .alterSchema(NameIdentifier.of(metalakeName, catalogName, namespace[0]), schemaChanges);
+    } catch (NoSuchSchemaException e) {
+      throw new NoSuchNamespaceException(namespace);
+    }
   }
 
   @Override