Implement batching statements in Hibernate UPDATE mode

google-cloud-spanner-hibernate-dialect/src/main/java/com/google/cloud/spanner/hibernate/SpannerServiceContributor.java

@@ -22,6 +22,7 @@
 import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
 import org.hibernate.hql.spi.id.inline.InlineIdsOrClauseBulkIdStrategy;
 import org.hibernate.service.spi.ServiceContributor;
+import org.hibernate.tool.hbm2ddl.UniqueConstraintSchemaUpdateStrategy;
 
 /**
  * An implementation of a Hibernate {@link ServiceContributor} which provides custom settings
@@ -46,6 +47,10 @@ public void contribute(StandardServiceRegistryBuilder serviceRegistryBuilder) {
         .applySetting("hibernate.connection.userAgent", HIBERNATE_API_CLIENT_LIB_TOKEN)
         // The custom Hibernate schema management tool for Spanner.
         .applySetting("hibernate.schema_management_tool", SCHEMA_MANAGEMENT_TOOL)
+        // Create a unique index for a table if it does not already exist when in UPDATE mode.
+        .applySetting(
+            "hibernate.schema_update.unique_constraint_strategy",
+            UniqueConstraintSchemaUpdateStrategy.RECREATE_QUIETLY)
         // Allows entities to be used with InheritanceType.JOINED in Spanner.
         .applySetting("hibernate.hql.bulk_id_strategy", InlineIdsOrClauseBulkIdStrategy.INSTANCE);
   }

google-cloud-spanner-hibernate-dialect/src/main/java/com/google/cloud/spanner/hibernate/schema/RunBatchDdl.java

@@ -21,13 +21,20 @@
 import com.google.cloud.spanner.hibernate.SpannerDialect;
 import org.hibernate.boot.model.relational.AuxiliaryDatabaseObject;
 import org.hibernate.dialect.Dialect;
+import org.hibernate.tool.schema.Action;
 
 /**
  * Custom {@link AuxiliaryDatabaseObject} which generates the RUN BATCH statement.
  */
 public class RunBatchDdl implements AuxiliaryDatabaseObject {
   private static final long serialVersionUID = 1L;
 
+  private final Action schemaAction;
+
+  public RunBatchDdl(Action schemaAction) {
+    this.schemaAction = schemaAction;
+  }
+
   @Override
   public String getExportIdentifier() {
     return "RUN_BATCH_DDL";
@@ -40,7 +47,7 @@ public boolean appliesToDialect(Dialect dialect) {
 
   @Override
   public boolean beforeTablesOnCreation() {
-    return false;
+    return schemaAction == Action.UPDATE;
   }
 
   @Override
@@ -50,6 +57,10 @@ public String[] sqlCreateStrings(Dialect dialect) {
 
   @Override
   public String[] sqlDropStrings(Dialect dialect) {
-    return new String[] {"RUN BATCH"};
+    if (schemaAction == Action.UPDATE) {
+      return new String[]{};
+    } else {
+      return new String[]{"RUN BATCH"};
+    }
   }
 }

google-cloud-spanner-hibernate-dialect/src/main/java/com/google/cloud/spanner/hibernate/schema/SpannerSchemaCreator.java

@@ -48,8 +48,8 @@ public void doCreation(
       TargetDescriptor targetDescriptor) {
 
     // Add auxiliary database objects to batch DDL statements
-    metadata.getDatabase().addAuxiliaryDatabaseObject(new StartBatchDdl());
-    metadata.getDatabase().addAuxiliaryDatabaseObject(new RunBatchDdl());
+    metadata.getDatabase().addAuxiliaryDatabaseObject(new StartBatchDdl(Action.CREATE));
+    metadata.getDatabase().addAuxiliaryDatabaseObject(new RunBatchDdl(Action.CREATE));
 
     // Initialize exporters with interleave dependencies so tables are created in the right order.
     tool.getSpannerTableExporter(options).initializeTableExporter(metadata, Action.CREATE);

google-cloud-spanner-hibernate-dialect/src/main/java/com/google/cloud/spanner/hibernate/schema/SpannerSchemaDropper.java

@@ -49,8 +49,8 @@ public void doDrop(
       TargetDescriptor targetDescriptor) {
 
     // Initialize auxiliary database objects to enable DDL statement batching.
-    metadata.getDatabase().addAuxiliaryDatabaseObject(new StartBatchDdl());
-    metadata.getDatabase().addAuxiliaryDatabaseObject(new RunBatchDdl());
+    metadata.getDatabase().addAuxiliaryDatabaseObject(new StartBatchDdl(Action.DROP));
+    metadata.getDatabase().addAuxiliaryDatabaseObject(new RunBatchDdl(Action.DROP));
 
     // Initialize exporters with drop table dependencies so tables are dropped in the right order.
     tool.getSpannerTableExporter(options).initializeTableExporter(metadata, Action.DROP);

google-cloud-spanner-hibernate-dialect/src/main/java/com/google/cloud/spanner/hibernate/schema/SpannerSchemaMigrator.java

@@ -44,7 +44,11 @@ public SpannerSchemaMigrator(SpannerSchemaManagementTool tool, SchemaMigrator sc
   public void doMigration(
       Metadata metadata, ExecutionOptions options, TargetDescriptor targetDescriptor) {
 
-    tool.getSpannerTableExporter(options).initializeTableExporter(metadata, Action.CREATE);
+    // Add auxiliary database objects to batch DDL statements
+    metadata.getDatabase().addAuxiliaryDatabaseObject(new StartBatchDdl(Action.UPDATE));
+    metadata.getDatabase().addAuxiliaryDatabaseObject(new RunBatchDdl(Action.UPDATE));
+
+    tool.getSpannerTableExporter(options).initializeTableExporter(metadata, Action.UPDATE);
 
     schemaMigrator.doMigration(metadata, options, targetDescriptor);
   }

google-cloud-spanner-hibernate-dialect/src/main/java/com/google/cloud/spanner/hibernate/schema/StartBatchDdl.java

@@ -21,13 +21,20 @@
 import com.google.cloud.spanner.hibernate.SpannerDialect;
 import org.hibernate.boot.model.relational.AuxiliaryDatabaseObject;
 import org.hibernate.dialect.Dialect;
+import org.hibernate.tool.schema.Action;
 
 /**
  * Custom {@link AuxiliaryDatabaseObject} which generates the START BATCH DDL statement.
  */
 public class StartBatchDdl implements AuxiliaryDatabaseObject {
   private static final long serialVersionUID = 1L;
 
+  private final Action schemaAction;
+
+  public StartBatchDdl(Action schemaAction) {
+    this.schemaAction = schemaAction;
+  }
+
   @Override
   public String getExportIdentifier() {
     return "START_BATCH_DDL";
@@ -40,7 +47,7 @@ public boolean appliesToDialect(Dialect dialect) {
 
   @Override
   public boolean beforeTablesOnCreation() {
-    return true;
+    return schemaAction != Action.UPDATE;
   }
 
   @Override
@@ -50,6 +57,10 @@ public String[] sqlCreateStrings(Dialect dialect) {
 
   @Override
   public String[] sqlDropStrings(Dialect dialect) {
-    return new String[] {"START BATCH DDL"};
+    if (schemaAction == Action.UPDATE) {
+      return new String[]{};
+    } else {
+      return new String[]{"START BATCH DDL"};
+    }
   }
 }

google-cloud-spanner-hibernate-dialect/src/main/java/com/google/cloud/spanner/hibernate/schema/TableDependencyTracker.java

@@ -56,7 +56,7 @@ public void initializeDependencies(Metadata metadata, Action schemaAction) {
     for (Table childTable : metadata.collectTableMappings()) {
       Interleaved interleaved = SchemaUtils.getInterleaveAnnotation(childTable, metadata);
       if (interleaved != null) {
-        if (schemaAction == Action.CREATE) {
+        if (schemaAction == Action.CREATE || schemaAction == Action.UPDATE) {
           // If creating tables, the parent blocks the child.
           dependencies.put(childTable, SchemaUtils.getTable(interleaved.parentEntity(), metadata));
         } else {

google-cloud-spanner-hibernate-dialect/src/test/java/com/google/cloud/spanner/hibernate/GeneratedUpdateTableStatementsTests.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2019 Google LLC
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+package com.google.cloud.spanner.hibernate;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.google.cloud.spanner.hibernate.entities.Employee;
+import com.mockrunner.mock.jdbc.JDBCMockObjectFactory;
+import com.mockrunner.mock.jdbc.MockConnection;
+import java.sql.SQLException;
+import java.util.List;
+import org.hibernate.Session;
+import org.hibernate.boot.Metadata;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.boot.registry.StandardServiceRegistry;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.junit.Before;
+import org.junit.Test;
+
+public class GeneratedUpdateTableStatementsTests {
+
+  private StandardServiceRegistry registry;
+
+  private JDBCMockObjectFactory jdbcMockObjectFactory;
+
+  private MockConnection mockConnection;
+
+  /**
+   * Set up the metadata for Hibernate to generate schema statements.
+   */
+  @Before
+  public void setup() {
+    this.jdbcMockObjectFactory = new JDBCMockObjectFactory();
+    this.jdbcMockObjectFactory.registerMockDriver();
+
+    mockConnection = this.jdbcMockObjectFactory.createMockConnection();
+
+    this.jdbcMockObjectFactory
+        .getMockDriver()
+        .setupConnection(mockConnection);
+
+    this.registry = new StandardServiceRegistryBuilder()
+        .applySetting("hibernate.dialect", SpannerDialect.class.getName())
+        // must NOT set a driver class name so that Hibernate will use java.sql.DriverManager
+        // and discover the only mock driver we have set up.
+        .applySetting("hibernate.connection.url", "unused")
+        .applySetting("hibernate.connection.username", "unused")
+        .applySetting("hibernate.connection.password", "unused")
+        .applySetting("hibernate.hbm2ddl.auto", "update")
+        .build();
+  }
+
+  @Test
+  public void testUpdateStatements_createTables() throws SQLException {
+    setupTestTables("Hello");
+
+    List<String> sqlStrings = mockConnection.getStatementResultSetHandler().getExecutedStatements();
+    assertThat(sqlStrings).containsExactly(
+        "START BATCH DDL",
+        "create table Employee (id INT64 not null,name STRING(255),manager_id INT64) "
+            + "PRIMARY KEY (id)",
+        "create table hibernate_sequence (next_val INT64) PRIMARY KEY ()",
+        "INSERT INTO hibernate_sequence (next_val) VALUES(1)",
+        "create index name_index on Employee (name)",
+        "RUN BATCH"
+    );
+  }
+
+  @Test
+  public void testUpdateStatements_alterTables() throws SQLException {
+    setupTestTables("Employee");
+
+    List<String> sqlStrings = mockConnection.getStatementResultSetHandler().getExecutedStatements();
+    assertThat(sqlStrings).containsExactly(
+        "START BATCH DDL",
+        "alter table Employee ADD COLUMN id INT64 not null",
+        "alter table Employee ADD COLUMN name STRING(255)",
+        "alter table Employee ADD COLUMN manager_id INT64",
+        "create table hibernate_sequence (next_val INT64) PRIMARY KEY ()",
+        "INSERT INTO hibernate_sequence (next_val) VALUES(1)",
+        "create index name_index on Employee (name)",
+        "RUN BATCH"
+    );
+  }
+
+  /**
+   * Sets up which pre-existing tables that Hibernate sees.
+   */
+  private void setupTestTables(String... tables) throws SQLException {
+    mockConnection.setMetaData(MockJdbcUtils.createMockDatabaseMetaData(tables));
+
+    Metadata metadata =
+        new MetadataSources(this.registry)
+            .addAnnotatedClass(Employee.class)
+            .buildMetadata();
+
+    Session session = metadata.buildSessionFactory().openSession();
+    session.beginTransaction();
+    session.close();
+  }
+}

google-cloud-spanner-hibernate-dialect/src/test/java/com/google/cloud/spanner/hibernate/MockJdbcUtils.java

@@ -0,0 +1,103 @@
+/*
+ * Copyright 2019 Google LLC
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+package com.google.cloud.spanner.hibernate;
+
+import com.mockrunner.mock.jdbc.MockDatabaseMetaData;
+import com.mockrunner.mock.jdbc.MockResultSet;
+import java.sql.ResultSet;
+import java.sql.Types;
+import java.util.Arrays;
+import java.util.UUID;
+
+/**
+ * Helper class to building mock objects for the mock JDBC driver.
+ */
+public class MockJdbcUtils {
+
+  private static final String[] TABLE_METADATA_COLUMNS = new String[]{
+      "TABLE_CAT", "TABLE_SCHEM", "TABLE_NAME", "TABLE_TYPE", "REMARKS", "TYPE_CAT",
+      "TYPE_SCHEM", "TYPE_NAME", "SELF_REFERENCING_COL_NAME", "REF"
+  };
+
+  private static final String[] COLUMN_METADATA_LABELS = new String[]{
+      "TABLE_CAT", "TABLE_SCHEM", "TABLE_NAME", "COLUMN_NAME", "DATA_TYPE",
+      "TYPE_NAME", "COLUMN_SIZE", "DECIMAL_DIGITS", "IS_NULLABLE",
+  };
+
+  /**
+   * Creates the metadata object read by Hibernate to determine which tables already exist.
+   */
+  public static MockDatabaseMetaData createMockDatabaseMetaData(String... tables) {
+    MockDatabaseMetaData mockDatabaseMetaData = new MockDatabaseMetaData();
+    mockDatabaseMetaData.setColumns(createColumnMetadataResultSet(tables));
+    mockDatabaseMetaData.setTables(createTableMetadataResultSet(tables));
+    mockDatabaseMetaData.setIndexInfo(new MockResultSet(UUID.randomUUID().toString()));
+    mockDatabaseMetaData.setImportedKeys(new MockResultSet(UUID.randomUUID().toString()));
+    return mockDatabaseMetaData;
+  }
+
+  /**
+   * Constructs a mock Column metadata {@link ResultSet} describing fake columns of the tables.
+   */
+  private static ResultSet createColumnMetadataResultSet(String... tableNames) {
+    MockResultSet mockResultSet = initResultSet(COLUMN_METADATA_LABELS);
+
+    for (int i = 0; i < tableNames.length; i++) {
+      Object[] row = new Object[COLUMN_METADATA_LABELS.length];
+      Arrays.fill(row, "");
+      row[2] = tableNames[i];
+      row[3] = "column";
+      row[4] = Types.VARCHAR;
+      row[5] = "string(255)";
+      row[6] = 255;
+      row[7] = 0;
+      row[8] = 0;
+      mockResultSet.addRow(row);
+    }
+
+    return mockResultSet;
+  }
+
+
+  /**
+   * Constructs a mock Table metadata {@link ResultSet} describing table names.
+   */
+  private static ResultSet createTableMetadataResultSet(String... tableNames) {
+    MockResultSet mockResultSet = initResultSet(TABLE_METADATA_COLUMNS);
+
+    for (int i = 0; i < tableNames.length; i++) {
+      String[] row = new String[TABLE_METADATA_COLUMNS.length];
+      Arrays.fill(row, "");
+      row[2] = tableNames[i];
+      row[3] = "TABLE";
+      mockResultSet.addRow(row);
+    }
+
+    return mockResultSet;
+  }
+
+  private static MockResultSet initResultSet(String[] columnLabels) {
+    MockResultSet mockResultSet = new MockResultSet(UUID.randomUUID().toString());
+    for (int i = 0; i < columnLabels.length; i++) {
+      mockResultSet.addColumn(columnLabels[i]);
+    }
+
+    return mockResultSet;
+  }
+}

pom.xml

@@ -13,7 +13,7 @@
     <maven.compiler.source>1.8</maven.compiler.source>
     <maven.compiler.target>1.8</maven.compiler.target>
     <hibernate.version>5.4.9.Final</hibernate.version>
-    <spanner-jdbc-driver.version>1.11.0</spanner-jdbc-driver.version>
+    <spanner-jdbc-driver.version>1.12.0</spanner-jdbc-driver.version>
     <log4j.version>1.2.17</log4j.version>
     <google-cloud-spanner.version>1.43.0</google-cloud-spanner.version>
   </properties>