Autodetect spring.jpa.database from spring.datasource.url

Previously, property `spring.jpa.database` should be provided. This
commit allows to detect the database when `spring.datasource.url` is
provided.

Closes gh-7708

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/orm/jpa/DatabasePlatform.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright 2012-2016 the original author or authors.
+ *
+ * Licensed 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.springframework.boot.autoconfigure.orm.jpa;
+
+import org.springframework.boot.jdbc.DatabaseDriver;
+import org.springframework.orm.jpa.vendor.Database;
+
+/**
+ * Mapper between {@link Database} and {@link DatabaseDriver}.
+ *
+ * @author Eddú Meléndez
+ * @version 1.5.0
+ */
+public enum DatabasePlatform {
+
+	DB2(Database.DB2, DatabaseDriver.DB2),
+
+	DERBY(Database.DERBY, DatabaseDriver.DERBY),
+
+	H2(Database.H2, DatabaseDriver.H2),
+
+	HSQL(Database.HSQL, DatabaseDriver.HSQLDB),
+
+	INFORMIX(Database.INFORMIX, DatabaseDriver.INFORMIX),
+
+	MYSQL(Database.MYSQL, DatabaseDriver.MYSQL),
+
+	ORACLE(Database.ORACLE, DatabaseDriver.ORACLE),
+
+	POSTGRESQL(Database.POSTGRESQL, DatabaseDriver.POSTGRESQL),
+
+	SQL_SERVER(Database.SQL_SERVER, DatabaseDriver.SQLSERVER);
+
+	private final Database database;
+
+	private final DatabaseDriver driver;
+
+	DatabasePlatform(Database database, DatabaseDriver driver) {
+		this.database = database;
+		this.driver = driver;
+	}
+
+	public Database getDatabase() {
+		return this.database;
+	}
+
+	public DatabaseDriver getDriver() {
+		return this.driver;
+	}
+
+	public static DatabasePlatform fromDatabaseDriver(DatabaseDriver driver) {
+		for (DatabasePlatform mapper : values()) {
+			if (mapper.getDriver() == driver) {
+				return mapper;
+			}
+		}
+		return null;
+	}
+
+}

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/orm/jpa/JpaBaseConfiguration.java

@@ -41,6 +41,8 @@ import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
 import org.springframework.context.annotation.Primary;
+import org.springframework.jdbc.support.JdbcUtils;
+import org.springframework.jdbc.support.MetaDataAccessException;
 import org.springframework.orm.jpa.JpaTransactionManager;
 import org.springframework.orm.jpa.JpaVendorAdapter;
 import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
@@ -61,6 +63,7 @@ import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter
  * @author Oliver Gierke
  * @author Andy Wilkinson
  * @author Kazuki Shimizu
+ * @author Eddú Meléndez
  */
 @EnableConfigurationProperties(JpaProperties.class)
 @Import(DataSourceInitializedPublisher.Registrar.class)
@@ -101,7 +104,14 @@ public abstract class JpaBaseConfiguration implements BeanFactoryAware {
 	public JpaVendorAdapter jpaVendorAdapter() {
 		AbstractJpaVendorAdapter adapter = createJpaVendorAdapter();
 		adapter.setShowSql(this.properties.isShowSql());
-		adapter.setDatabase(this.properties.getDatabase());
+		try {
+			String jdbcUrl = (String) JdbcUtils.extractDatabaseMetaData(this.dataSource,
+					"getURL");
+			adapter.setDatabase(this.properties.determineDatabase(jdbcUrl));
+		}
+		catch (MetaDataAccessException ex) {
+			throw new IllegalStateException("Unable to detect database type", ex);
+		}
 		adapter.setDatabasePlatform(this.properties.getDatabasePlatform());
 		adapter.setGenerateDdl(this.properties.isGenerateDdl());
 		return adapter;

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/orm/jpa/JpaProperties.java

@@ -24,6 +24,7 @@ import javax.sql.DataSource;
 import org.springframework.boot.autoconfigure.jdbc.EmbeddedDatabaseConnection;
 import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.boot.context.properties.NestedConfigurationProperty;
+import org.springframework.boot.jdbc.DatabaseDriver;
 import org.springframework.orm.jpa.vendor.Database;
 import org.springframework.util.StringUtils;
 
@@ -33,6 +34,7 @@ import org.springframework.util.StringUtils;
  * @author Dave Syer
  * @author Andy Wilkinson
  * @author Stephane Nicoll
+ * @author Eddú Meléndez
  * @since 1.1.0
  */
 @ConfigurationProperties(prefix = "spring.jpa")
@@ -125,6 +127,20 @@ public class JpaProperties {
 		return this.hibernate.getAdditionalProperties(this.properties, dataSource);
 	}
 
+	/**
+	 * Return the database form the jdbc url or the value for `spring.jpa.database`.
+	 * @param jdbcUrl the url from `spring.datasource.url`
+	 * @return {@code Database}
+	 */
+	public Database determineDatabase(String jdbcUrl) {
+		DatabasePlatform databasePlatform = DatabasePlatform.fromDatabaseDriver(
+				DatabaseDriver.fromJdbcUrl(jdbcUrl));
+		if (databasePlatform != null) {
+			return databasePlatform.getDatabase();
+		}
+		return this.database;
+	}
+
 	public static class Hibernate {
 
 		private static final String USE_NEW_ID_GENERATOR_MAPPINGS = "hibernate.id."

spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/orm/jpa/CustomHibernateJpaAutoConfigurationTests.java

@@ -16,6 +16,9 @@
 
 package org.springframework.boot.autoconfigure.orm.jpa;
 
+import java.sql.Connection;
+import java.sql.DatabaseMetaData;
+import java.sql.SQLException;
 import java.util.Map;
 
 import javax.sql.DataSource;
@@ -30,15 +33,22 @@ import org.springframework.boot.autoconfigure.jdbc.EmbeddedDataSourceConfigurati
 import org.springframework.boot.autoconfigure.orm.jpa.test.City;
 import org.springframework.boot.test.util.EnvironmentTestUtils;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.orm.jpa.vendor.Database;
+import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
+import org.springframework.test.util.ReflectionTestUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.BDDMockito.mock;
 
 /**
  * Tests for {@link HibernateJpaAutoConfiguration}.
  *
  * @author Dave Syer
  * @author Phillip Webb
+ * @author Eddú Meléndez
  */
 public class CustomHibernateJpaAutoConfigurationTests {
 
@@ -57,7 +67,7 @@ public class CustomHibernateJpaAutoConfigurationTests {
 				"spring.datasource.driverClassName:com.mysql.jdbc.Driver",
 				"spring.datasource.url:jdbc:mysql://localhost/nonexistent",
 				"spring.datasource.initialize:false", "spring.jpa.database:MYSQL");
-		this.context.register(TestConfiguration.class, DataSourceAutoConfiguration.class,
+		this.context.register(TestConfiguration.class, MockDataSourceConfiguration.class,
 				PropertyPlaceholderAutoConfiguration.class,
 				HibernateJpaAutoConfiguration.class);
 		this.context.refresh();
@@ -101,10 +111,44 @@ public class CustomHibernateJpaAutoConfigurationTests {
 		assertThat(hibernateProperties.get("hibernate.ejb.naming_strategy")).isNull();
 	}
 
+	@Test
+	public void testDefaultDatabaseForH2() throws Exception {
+		EnvironmentTestUtils.addEnvironment(this.context,
+				"spring.datasource.driverClassName:org.h2.Driver",
+				"spring.datasource.url:jdbc:h2:mem:testdb",
+				"spring.datasource.initialize:false");
+		this.context.register(TestConfiguration.class, DataSourceAutoConfiguration.class,
+				PropertyPlaceholderAutoConfiguration.class,
+				HibernateJpaAutoConfiguration.class);
+		this.context.refresh();
+		HibernateJpaVendorAdapter bean = this.context.getBean(HibernateJpaVendorAdapter.class);
+		Database database = (Database) ReflectionTestUtils.getField(bean, "database");
+		assertThat(database).isEqualTo(Database.H2);
+	}
+
 	@Configuration
 	@TestAutoConfigurationPackage(City.class)
 	protected static class TestConfiguration {
 
 	}
 
+	@Configuration
+	protected static class MockDataSourceConfiguration {
+
+		@Bean
+		public DataSource dataSource() {
+			DataSource dataSource = mock(DataSource.class);
+			try {
+				given(dataSource.getConnection()).willReturn(mock(Connection.class));
+				given(dataSource.getConnection().getMetaData()).willReturn(
+						mock(DatabaseMetaData.class));
+			}
+			catch (SQLException e) {
+				//Do nothing
+			}
+			return dataSource;
+		}
+
+	}
+
 }

spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/orm/jpa/DatabasePlatformTests.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright 2012-2016 the original author or authors.
+ *
+ * Licensed 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.springframework.boot.autoconfigure.orm.jpa;
+
+import org.junit.Test;
+
+import org.springframework.boot.jdbc.DatabaseDriver;
+import org.springframework.orm.jpa.vendor.Database;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link DatabasePlatform}.
+ *
+ * @author Eddú Meléndez
+ */
+public class DatabasePlatformTests {
+
+	@Test
+	public void databaseDriverLookups() {
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.DB2))
+				.isEqualTo(DatabasePlatform.DB2);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.DERBY))
+				.isEqualTo(DatabasePlatform.DERBY);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.H2))
+				.isEqualTo(DatabasePlatform.H2);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.HSQLDB))
+				.isEqualTo(DatabasePlatform.HSQL);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.INFORMIX))
+				.isEqualTo(DatabasePlatform.INFORMIX);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.MYSQL))
+				.isEqualTo(DatabasePlatform.MYSQL);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.ORACLE))
+				.isEqualTo(DatabasePlatform.ORACLE);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.POSTGRESQL))
+				.isEqualTo(DatabasePlatform.POSTGRESQL);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.SQLSERVER))
+				.isEqualTo(DatabasePlatform.SQL_SERVER);
+	}
+
+	@Test
+	public void databaseLookups() {
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.DB2)
+				.getDatabase())
+				.isEqualTo(Database.DB2);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.DERBY)
+				.getDatabase())
+				.isEqualTo(Database.DERBY);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.H2)
+				.getDatabase())
+				.isEqualTo(Database.H2);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.HSQLDB)
+				.getDatabase())
+				.isEqualTo(Database.HSQL);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.INFORMIX)
+				.getDatabase())
+				.isEqualTo(Database.INFORMIX);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.MYSQL)
+				.getDatabase())
+				.isEqualTo(Database.MYSQL);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.ORACLE)
+				.getDatabase())
+				.isEqualTo(Database.ORACLE);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.POSTGRESQL)
+				.getDatabase())
+				.isEqualTo(Database.POSTGRESQL);
+		assertThat(DatabasePlatform.fromDatabaseDriver(DatabaseDriver.SQLSERVER)
+				.getDatabase())
+				.isEqualTo(Database.SQL_SERVER);
+	}
+
+}

spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/orm/jpa/JpaPropertiesTests.java

@@ -32,6 +32,7 @@ import org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy;
 import org.springframework.boot.test.util.EnvironmentTestUtils;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.orm.jpa.vendor.Database;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.entry;
@@ -166,6 +167,20 @@ public class JpaPropertiesTests {
 				.containsEntry(AvailableSettings.USE_NEW_ID_GENERATOR_MAPPINGS, "true");
 	}
 
+	@Test
+	public void determineH2DatabaseWhenJdbcUrlIsProvided() {
+		JpaProperties properties = load(HibernateVersion.V5);
+		Database database = properties.determineDatabase("jdbc:h2:mem:testdb");
+		assertThat(database).isEqualTo(Database.H2);
+	}
+
+	@Test
+	public void determineDefaultDatabaseWhenJdbcUrlIsProvided() {
+		JpaProperties properties = load(HibernateVersion.V5);
+		Database database = properties.determineDatabase("jdbc:unknown://localhost");
+		assertThat(database).isEqualTo(Database.DEFAULT);
+	}
+
 	@SuppressWarnings("unchecked")
 	private DataSource mockStandaloneDataSource() throws SQLException {
 		DataSource ds = mock(DataSource.class);