Do not default username/password for DataSource unless embedded

To use a DataSource pool (Tomcat or DBCP) the user must supply a valid
driver class name *and* database URL. If both are supplied and the
driver class is not one of the embedded ones, then no default username
or password is provided.

Fixes gh-94

spring-boot-autoconfigure/pom.xml

@@ -174,6 +174,11 @@
 			<artifactId>hsqldb</artifactId>
 			<scope>test</scope>
 		</dependency>
+		<dependency>
+			<groupId>mysql</groupId>
+			<artifactId>mysql-connector-java</artifactId>
+			<scope>test</scope>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework</groupId>
 			<artifactId>spring-test</artifactId>

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jdbc/AbstractDataSourceConfiguration.java

@@ -18,6 +18,7 @@ package org.springframework.boot.autoconfigure.jdbc;
 
 import org.springframework.beans.factory.BeanClassLoaderAware;
 import org.springframework.beans.factory.BeanCreationException;
+import org.springframework.beans.factory.InitializingBean;
 import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.util.StringUtils;
@@ -29,15 +30,16 @@ import org.springframework.util.StringUtils;
  */
 @ConfigurationProperties(name = DataSourceAutoConfiguration.CONFIGURATION_PREFIX)
 @EnableConfigurationProperties
-public abstract class AbstractDataSourceConfiguration implements BeanClassLoaderAware {
+public abstract class AbstractDataSourceConfiguration implements BeanClassLoaderAware,
+		InitializingBean {
 
 	private String driverClassName;
 
 	private String url;
 
-	private String username = "sa";
+	private String username;
 
-	private String password = "";
+	private String password;
 
 	private int maxActive = 100;
 
@@ -53,41 +55,67 @@ public abstract class AbstractDataSourceConfiguration implements BeanClassLoader
 
 	private ClassLoader classLoader;
 
+	private EmbeddedDatabaseConnection embeddedDatabaseConnection = EmbeddedDatabaseConnection.NONE;
+
 	@Override
 	public void setBeanClassLoader(ClassLoader classLoader) {
 		this.classLoader = classLoader;
 	}
 
+	@Override
+	public void afterPropertiesSet() throws Exception {
+		this.embeddedDatabaseConnection = EmbeddedDatabaseConnection
+				.get(this.classLoader);
+	}
+
 	protected String getDriverClassName() {
 		if (StringUtils.hasText(this.driverClassName)) {
 			return this.driverClassName;
 		}
-		EmbeddedDatabaseConnection embeddedDatabaseConnection = EmbeddedDatabaseConnection
-				.get(this.classLoader);
-		this.driverClassName = embeddedDatabaseConnection.getDriverClassName();
-		if (!StringUtils.hasText(this.driverClassName)) {
+		String driverClassName = this.embeddedDatabaseConnection.getDriverClassName();
+		if (!StringUtils.hasText(driverClassName)) {
 			throw new BeanCreationException(
 					"Cannot determine embedded database driver class for database type "
-							+ embeddedDatabaseConnection + ". If you want an embedded "
-							+ "database please put a supoprted one on the classpath.");
+							+ this.embeddedDatabaseConnection
+							+ ". If you want an embedded "
+							+ "database please put a supported one on the classpath.");
 		}
-		return this.driverClassName;
+		return driverClassName;
 	}
 
 	protected String getUrl() {
 		if (StringUtils.hasText(this.url)) {
 			return this.url;
 		}
-		EmbeddedDatabaseConnection embeddedDatabaseConnection = EmbeddedDatabaseConnection
-				.get(this.classLoader);
-		this.url = embeddedDatabaseConnection.getUrl();
-		if (!StringUtils.hasText(this.url)) {
+		String url = this.embeddedDatabaseConnection.getUrl();
+		if (!StringUtils.hasText(url)) {
 			throw new BeanCreationException(
 					"Cannot determine embedded database url for database type "
-							+ embeddedDatabaseConnection + ". If you want an embedded "
+							+ this.embeddedDatabaseConnection
+							+ ". If you want an embedded "
 							+ "database please put a supported on on the classpath.");
 		}
-		return this.url;
+		return url;
+	}
+
+	protected String getUsername() {
+		if (StringUtils.hasText(this.username)) {
+			return this.username;
+		}
+		if (EmbeddedDatabaseConnection.isEmbedded(this.driverClassName)) {
+			return "sa";
+		}
+		return null;
+	}
+
+	protected String getPassword() {
+		if (StringUtils.hasText(this.password)) {
+			return this.password;
+		}
+		if (EmbeddedDatabaseConnection.isEmbedded(this.driverClassName)) {
+			return "";
+		}
+		return null;
 	}
 
 	public void setDriverClassName(String driverClassName) {
@@ -130,14 +158,6 @@ public abstract class AbstractDataSourceConfiguration implements BeanClassLoader
 		this.testOnReturn = testOnReturn;
 	}
 
-	protected String getUsername() {
-		return this.username;
-	}
-
-	protected String getPassword() {
-		return this.password;
-	}
-
 	protected int getMaxActive() {
 		return this.maxActive;
 	}

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jdbc/CommonsDataSourceConfiguration.java

@@ -49,8 +49,12 @@ public class CommonsDataSourceConfiguration extends AbstractDataSourceConfigurat
 		this.pool = new BasicDataSource();
 		this.pool.setDriverClassName(getDriverClassName());
 		this.pool.setUrl(getUrl());
+		if (getUsername() != null) {
 			this.pool.setUsername(getUsername());
+		}
+		if (getPassword() != null) {
 			this.pool.setPassword(getPassword());
+		}
 		this.pool.setMaxActive(getMaxActive());
 		this.pool.setMaxIdle(getMaxIdle());
 		this.pool.setMinIdle(getMinIdle());

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jdbc/EmbeddedDatabaseConnection.java

@@ -88,6 +88,20 @@ public enum EmbeddedDatabaseConnection {
 	 */
 	static EmbeddedDatabaseConnection override;
 
+	/**
+	 * Convenience method to determine if a given driver class name represents an embedded
+	 * database type.
+	 * 
+	 * @param driverClass the driver class
+	 * @return true if the driver class is one of the embedded types
+	 */
+	public static boolean isEmbedded(String driverClass) {
+		return driverClass != null
+				&& (driverClass.equals(HSQL.driverClass)
+						|| driverClass.equals(H2.driverClass) || driverClass
+							.equals(DERBY.driverClass));
+	}
+
 	/**
 	 * Returns the most suitable {@link EmbeddedDatabaseConnection} for the given class
 	 * loader.

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jdbc/TomcatDataSourceConfiguration.java

@@ -39,8 +39,12 @@ public class TomcatDataSourceConfiguration extends AbstractDataSourceConfigurati
 		this.pool = new org.apache.tomcat.jdbc.pool.DataSource();
 		this.pool.setDriverClassName(getDriverClassName());
 		this.pool.setUrl(getUrl());
+		if (getUsername() != null) {
 			this.pool.setUsername(getUsername());
+		}
+		if (getPassword() != null) {
 			this.pool.setPassword(getPassword());
+		}
 		this.pool.setMaxActive(getMaxActive());
 		this.pool.setMaxIdle(getMaxIdle());
 		this.pool.setMinIdle(getMinIdle());

spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/DataSourceAutoConfigurationTests.java

@@ -23,6 +23,7 @@ import javax.sql.DataSource;
 
 import org.apache.commons.dbcp.BasicDataSource;
 import org.junit.Test;
+import org.springframework.boot.TestUtils;
 import org.springframework.boot.autoconfigure.PropertyPlaceholderAutoConfiguration;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.context.annotation.Bean;
@@ -35,6 +36,7 @@ import org.springframework.util.ClassUtils;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 
 /**
@@ -54,6 +56,36 @@ public class DataSourceAutoConfigurationTests {
 		assertNotNull(this.context.getBean(DataSource.class));
 	}
 
+	@Test
+	public void testEmbeddedTypeDefaultsUsername() throws Exception {
+		TestUtils.addEnviroment(this.context,
+				"spring.datasource.driverClassName:org.hsqldb.jdbcDriver",
+				"spring.datasource.url:jdbc:hsqldb:mem:testdb");
+		this.context.register(DataSourceAutoConfiguration.class,
+				PropertyPlaceholderAutoConfiguration.class);
+		this.context.refresh();
+		DataSource bean = this.context.getBean(DataSource.class);
+		assertNotNull(bean);
+		org.apache.tomcat.jdbc.pool.DataSource pool = (org.apache.tomcat.jdbc.pool.DataSource) bean;
+		assertEquals("org.hsqldb.jdbcDriver", pool.getDriverClassName());
+		assertEquals("sa", pool.getUsername());
+	}
+
+	@Test
+	public void testExplicitDriverClassClearsUserName() throws Exception {
+		TestUtils.addEnviroment(this.context,
+				"spring.datasource.driverClassName:com.mysql.jdbc.Driver",
+				"spring.datasource.url:jdbc:mysql://localhost");
+		this.context.register(DataSourceAutoConfiguration.class,
+				PropertyPlaceholderAutoConfiguration.class);
+		this.context.refresh();
+		DataSource bean = this.context.getBean(DataSource.class);
+		assertNotNull(bean);
+		org.apache.tomcat.jdbc.pool.DataSource pool = (org.apache.tomcat.jdbc.pool.DataSource) bean;
+		assertEquals("com.mysql.jdbc.Driver", pool.getDriverClassName());
+		assertNull(pool.getUsername());
+	}
+
 	@Test
 	public void testDefaultDataSourceCanBeOverridden() throws Exception {
 		this.context.register(TestDataSourceConfiguration.class,

spring-boot-dependencies/pom.xml

@@ -28,6 +28,7 @@
 		<log4j.version>1.2.17</log4j.version>
 		<logback.version>1.0.13</logback.version>
 		<mockito.version>1.9.5</mockito.version>
+		<mysql.version>5.1.23</mysql.version>
 		<reactor.version>1.0.0.M3</reactor.version>
 		<servlet-api.version>3.0.1</servlet-api.version>
 		<slf4j.version>1.7.5</slf4j.version>
@@ -104,6 +105,11 @@
 				<artifactId>log4j</artifactId>
 				<version>${log4j.version}</version>
 			</dependency>
+			<dependency>
+				<groupId>mysql</groupId>
+				<artifactId>mysql-connector-java</artifactId>
+				<version>${mysql.version}</version>
+			</dependency>
 			<dependency>
 				<groupId>nz.net.ultraq.thymeleaf</groupId>
 				<artifactId>thymeleaf-layout-dialect</artifactId>