Switch default to fail on error in SQL initialization

User can switch the behaviour on and off with
spring.datasource.continueOnError:true|false. I decided
not to add an extra nested level of property resolution
because of the existing spring.datasource.schema
(and other properties relating to initialization) because
concision seemed like a good thing with those more common
settings.

Fixes spring-projectsgh-374

docs/howto.md

@@ -901,14 +901,16 @@ enables it by default and loads SQL from the standard locations
 `schema.sql` and `data.sql` (in the root of the classpath). In
 addition Spring Boot will load a file `schema-${platform}.sql` where
 `platform` is the vendor name of the database (`hsqldb`, `h2,
-`oracle`, `mysql`, `postgresql` etc.). Spring Boot *disables* the
-failfast feature of the Spring JDBC initializer, so if the scripts
-cause exceptions they will be logged, but the application will still
-start. This is so that they can be used as "poor man's migrations"
-(inserts that fail mean that the data is already there, so no need to
-fail for instance), but it does mean that you need to test the state
-of your database on startup if you want to be sure that it was
-successful (or else monitor the Spring JDBC DEBUG logs).
+`oracle`, `mysql`, `postgresql` etc.). Spring Boot enables the
+failfast feature of the Spring JDBC initializer by default, so if 
+the scripts cause exceptions the application will fail.
+
+To disable the failfast you can set
+`spring.datasource.continueOnError=true`. This can be useful once an
+application has matured and been deployed a few times, since the
+scripts can act as "poor man's migrations" - inserts that fail mean
+that the data is already there, so there would be no need to prevent
+the application from running, for instance.
 
 ### Higher Level Migration Tools
 

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

@@ -106,13 +106,15 @@ protected void initialize() throws Exception {
 					.getResources(schemaLocation)));
 		}
 
+		boolean continueOnError = this.environment.getProperty("continueOnError",
+				Boolean.class, false);
 		boolean exists = false;
 		ResourceDatabasePopulator populator = new ResourceDatabasePopulator();
 		for (Resource resource : resources) {
 			if (resource.exists()) {
 				exists = true;
 				populator.addScript(resource);
-				populator.setContinueOnError(true);
+				populator.setContinueOnError(continueOnError);
 			}
 		}
 

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

@@ -24,11 +24,13 @@
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Properties;
+import java.util.Random;
 import java.util.logging.Logger;
 
 import javax.sql.DataSource;
 
 import org.apache.commons.dbcp.BasicDataSource;
+import org.junit.Before;
 import org.junit.Test;
 import org.mockito.Mockito;
 import org.springframework.boot.autoconfigure.PropertyPlaceholderAutoConfiguration;
@@ -56,6 +58,13 @@ public class DataSourceAutoConfigurationTests {
 
 	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 
+	@Before
+	public void init() {
+		EnvironmentTestUtils.addEnvironment(this.context,
+				"spring.datasource.initialize:false",
+				"spring.datasource.url:jdbc:hsqldb:mem:testdb-" + new Random().nextInt());
+	}
+
 	@Test
 	public void testDefaultDataSourceExists() throws Exception {
 		this.context.register(DataSourceAutoConfiguration.class,
@@ -85,8 +94,7 @@ public void testExplicitDriverClassClearsUserName() throws Exception {
 				.addEnvironment(
 						this.context,
 						"spring.datasource.driverClassName:org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfigurationTests$DatabaseDriver",
-						"spring.datasource.url:jdbc:foo://localhost",
-						"spring.datasource.initialize:false");
+						"spring.datasource.url:jdbc:foo://localhost");
 		this.context.register(DataSourceAutoConfiguration.class,
 				PropertyPlaceholderAutoConfiguration.class);
 		this.context.refresh();
@@ -141,6 +149,8 @@ public void testNamedParameterJdbcTemplateExists() throws Exception {
 
 	@Test
 	public void testDataSourceInitialized() throws Exception {
+		EnvironmentTestUtils.addEnvironment(this.context,
+				"spring.datasource.initialize:true");
 		this.context.register(DataSourceAutoConfiguration.class,
 				PropertyPlaceholderAutoConfiguration.class);
 		this.context.refresh();
@@ -172,16 +182,17 @@ public void testDataSourceInitializedWithExplicitScript() throws Exception {
 
 	@Test
 	public void testDataSourceInitializedWithMultipleScripts() throws Exception {
-		this.context.register(DataSourceAutoConfiguration.class,
-				PropertyPlaceholderAutoConfiguration.class);
-		Map<String, Object> map = new HashMap<String, Object>();
-		map.put(DataSourceAutoConfiguration.CONFIGURATION_PREFIX + ".schema",
-				ClassUtils.addResourcePathToPackagePath(getClass(), "schema.sql")
+		EnvironmentTestUtils.addEnvironment(
+				this.context,
+				"spring.datasource.initialize:true",
+				"spring.datasource.schema:"
+						+ ClassUtils.addResourcePathToPackagePath(getClass(),
+								"schema.sql")
 						+ ","
 						+ ClassUtils.addResourcePathToPackagePath(getClass(),
 								"another.sql"));
-		this.context.getEnvironment().getPropertySources()
-				.addFirst(new MapPropertySource("test", map));
+		this.context.register(DataSourceAutoConfiguration.class,
+				PropertyPlaceholderAutoConfiguration.class);
 		this.context.refresh();
 		DataSource dataSource = this.context.getBean(DataSource.class);
 		assertTrue(dataSource instanceof org.apache.tomcat.jdbc.pool.DataSource);

spring-boot-autoconfigure/src/test/resources/application.properties

@@ -1 +1 @@
-foo: bucket
+foo: bucket

spring-boot/src/main/java/org/springframework/boot/test/EnvironmentTestUtils.java

@@ -24,6 +24,7 @@
 import org.springframework.core.env.ConfigurableEnvironment;
 import org.springframework.core.env.Environment;
 import org.springframework.core.env.MapPropertySource;
+import org.springframework.core.env.MutablePropertySources;
 
 /**
  * Test utilities for setting environment values.
@@ -54,15 +55,26 @@ public static void addEnvironment(ConfigurableApplicationContext context,
 	 */
 	public static void addEnvironment(ConfigurableEnvironment environment,
 			String... pairs) {
-		Map<String, Object> map = new HashMap<String, Object>();
+		MutablePropertySources sources = environment.getPropertySources();
+		Map<String, Object> map;
+		if (!sources.contains("test")) {
+			map = new HashMap<String, Object>();
+			MapPropertySource source = new MapPropertySource("test", map);
+			sources.addFirst(source);
+		}
+		else {
+			@SuppressWarnings("unchecked")
+			Map<String, Object> value = (Map<String, Object>) sources.get("test")
+					.getSource();
+			map = value;
+		}
 		for (String pair : pairs) {
 			int index = pair.indexOf(":");
 			index = index < 0 ? index = pair.indexOf("=") : index;
 			String key = pair.substring(0, index > 0 ? index : pair.length());
 			String value = index > 0 ? pair.substring(index + 1) : "";
 			map.put(key.trim(), value.trim());
 		}
-		environment.getPropertySources().addFirst(new MapPropertySource("test", map));
 	}
 
 }