Allow BFPP to modify database initialization ordering

Fixes gh-26899

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/sql/init/dependency/DatabaseInitializationDependencyConfigurer.java

@@ -34,6 +34,7 @@ import org.springframework.beans.factory.support.BeanDefinitionRegistry;
 import org.springframework.boot.util.Instantiator;
 import org.springframework.context.annotation.Import;
 import org.springframework.context.annotation.ImportBeanDefinitionRegistrar;
+import org.springframework.core.Ordered;
 import org.springframework.core.env.Environment;
 import org.springframework.core.io.support.SpringFactoriesLoader;
 import org.springframework.core.type.AnnotationMetadata;
@@ -84,7 +85,7 @@ public class DatabaseInitializationDependencyConfigurer implements ImportBeanDef
 	 * {@link BeanFactoryPostProcessor} used to configure database initialization
 	 * dependency relationships.
 	 */
-	static class DependsOnDatabaseInitializationPostProcessor implements BeanFactoryPostProcessor {
+	static class DependsOnDatabaseInitializationPostProcessor implements BeanFactoryPostProcessor, Ordered {
 
 		private final Environment environment;
 
@@ -92,6 +93,11 @@ public class DatabaseInitializationDependencyConfigurer implements ImportBeanDef
 			this.environment = environment;
 		}
 
+		@Override
+		public int getOrder() {
+			return 0;
+		}
+
 		@Override
 		public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) {
 			Set<String> initializerBeanNames = detectInitializerBeanNames(beanFactory);

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/sql/init/dependency/DatabaseInitializationDependencyConfigurerTests.java

@@ -24,7 +24,10 @@ import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Enumeration;
+import java.util.HashMap;
 import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
 import java.util.Properties;
 import java.util.Set;
 import java.util.function.Consumer;
@@ -35,9 +38,11 @@ import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
 
 import org.springframework.beans.factory.config.BeanDefinition;
+import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 import org.springframework.beans.factory.support.BeanDefinitionBuilder;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
 import org.springframework.core.Ordered;
@@ -70,6 +75,30 @@ class DatabaseInitializationDependencyConfigurerTests {
 				MockedDependsOnDatabaseInitializationDetector.instance);
 	}
 
+	@Test
+	void beanFactoryPostProcessorHasOrderAllowingSubsequentPostProcessorsToFineTuneDependencies() {
+		performDetection(Arrays.asList(MockDatabaseInitializerDetector.class,
+				MockedDependsOnDatabaseInitializationDetector.class), (context) -> {
+					BeanDefinition alpha = BeanDefinitionBuilder.genericBeanDefinition(String.class)
+							.getBeanDefinition();
+					BeanDefinition bravo = BeanDefinitionBuilder.genericBeanDefinition(String.class)
+							.getBeanDefinition();
+					context.register(DependsOnCaptor.class);
+					context.register(DependencyConfigurerConfiguration.class);
+					context.registerBeanDefinition("alpha", alpha);
+					context.registerBeanDefinition("bravo", bravo);
+					given(MockDatabaseInitializerDetector.instance.detect(context.getBeanFactory()))
+							.willReturn(Collections.singleton("alpha"));
+					given(MockedDependsOnDatabaseInitializationDetector.instance.detect(context.getBeanFactory()))
+							.willReturn(Collections.singleton("bravo"));
+					context.refresh();
+					assertThat(DependsOnCaptor.dependsOn).hasEntrySatisfying("bravo",
+							(dependencies) -> assertThat(dependencies).containsExactly("alpha"));
+					assertThat(DependsOnCaptor.dependsOn).hasEntrySatisfying("alpha",
+							(dependencies) -> assertThat(dependencies).isEmpty());
+				});
+	}
+
 	@Test
 	void whenDetectorsAreCreatedThenTheEnvironmentCanBeInjected() {
 		performDetection(Arrays.asList(ConstructorInjectionDatabaseInitializerDetector.class,
@@ -77,6 +106,7 @@ class DatabaseInitializationDependencyConfigurerTests {
 					BeanDefinition alpha = BeanDefinitionBuilder.genericBeanDefinition(String.class)
 							.getBeanDefinition();
 					context.registerBeanDefinition("alpha", alpha);
+					context.register(DependencyConfigurerConfiguration.class);
 					context.refresh();
 					assertThat(ConstructorInjectionDatabaseInitializerDetector.environment).isEqualTo(this.environment);
 					assertThat(ConstructorInjectionDependsOnDatabaseInitializationDetector.environment)
@@ -96,6 +126,7 @@ class DatabaseInitializationDependencyConfigurerTests {
 							.willReturn(Collections.singleton("alpha"));
 					given(MockedDependsOnDatabaseInitializationDetector.instance.detect(context.getBeanFactory()))
 							.willReturn(Collections.singleton("bravo"));
+					context.register(DependencyConfigurerConfiguration.class);
 					context.refresh();
 					assertThat(alpha.getAttribute(DatabaseInitializerDetector.class.getName()))
 							.isEqualTo(MockDatabaseInitializerDetector.class.getName());
@@ -123,6 +154,7 @@ class DatabaseInitializationDependencyConfigurerTests {
 					context.registerBeanDefinition("alpha", alpha);
 					context.registerBeanDefinition("bravo", bravo);
 					context.registerBeanDefinition("charlie", charlie);
+					context.register(DependencyConfigurerConfiguration.class);
 					context.refresh();
 					assertThat(charlie.getDependsOn()).containsExactly("alpha", "bravo");
 					assertThat(bravo.getDependsOn()).containsExactly("alpha");
@@ -137,7 +169,6 @@ class DatabaseInitializationDependencyConfigurerTests {
 		try (AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext()) {
 			context.setEnvironment(this.environment);
 			context.setClassLoader(detectorSpringFactories);
-			context.register(DependencyConfigurerConfiguration.class);
 			contextCallback.accept(context);
 		}
 	}
@@ -270,4 +301,28 @@ class DatabaseInitializationDependencyConfigurerTests {
 
 	}
 
+	@Configuration(proxyBeanMethods = false)
+	static class DependsOnCaptor {
+
+		static final Map<String, List<String>> dependsOn = new HashMap<>();
+
+		@Bean
+		static BeanFactoryPostProcessor dependsOnCapturingPostProcessor() {
+			return (beanFactory) -> {
+				dependsOn.clear();
+				for (String name : beanFactory.getBeanDefinitionNames()) {
+					storeDependsOn(name, beanFactory);
+				}
+			};
+		}
+
+		private static void storeDependsOn(String name, ConfigurableListableBeanFactory beanFactory) {
+			String[] dependsOn = beanFactory.getBeanDefinition(name).getDependsOn();
+			if (dependsOn != null) {
+				DependsOnCaptor.dependsOn.put(name, Arrays.asList(dependsOn));
+			}
+		}
+
+	}
+
 }