Merge pull request #16850 from Ilya Lukyanovich

* gh-16850:
  Polish "Auto-configure Flyway and Liquibase when there's a URL but no DataSource"
  Auto-configure Flyway and Liquibase when there's a URL but no DataSource

Closes gh-16850

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/flyway/FlywayAutoConfiguration.java

@@ -36,11 +36,13 @@ import org.flywaydb.core.api.configuration.FluentConfiguration;
 import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.boot.autoconfigure.AutoConfigureAfter;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.autoconfigure.condition.AnyNestedCondition;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.boot.autoconfigure.data.jpa.EntityManagerFactoryDependsOnPostProcessor;
+import org.springframework.boot.autoconfigure.flyway.FlywayAutoConfiguration.FlywayDataSourceCondition;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceProperties;
 import org.springframework.boot.autoconfigure.jdbc.JdbcOperationsDependsOnPostProcessor;
@@ -52,6 +54,7 @@ import org.springframework.boot.context.properties.EnableConfigurationProperties
 import org.springframework.boot.context.properties.PropertyMapper;
 import org.springframework.boot.jdbc.DatabaseDriver;
 import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Conditional;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.core.convert.converter.GenericConverter;
@@ -82,7 +85,7 @@ import org.springframework.util.StringUtils;
 @SuppressWarnings("deprecation")
 @Configuration(proxyBeanMethods = false)
 @ConditionalOnClass(Flyway.class)
-@ConditionalOnBean(DataSource.class)
+@Conditional(FlywayDataSourceCondition.class)
 @ConditionalOnProperty(prefix = "spring.flyway", name = "enabled", matchIfMissing = true)
 @AutoConfigureAfter({ DataSourceAutoConfiguration.class,
 		JdbcTemplateAutoConfiguration.class, HibernateJpaAutoConfiguration.class })
@@ -462,4 +465,23 @@ public class FlywayAutoConfiguration {
 
 	}
 
+	static final class FlywayDataSourceCondition extends AnyNestedCondition {
+
+		FlywayDataSourceCondition() {
+			super(ConfigurationPhase.REGISTER_BEAN);
+		}
+
+		@ConditionalOnBean(DataSource.class)
+		private static final class DataSourceBeanCondition {
+
+		}
+
+		@ConditionalOnProperty(prefix = "spring.flyway", name = "url",
+				matchIfMissing = false)
+		private static final class FlywayUrlCondition {
+
+		}
+
+	}
+
 }

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/liquibase/LiquibaseAutoConfiguration.java

@@ -28,6 +28,7 @@ import liquibase.integration.spring.SpringLiquibase;
 import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.boot.autoconfigure.AutoConfigureAfter;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.autoconfigure.condition.AnyNestedCondition;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
@@ -37,10 +38,12 @@ import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceProperties;
 import org.springframework.boot.autoconfigure.jdbc.JdbcOperationsDependsOnPostProcessor;
 import org.springframework.boot.autoconfigure.jdbc.NamedParameterJdbcOperationsDependsOnPostProcessor;
+import org.springframework.boot.autoconfigure.liquibase.LiquibaseAutoConfiguration.LiquibaseDataSourceCondition;
 import org.springframework.boot.autoconfigure.orm.jpa.HibernateJpaAutoConfiguration;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.boot.jdbc.DataSourceBuilder;
 import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Conditional;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
 import org.springframework.core.io.Resource;
@@ -65,9 +68,9 @@ import org.springframework.util.Assert;
  */
 @Configuration(proxyBeanMethods = false)
 @ConditionalOnClass({ SpringLiquibase.class, DatabaseChange.class })
-@ConditionalOnBean(DataSource.class)
 @ConditionalOnProperty(prefix = "spring.liquibase", name = "enabled",
 		matchIfMissing = true)
+@Conditional(LiquibaseDataSourceCondition.class)
 @AutoConfigureAfter({ DataSourceAutoConfiguration.class,
 		HibernateJpaAutoConfiguration.class })
 public class LiquibaseAutoConfiguration {
@@ -225,4 +228,23 @@ public class LiquibaseAutoConfiguration {
 
 	}
 
+	static final class LiquibaseDataSourceCondition extends AnyNestedCondition {
+
+		LiquibaseDataSourceCondition() {
+			super(ConfigurationPhase.REGISTER_BEAN);
+		}
+
+		@ConditionalOnBean(DataSource.class)
+		private static final class DataSourceBeanCondition {
+
+		}
+
+		@ConditionalOnProperty(prefix = "spring.liquibase", name = "url",
+				matchIfMissing = false)
+		private static final class LiquibaseUrlCondition {
+
+		}
+
+	}
+
 }

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/flyway/FlywayAutoConfigurationTests.java

@@ -79,11 +79,22 @@ public class FlywayAutoConfigurationTests {
 			.withPropertyValues("spring.datasource.generate-unique-name=true");
 
 	@Test
-	public void noDataSource() {
+	public void backsOffWithNoDataSourceBeanAndNoFlywayUrl() {
 		this.contextRunner
 				.run((context) -> assertThat(context).doesNotHaveBean(Flyway.class));
 	}
 
+	@Test
+	public void createsDataSourceWithNoDataSourceBeanAndFlywayUrl() {
+		this.contextRunner
+				.withPropertyValues(
+						"spring.flyway.url:jdbc:hsqldb:mem:" + UUID.randomUUID())
+				.run((context) -> {
+					assertThat(context).hasSingleBean(Flyway.class);
+					assertThat(context.getBean(Flyway.class).getDataSource()).isNotNull();
+				});
+	}
+
 	@Test
 	public void createDataSourceWithUrl() {
 		this.contextRunner.withUserConfiguration(EmbeddedDataSourceConfiguration.class)

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/liquibase/LiquibaseAutoConfigurationTests.java

@@ -78,11 +78,23 @@ public class LiquibaseAutoConfigurationTests {
 			.withPropertyValues("spring.datasource.generate-unique-name=true");
 
 	@Test
-	public void noDataSource() {
+	public void backsOffWithNoDataSourceBeanAndNoLiquibaseUrl() {
 		this.contextRunner.run(
 				(context) -> assertThat(context).doesNotHaveBean(SpringLiquibase.class));
 	}
 
+	@Test
+	public void createsDataSourceWithNoDataSourceBeanAndLiquibaseUrl() {
+		this.contextRunner
+				.withPropertyValues("spring.liquibase.url:jdbc:hsqldb:mem:liquibase")
+				.run(assertLiquibase((liquibase) -> {
+					DataSource dataSource = liquibase.getDataSource();
+					assertThat(((HikariDataSource) dataSource).isClosed()).isTrue();
+					assertThat(((HikariDataSource) dataSource).getJdbcUrl())
+							.isEqualTo("jdbc:hsqldb:mem:liquibase");
+				}));
+	}
+
 	@Test
 	public void defaultSpringLiquibase() {
 		this.contextRunner.withUserConfiguration(EmbeddedDataSourceConfiguration.class)