Add native-image support for Flyway

The Flyway smoke tests currently fail with GraalVM complaining about proxy generation, which could be related to @FlywayDataSource:

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'dataSource': Unsatisfied dependency expressed through method 'dataSource' parameter 0: Error creating bean with name 'spring.datasource-org.springframework.boot.autoconfigure.jdbc.DataSourceProperties': Proxy class defined by interfaces [interface org.springframework.beans.factory.annotation.Qualifier, interface org.springframework.core.annotation.SynthesizedAnnotation] not found. Generating proxy classes at runtime is not supported. Proxy classes need to be defined at image build time by specifying the list of interfaces that they implement. To define proxy classes use -H:DynamicProxyConfigurationFiles=<comma-separated-config-files> and -H:DynamicProxyConfigurationResources=<comma-separated-config-resources> options.
	at org.springframework.beans.factory.aot.BeanInstanceSupplier.resolveArgument(BeanInstanceSupplier.java:349) ~[na:na]
	at org.springframework.beans.factory.aot.BeanInstanceSupplier.resolveArguments(BeanInstanceSupplier.java:265) ~[na:na]
	at org.springframework.beans.factory.aot.BeanInstanceSupplier.get(BeanInstanceSupplier.java:208) ~[na:na]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.obtainInstanceFromSupplier(AbstractAutowireCapableBeanFactory.java:1224) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.obtainFromSupplier(AbstractAutowireCapableBeanFactory.java:1209) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1156) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:566) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:526) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:326) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:324) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:200) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:930) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:926) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:592) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:731) ~[flyway:3.0.0-SNAPSHOT]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:430) ~[flyway:3.0.0-SNAPSHOT]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:312) ~[flyway:3.0.0-SNAPSHOT]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1303) ~[flyway:3.0.0-SNAPSHOT]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1292) ~[flyway:3.0.0-SNAPSHOT]
	at com.example.flyway.FlywayApplication.main(FlywayApplication.java:13) ~[flyway:na]
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'spring.datasource-org.springframework.boot.autoconfigure.jdbc.DataSourceProperties': Proxy class defined by interfaces [interface org.springframework.beans.factory.annotation.Qualifier, interface org.springframework.core.annotation.SynthesizedAnnotation] not found. Generating proxy classes at runtime is not supported. Proxy classes need to be defined at image build time by specifying the list of interfaces that they implement. To define proxy classes use -H:DynamicProxyConfigurationFiles=<comma-separated-config-files> and -H:DynamicProxyConfigurationResources=<comma-separated-config-resources> options.
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:611) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:526) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:326) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:324) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:200) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:254) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1374) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1294) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.aot.BeanInstanceSupplier.resolveArgument(BeanInstanceSupplier.java:332) ~[na:na]
	... 20 common frames omitted
Caused by: com.oracle.svm.core.jdk.UnsupportedFeatureError: Proxy class defined by interfaces [interface org.springframework.beans.factory.annotation.Qualifier, interface org.springframework.core.annotation.SynthesizedAnnotation] not found. Generating proxy classes at runtime is not supported. Proxy classes need to be defined at image build time by specifying the list of interfaces that they implement. To define proxy classes use -H:DynamicProxyConfigurationFiles=<comma-separated-config-files> and -H:DynamicProxyConfigurationResources=<comma-separated-config-resources> options.
	at com.oracle.svm.core.util.VMError.unsupportedFeature(VMError.java:89) ~[na:na]
	at com.oracle.svm.reflect.proxy.DynamicProxySupport.getProxyClass(DynamicProxySupport.java:158) ~[na:na]
	at java.lang.reflect.Proxy.getProxyConstructor(Proxy.java:48) ~[flyway:na]
	at java.lang.reflect.Proxy.newProxyInstance(Proxy.java:1037) ~[flyway:na]
	at org.springframework.core.annotation.SynthesizedMergedAnnotationInvocationHandler.createProxy(SynthesizedMergedAnnotationInvocationHandler.java:305) ~[na:na]
	at org.springframework.core.annotation.TypeMappedAnnotation.createSynthesizedAnnotation(TypeMappedAnnotation.java:333) ~[na:na]
	at org.springframework.core.annotation.AbstractMergedAnnotation.synthesize(AbstractMergedAnnotation.java:210) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.core.annotation.AbstractMergedAnnotation.synthesize(AbstractMergedAnnotation.java:200) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.core.annotation.AnnotationUtils.getAnnotation(AnnotationUtils.java:227) ~[na:na]
	at org.springframework.core.annotation.AnnotationUtils.getAnnotation(AnnotationUtils.java:252) ~[na:na]
	at org.springframework.beans.factory.annotation.BeanFactoryAnnotationUtils.isQualifierMatch(BeanFactoryAnnotationUtils.java:182) ~[na:na]
	at org.springframework.beans.factory.annotation.BeanFactoryAnnotationUtils.qualifiedBeansOfType(BeanFactoryAnnotationUtils.java:68) ~[na:na]
	at org.springframework.boot.context.properties.ConversionServiceDeducer$ConverterBeans.beans(ConversionServiceDeducer.java:99) ~[na:na]
	at org.springframework.boot.context.properties.ConversionServiceDeducer$ConverterBeans.<init>(ConversionServiceDeducer.java:93) ~[na:na]
	at org.springframework.boot.context.properties.ConversionServiceDeducer.getConversionServices(ConversionServiceDeducer.java:65) ~[na:na]
	at org.springframework.boot.context.properties.ConversionServiceDeducer.getConversionServices(ConversionServiceDeducer.java:55) ~[na:na]
	at org.springframework.boot.context.properties.ConfigurationPropertiesBinder.getConversionServices(ConfigurationPropertiesBinder.java:183) ~[flyway:na]
	at org.springframework.boot.context.properties.ConfigurationPropertiesBinder.getBinder(ConfigurationPropertiesBinder.java:168) ~[flyway:na]
	at org.springframework.boot.context.properties.ConfigurationPropertiesBinder.bind(ConfigurationPropertiesBinder.java:95) ~[flyway:na]
	at org.springframework.boot.context.properties.ConfigurationPropertiesBindingPostProcessor.bind(ConfigurationPropertiesBindingPostProcessor.java:89) ~[flyway:na]
	at org.springframework.boot.context.properties.ConfigurationPropertiesBindingPostProcessor.postProcessBeforeInitialization(ConfigurationPropertiesBindingPostProcessor.java:78) ~[flyway:na]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsBeforeInitialization(AbstractAutowireCapableBeanFactory.java:425) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1745) ~[flyway:6.0.0-SNAPSHOT]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:604) ~[flyway:6.0.0-SNAPSHOT]
	... 29 common frames omitted

[mhalbritter]

I’m not 100% convinced that the scanner created by NativeImageResourceProviderCustomizer behaves exactly the same as the default one from Flyway. That’s the reason I was hesitant to always use the NativeImageResourceProviderCustomizer on JVM and on native image.

[mhalbritter]

Even if GraalVM team / Flyway team doesn’t want to support it by themselves, I found a better workaround than to look for the migrations at AOT phase: Implement a Flyway custom ResourceProvider which uses the resource: scheme from GraalVM to find the migrations. The PoC is here: https://github.com/mhalbritter/flyway-native-image

All that is left with this ResourceProvider in place is resource hints on db/migration/*.sql (or whatever the user has configured).

Drawback of that approach is that, when the custom ResourceProvider is in place, it get’s called for all migration locations, maybe even one with filesystem: or s3: prefixes. It would be nice to delegate this back to the default ResourceProvider, but it doesn’t seem like there is an easy way to do that.