Use BeanRegistrationAotProcessor to provide hints for auditing.

This avoids having to touch modules to add something like ImportRuntimeHints(AuditingHints.ReactiveAuditingRuntimeHints.class) to the enabled auditing annotations.

Original Pull Request: #2624

src/main/java/org/springframework/data/aot/AuditingBeanRegistrationAotProcessor.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright 2022 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.aot;
+
+import org.springframework.beans.factory.aot.BeanRegistrationAotContribution;
+import org.springframework.beans.factory.aot.BeanRegistrationAotProcessor;
+import org.springframework.beans.factory.support.RegisteredBean;
+import org.springframework.data.aot.hint.AuditingHints;
+import org.springframework.data.domain.AuditorAware;
+import org.springframework.data.domain.ReactiveAuditorAware;
+import org.springframework.data.repository.util.ReactiveWrappers;
+import org.springframework.data.repository.util.ReactiveWrappers.ReactiveLibrary;
+import org.springframework.lang.Nullable;
+import org.springframework.util.ClassUtils;
+
+/**
+ * @author Christoph Strobl
+ * @since 3.0
+ */
+public class AuditingBeanRegistrationAotProcessor implements BeanRegistrationAotProcessor {
+
+	@Nullable
+	@Override
+	public BeanRegistrationAotContribution processAheadOfTime(RegisteredBean registeredBean) {
+
+		if (isAuditingHandler(registeredBean)) {
+			return (generationContext, beanRegistrationCode) -> new AuditingHints.AuditingRuntimeHints()
+					.registerHints(generationContext.getRuntimeHints(), registeredBean.getBeanFactory().getBeanClassLoader());
+		}
+		if (ReactiveWrappers.isAvailable(ReactiveLibrary.PROJECT_REACTOR) && isReactiveAuditorAware(registeredBean)) {
+			return (generationContext, beanRegistrationCode) -> new AuditingHints.ReactiveAuditingRuntimeHints()
+					.registerHints(generationContext.getRuntimeHints(), registeredBean.getBeanFactory().getBeanClassLoader());
+		}
+		return null;
+	}
+
+	boolean isAuditingHandler(RegisteredBean bean) {
+		return ClassUtils.isAssignable(AuditorAware.class, bean.getBeanClass());
+	}
+
+	boolean isReactiveAuditorAware(RegisteredBean bean) {
+		return ClassUtils.isAssignable(ReactiveAuditorAware.class, bean.getBeanClass());
+	}
+}

src/main/resources/META-INF/spring/aot.factories

@@ -2,3 +2,5 @@ org.springframework.beans.factory.aot.BeanFactoryInitializationAotProcessor=\
 	org.springframework.data.aot.SpringDataBeanFactoryInitializationAotProcessor
 org.springframework.aot.hint.RuntimeHintsRegistrar=\
 	org.springframework.data.aot.hint.RepositoryRuntimeHints
+org.springframework.beans.factory.aot.BeanRegistrationAotProcessor=\
+    org.springframework.data.aot.AuditingBeanRegistrationAotProcessor

src/test/java/org/springframework/data/aot/AuditingBeanRegistrationAotProcessorUnitTests.java

@@ -0,0 +1,107 @@
+/*
+ * Copyright 2022 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.aot;
+
+import static org.assertj.core.api.Assertions.*;
+import static org.springframework.data.aot.BeanRegistrationContributionAssert.*;
+
+import reactor.core.publisher.Mono;
+
+import java.util.Optional;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.aot.BeanRegistrationAotContribution;
+import org.springframework.beans.factory.support.BeanDefinitionBuilder;
+import org.springframework.beans.factory.support.DefaultListableBeanFactory;
+import org.springframework.beans.factory.support.RegisteredBean;
+import org.springframework.data.domain.AuditorAware;
+import org.springframework.data.domain.ReactiveAuditorAware;
+
+/**
+ * @author Christoph Strobl
+ */
+class AuditingBeanRegistrationAotProcessorUnitTests {
+
+	DefaultListableBeanFactory beanFactory;
+
+	@BeforeEach
+	void beforeEach() {
+		beanFactory = new DefaultListableBeanFactory();
+	}
+
+	@Test // GH-2593
+	void contributesProxyForAuditorAwareInterface() {
+
+		String beanName = "auditorAware";
+		beanFactory.registerBeanDefinition("auditorAware",
+				BeanDefinitionBuilder.rootBeanDefinition(MyAuditorAware.class).getBeanDefinition());
+
+		BeanRegistrationAotContribution beanRegistrationAotContribution = new AuditingBeanRegistrationAotProcessor()
+				.processAheadOfTime(RegisteredBean.of(beanFactory, beanName));
+		assertThatAotContribution(beanRegistrationAotContribution).codeContributionSatisfies(code -> {
+			code.contributesJdkProxyFor(AuditorAware.class);
+		});
+	}
+
+	@Test // GH-2593
+	void contributesProxyForReactriveAuditorAwareInterface() {
+
+		String beanName = "auditorAware";
+		beanFactory.registerBeanDefinition("auditorAware",
+				BeanDefinitionBuilder.rootBeanDefinition(MyReactiveAuditorAware.class).getBeanDefinition());
+
+		BeanRegistrationAotContribution beanRegistrationAotContribution = new AuditingBeanRegistrationAotProcessor()
+				.processAheadOfTime(RegisteredBean.of(beanFactory, beanName));
+		assertThatAotContribution(beanRegistrationAotContribution).codeContributionSatisfies(code -> {
+			code.contributesJdkProxyFor(ReactiveAuditorAware.class);
+		});
+	}
+
+	@Test // GH-2593
+	void ignoresNonAuditorAware() {
+
+		String beanName = "auditorAware";
+		beanFactory.registerBeanDefinition("auditorAware",
+				BeanDefinitionBuilder.rootBeanDefinition(Nothing.class).getBeanDefinition());
+
+		BeanRegistrationAotContribution beanRegistrationAotContribution = new AuditingBeanRegistrationAotProcessor()
+				.processAheadOfTime(RegisteredBean.of(beanFactory, beanName));
+		assertThat(beanRegistrationAotContribution).isNull();
+	}
+
+	static class Nothing {
+		public Optional getCurrentAuditor() {
+			return Optional.empty();
+		}
+	}
+
+	static class MyAuditorAware implements AuditorAware {
+
+		@Override
+		public Optional getCurrentAuditor() {
+			return Optional.empty();
+		}
+	}
+
+	static class MyReactiveAuditorAware implements ReactiveAuditorAware {
+
+		@Override
+		public Mono getCurrentAuditor() {
+			return null;
+		}
+	}
+}

src/test/java/org/springframework/data/aot/BeanRegistrationContributionAssert.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2022 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.aot;
+
+import static org.mockito.Mockito.*;
+
+import java.util.function.Consumer;
+
+import org.assertj.core.api.AbstractAssert;
+import org.springframework.aot.generate.ClassNameGenerator;
+import org.springframework.aot.generate.DefaultGenerationContext;
+import org.springframework.aot.generate.InMemoryGeneratedFiles;
+import org.springframework.beans.factory.aot.BeanRegistrationAotContribution;
+import org.springframework.beans.factory.aot.BeanRegistrationCode;
+
+/**
+ * @author Christoph Strobl
+ */
+public class BeanRegistrationContributionAssert extends AbstractAssert<BeanRegistrationContributionAssert, BeanRegistrationAotContribution> {
+
+	protected BeanRegistrationContributionAssert(BeanRegistrationAotContribution beanRegistrationAotContribution) {
+		super(beanRegistrationAotContribution, BeanRegistrationContributionAssert.class);
+	}
+
+	public static BeanRegistrationContributionAssert assertThatAotContribution(BeanRegistrationAotContribution actual) {
+		return new BeanRegistrationContributionAssert(actual);
+	}
+	public BeanRegistrationContributionAssert codeContributionSatisfies(
+			Consumer<CodeContributionAssert> assertWith) {
+
+		BeanRegistrationCode mockBeanRegistrationCode = mock(BeanRegistrationCode.class);
+
+		DefaultGenerationContext generationContext = new DefaultGenerationContext(new ClassNameGenerator(Object.class),
+				new InMemoryGeneratedFiles());
+
+		this.actual.applyTo(generationContext, mockBeanRegistrationCode);
+
+		assertWith.accept(new CodeContributionAssert(generationContext));
+
+		return this;
+	}
+}