Startup metrics for per module repository scanning.

This commit adds application startup metrics for the time taken to scan the context for Spring Data repositories on a per module (JPA, MongoDB,...) base.
We capture the module name, the scan base package and the number of repositories found.

{
  "startupStep": {
    "name": "spring.data.repository.scanning",
    "id": ...,
    "parentId": ...,
    "tags": [
      {
        "key": "data-module",
        "value": "MongoDB"
      },
      {
        "key": "packages",
        "value": "com.example.demo"
      },
      {
        "key": "repository.count",
        "value": "1"
      }
    ]
  }
}

Author: christophstrobl

src/main/java/org/springframework/data/repository/config/RepositoryConfigurationDelegate.java

@@ -25,7 +25,7 @@
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-
+import org.springframework.beans.factory.config.ConfigurableBeanFactory;
 import org.springframework.beans.factory.config.DependencyDescriptor;
 import org.springframework.beans.factory.parsing.BeanComponentDefinition;
 import org.springframework.beans.factory.support.AbstractBeanDefinition;
@@ -34,12 +34,15 @@
 import org.springframework.beans.factory.support.BeanDefinitionRegistry;
 import org.springframework.beans.factory.support.DefaultListableBeanFactory;
 import org.springframework.context.annotation.ContextAnnotationAutowireCandidateResolver;
+import org.springframework.context.support.GenericApplicationContext;
 import org.springframework.core.env.Environment;
 import org.springframework.core.env.EnvironmentCapable;
 import org.springframework.core.env.StandardEnvironment;
 import org.springframework.core.io.ResourceLoader;
 import org.springframework.core.io.support.SpringFactoriesLoader;
 import org.springframework.core.log.LogMessage;
+import org.springframework.core.metrics.ApplicationStartup;
+import org.springframework.core.metrics.StartupStep;
 import org.springframework.data.repository.core.support.RepositoryFactorySupport;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
@@ -143,6 +146,11 @@ public List<BeanComponentDefinition> registerRepositoriesIn(BeanDefinitionRegist
 					configurationSource.getBasePackages().stream().collect(Collectors.joining(", "))));
 		}
 
+		ApplicationStartup startup = getStartup(registry);
+		StartupStep repoScan = startup.start("spring.data.repository.scanning");
+		repoScan.tag("data-module", extension.getModuleName());
+		repoScan.tag("packages", configurationSource.getBasePackages().stream().collect(Collectors.joining(", ")));
+
 		watch.start();
 
 		Collection<RepositoryConfiguration<RepositoryConfigurationSource>> configurations = extension
@@ -184,6 +192,9 @@ public List<BeanComponentDefinition> registerRepositoriesIn(BeanDefinitionRegist
 
 		watch.stop();
 
+		repoScan.tag("repository.count", Integer.toString(configurations.size()));
+		repoScan.end();
+
 		if (logger.isInfoEnabled()) {
 			logger.info(LogMessage.format("Finished Spring Data repository scanning in %s ms. Found %s %s repository interfaces.", //
 					watch.getLastTaskTimeMillis(), configurations.size(), extension.getModuleName()));
@@ -208,7 +219,6 @@ private static void potentiallyLazifyRepositories(Map<String, RepositoryConfigur
 		}
 
 		DefaultListableBeanFactory beanFactory = DefaultListableBeanFactory.class.cast(registry);
-
 		AutowireCandidateResolver resolver = beanFactory.getAutowireCandidateResolver();
 
 		if (!Arrays.asList(ContextAnnotationAutowireCandidateResolver.class, LazyRepositoryInjectionPointResolver.class)
@@ -253,6 +263,23 @@ private boolean multipleStoresDetected() {
 		return multipleModulesFound;
 	}
 
+	ApplicationStartup getStartup(BeanDefinitionRegistry registry) {
+
+		if(ConfigurableBeanFactory.class.isInstance(registry)) {
+			return ((ConfigurableBeanFactory)registry).getApplicationStartup();
+		}
+
+		if (DefaultListableBeanFactory.class.isInstance(registry)) {
+			return ((DefaultListableBeanFactory)registry).getBeanProvider(ApplicationStartup.class).getIfAvailable(() -> ApplicationStartup.DEFAULT);
+		}
+
+		if(GenericApplicationContext.class.isInstance(registry)) {
+			return ((GenericApplicationContext)registry).getDefaultListableBeanFactory().getApplicationStartup();
+		}
+
+		return ApplicationStartup.DEFAULT;
+	}
+
 	/**
 	 * Customer {@link ContextAnnotationAutowireCandidateResolver} that also considers all injection points for lazy
 	 * repositories lazy.

src/test/java/org/springframework/data/repository/config/RepositoryConfigurationDelegateUnitTests.java

@@ -20,6 +20,7 @@
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
+import org.mockito.Mockito;
 import org.mockito.junit.jupiter.MockitoExtension;
 import org.mockito.junit.jupiter.MockitoSettings;
 import org.mockito.quality.Strictness;
@@ -35,6 +36,8 @@
 import org.springframework.context.annotation.FilterType;
 import org.springframework.context.support.GenericApplicationContext;
 import org.springframework.core.env.StandardEnvironment;
+import org.springframework.core.metrics.ApplicationStartup;
+import org.springframework.core.metrics.StartupStep;
 import org.springframework.core.type.StandardAnnotationMetadata;
 import org.springframework.data.repository.config.RepositoryConfigurationDelegate.LazyRepositoryInjectionPointResolver;
 import org.springframework.data.repository.sample.AddressRepository;
@@ -107,6 +110,26 @@ private static ListableBeanFactory assertLazyRepositoryBeanSetup(Class<?> config
 		return context.getDefaultListableBeanFactory();
 	}
 
+	@Test // DATACMNS-1832
+	void writesRepositoryScanningMetrics() {
+
+		ApplicationStartup startup = Mockito.spy(ApplicationStartup.DEFAULT);
+
+		StandardEnvironment environment = new StandardEnvironment();
+		GenericApplicationContext context = new GenericApplicationContext();
+		context.setApplicationStartup(startup);
+
+		RepositoryConfigurationSource configSource = new AnnotationRepositoryConfigurationSource(
+				new StandardAnnotationMetadata(TestConfig.class, true), EnableRepositories.class, context, environment,
+				context.getDefaultListableBeanFactory());
+
+		RepositoryConfigurationDelegate delegate = new RepositoryConfigurationDelegate(configSource, context, environment);
+
+		delegate.registerRepositoriesIn(context, extension);
+
+		Mockito.verify(startup).start("spring.data.repository.scanning");
+	}
+
 	@EnableRepositories(basePackageClasses = ProductRepository.class)
 	static class TestConfig {}