Improve extension of Neo4jHealthIndicator

This commit makes it easier to extend `Neo4jHealthIndicator` for cases
where a custom cypher needs to be executed.

Closes gh-11120

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/neo4j/Neo4jHealthIndicatorAutoConfigurationTests.java

@@ -17,29 +17,33 @@
 package org.springframework.boot.actuate.autoconfigure.neo4j;
 
 import org.junit.Test;
+import org.neo4j.ogm.session.Session;
 import org.neo4j.ogm.session.SessionFactory;
 
 import org.springframework.boot.actuate.autoconfigure.health.HealthIndicatorAutoConfiguration;
 import org.springframework.boot.actuate.health.ApplicationHealthIndicator;
+import org.springframework.boot.actuate.health.Health;
 import org.springframework.boot.actuate.neo4j.Neo4jHealthIndicator;
 import org.springframework.boot.autoconfigure.AutoConfigurations;
-import org.springframework.boot.autoconfigure.AutoConfigureBefore;
 import org.springframework.boot.test.context.runner.ApplicationContextRunner;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.entry;
 import static org.mockito.Mockito.mock;
 
 /**
  * Tests for {@link Neo4jHealthIndicatorAutoConfiguration}.
  *
  * @author Phillip Webb
+ * @author Stephane Nicoll
  */
 public class Neo4jHealthIndicatorAutoConfigurationTests {
 
 	private ApplicationContextRunner contextRunner = new ApplicationContextRunner()
-			.withConfiguration(AutoConfigurations.of(Neo4jConfiguration.class,
+			.withUserConfiguration(Neo4jConfiguration.class)
+			.withConfiguration(AutoConfigurations.of(
 					Neo4jHealthIndicatorAutoConfiguration.class,
 					HealthIndicatorAutoConfiguration.class));
 
@@ -58,8 +62,19 @@ public class Neo4jHealthIndicatorAutoConfigurationTests {
 						.hasSingleBean(ApplicationHealthIndicator.class));
 	}
 
+	@Test
+	public void defaultIndicatorCanBeReplaced() {
+		this.contextRunner
+				.withUserConfiguration(CustomIndicatorConfiguration.class).run(
+				(context) -> {
+					assertThat(context).hasSingleBean(Neo4jHealthIndicator.class);
+					assertThat(context).doesNotHaveBean(ApplicationHealthIndicator.class);
+					Health health = context.getBean(Neo4jHealthIndicator.class).health();
+					assertThat(health.getDetails()).containsOnly(entry("test", true));
+				});
+	}
+
 	@Configuration
-	@AutoConfigureBefore(Neo4jHealthIndicatorAutoConfiguration.class)
 	protected static class Neo4jConfiguration {
 
 		@Bean
@@ -69,4 +84,18 @@ public class Neo4jHealthIndicatorAutoConfigurationTests {
 
 	}
 
+	@Configuration
+	protected static class CustomIndicatorConfiguration {
+
+		@Bean
+		public Neo4jHealthIndicator neo4jHealthIndicator(SessionFactory sessionFactory) {
+			return new Neo4jHealthIndicator(sessionFactory) {
+				@Override
+				protected void extractResult(Session session, Health.Builder builder) {
+					builder.up().withDetail("test", true);
+				}
+			};
+		}
+	}
+
 }

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/neo4j/Neo4jHealthIndicator.java

@@ -55,6 +55,16 @@ public class Neo4jHealthIndicator extends AbstractHealthIndicator {
 	@Override
 	protected void doHealthCheck(Health.Builder builder) throws Exception {
 		Session session = this.sessionFactory.openSession();
+		extractResult(session, builder);
+	}
+
+	/**
+	 * Provide health details using the specified {@link Session} and
+	 * {@link Health.Builder Builder}.
+	 * @param session the session to use to execute a cypher statement
+	 * @param builder the builder to add details to
+	 */
+	protected void extractResult(Session session, Health.Builder builder) {
 		Result result = session.query(CYPHER, Collections.emptyMap());
 		builder.up().withDetail("nodes",
 				result.queryResults().iterator().next().get("nodes"));