GH-212 - Invert default for event republication to false.

This is to accommodate cluster setups and avoid multiple instances from resubmitting outstanding event publications concurrently.

Author: odrotbohm

spring-modulith-events/spring-modulith-events-core/src/main/java/org/springframework/modulith/events/support/PersistentApplicationEventMulticaster.java

@@ -15,7 +15,6 @@
  */
 package org.springframework.modulith.events.support;
 
-import java.lang.reflect.Field;
 import java.util.Collection;
 import java.util.List;
 import java.util.function.Consumer;
@@ -30,7 +29,6 @@
 import org.springframework.context.PayloadApplicationEvent;
 import org.springframework.context.event.AbstractApplicationEventMulticaster;
 import org.springframework.context.event.ApplicationEventMulticaster;
-import org.springframework.context.event.ApplicationListenerMethodAdapter;
 import org.springframework.core.ResolvableType;
 import org.springframework.core.annotation.AnnotationAwareOrderComparator;
 import org.springframework.core.env.Environment;
@@ -118,7 +116,7 @@ public void multicastEvent(ApplicationEvent event, ResolvableType eventType) {
 	@Override
 	public void afterSingletonsInstantiated() {
 
-		if (Boolean.FALSE.equals(environment.get().getProperty(REPUBLISH_ON_RESTART, Boolean.class))) {
+		if (!Boolean.TRUE.equals(environment.get().getProperty(REPUBLISH_ON_RESTART, Boolean.class))) {
 			return;
 		}
 

spring-modulith-events/spring-modulith-events-core/src/main/resources/META-INF/spring-configuration-metadata.json

@@ -10,7 +10,7 @@
 			"name": "spring.modulith.republish-outstanding-events-on-restart",
 			"type": "java.lang.boolean",
 			"description": "Whether to republish outstanding event publications on restarts of the application.",
-			"defaultValue": "true"
+			"defaultValue": "false"
 		}
 	]
 }

spring-modulith-events/spring-modulith-events-core/src/test/java/org/springframework/modulith/events/support/PersistentApplicationEventMulticasterUnitTests.java

@@ -42,21 +42,21 @@ void setUp() {
 		this.multicaster = new PersistentApplicationEventMulticaster(() -> registry, () -> environment);
 	}
 
-	@Test // GH-240
-	void doesNotRepublishEventsOnRestartIfExplicitlyDisabled() {
-
-		var source = new MapPropertySource("test",
-				Map.of(PersistentApplicationEventMulticaster.REPUBLISH_ON_RESTART, "false"));
-		environment.getPropertySources().addFirst(source);
+	@Test // GH-240, GH-251
+	void doesNotRepublishEventsOnRestartByDefault() {
 
 		multicaster.afterSingletonsInstantiated();
 
 		verify(registry, never()).findIncompletePublications();
 	}
 
-	@Test // GH-240
+	@Test // GH-240, GH-251
 	void triggersRepublicationIfExplicitlyEnabled() {
 
+		var source = new MapPropertySource("test",
+				Map.of(PersistentApplicationEventMulticaster.REPUBLISH_ON_RESTART, "true"));
+		environment.getPropertySources().addFirst(source);
+
 		multicaster.afterSingletonsInstantiated();
 
 		verify(registry).findIncompletePublications();

spring-modulith-events/spring-modulith-events-tests/src/test/java/example/events/PersistentDomainEventIntegrationTest.java

@@ -20,12 +20,15 @@
 import lombok.Getter;
 import lombok.RequiredArgsConstructor;
 
+import java.util.Map;
+
 import org.junit.jupiter.api.Test;
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.event.EventListener;
+import org.springframework.core.env.MapPropertySource;
 import org.springframework.modulith.events.EventPublication;
 import org.springframework.modulith.events.EventPublicationRegistry;
 import org.springframework.modulith.events.PublicationTargetIdentifier;
@@ -45,6 +48,8 @@ class PersistentDomainEventIntegrationTest {
 	void exposesEventPublicationForFailedListener() throws Exception {
 
 		AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+		context.getEnvironment().getPropertySources().addFirst(
+				new MapPropertySource("test", Map.of("spring.modulith.republish-outstanding-events-on-restart", "true")));
 		context.register(ApplicationConfiguration.class, InfrastructureConfiguration.class);
 		context.refresh();