Merge pull request #42472 from mmoayyed

* pr/42472:
  Polish 'Allow common messages to be specified for message sources'
  Allow common messages to be specified for message sources

Closes gh-42472

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/context/MessageSourceAutoConfiguration.java

@@ -16,7 +16,11 @@
 
 package org.springframework.boot.autoconfigure.context;
 
+import java.io.IOException;
+import java.io.UncheckedIOException;
 import java.time.Duration;
+import java.util.List;
+import java.util.Properties;
 
 import org.springframework.aot.hint.RuntimeHints;
 import org.springframework.aot.hint.RuntimeHintsRegistrar;
@@ -38,9 +42,11 @@ import org.springframework.context.annotation.Conditional;
 import org.springframework.context.annotation.ImportRuntimeHints;
 import org.springframework.context.support.AbstractApplicationContext;
 import org.springframework.context.support.ResourceBundleMessageSource;
+import org.springframework.core.CollectionFactory;
 import org.springframework.core.Ordered;
 import org.springframework.core.io.Resource;
 import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
+import org.springframework.core.io.support.PropertiesLoaderUtils;
 import org.springframework.core.type.AnnotatedTypeMetadata;
 import org.springframework.util.CollectionUtils;
 import org.springframework.util.ConcurrentReferenceHashMap;
@@ -81,9 +87,26 @@ public class MessageSourceAutoConfiguration {
 		}
 		messageSource.setAlwaysUseMessageFormat(properties.isAlwaysUseMessageFormat());
 		messageSource.setUseCodeAsDefaultMessage(properties.isUseCodeAsDefaultMessage());
+		messageSource.setCommonMessages(loadCommonMessages(properties.getCommonMessages()));
 		return messageSource;
 	}
 
+	private Properties loadCommonMessages(List<Resource> resources) {
+		if (CollectionUtils.isEmpty(resources)) {
+			return null;
+		}
+		Properties properties = CollectionFactory.createSortedProperties(false);
+		for (Resource resource : resources) {
+			try {
+				PropertiesLoaderUtils.fillProperties(properties, resource);
+			}
+			catch (IOException ex) {
+				throw new UncheckedIOException("Failed to load common messages from '%s'".formatted(resource), ex);
+			}
+		}
+		return properties;
+	}
+
 	protected static class ResourceBundleCondition extends SpringBootCondition {
 
 		private static final ConcurrentReferenceHashMap<String, ConditionOutcome> cache = new ConcurrentReferenceHashMap<>();

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/context/MessageSourceProperties.java

@@ -25,6 +25,7 @@ import java.util.List;
 
 import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.boot.convert.DurationUnit;
+import org.springframework.core.io.Resource;
 
 /**
  * Configuration properties for Message Source.
@@ -44,6 +45,11 @@ public class MessageSourceProperties {
 	 */
 	private List<String> basename = new ArrayList<>(List.of("messages"));
 
+	/**
+	 * List of locale-independent property file resources containing common messages.
+	 */
+	private List<Resource> commonMessages;
+
 	/**
 	 * Message bundles encoding.
 	 */
@@ -123,4 +129,12 @@ public class MessageSourceProperties {
 		this.useCodeAsDefaultMessage = useCodeAsDefaultMessage;
 	}
 
+	public List<Resource> getCommonMessages() {
+		return this.commonMessages;
+	}
+
+	public void setCommonMessages(List<Resource> commonMessages) {
+		this.commonMessages = commonMessages;
+	}
+
 }

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/context/MessageSourceAutoConfigurationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -58,7 +58,7 @@ class MessageSourceAutoConfigurationTests {
 
 	@Test
 	void propertiesBundleWithSlashIsDetected() {
-		this.contextRunner.withPropertyValues("spring.messages.basename:test/messages").run((context) -> {
+		this.contextRunner.withPropertyValues("spring.messages.basename=test/messages").run((context) -> {
 			assertThat(context).hasSingleBean(MessageSource.class);
 			assertThat(context.getMessage("foo", null, "Foo message", Locale.UK)).isEqualTo("bar");
 		});
@@ -66,7 +66,7 @@ class MessageSourceAutoConfigurationTests {
 
 	@Test
 	void propertiesBundleWithDotIsDetected() {
-		this.contextRunner.withPropertyValues("spring.messages.basename:test.messages").run((context) -> {
+		this.contextRunner.withPropertyValues("spring.messages.basename=test.messages").run((context) -> {
 			assertThat(context).hasSingleBean(MessageSource.class);
 			assertThat(context.getMessage("foo", null, "Foo message", Locale.UK)).isEqualTo("bar");
 		});
@@ -74,7 +74,7 @@ class MessageSourceAutoConfigurationTests {
 
 	@Test
 	void testEncodingWorks() {
-		this.contextRunner.withPropertyValues("spring.messages.basename:test/swedish")
+		this.contextRunner.withPropertyValues("spring.messages.basename=test/swedish")
 			.run((context) -> assertThat(context.getMessage("foo", null, "Foo message", Locale.UK))
 				.isEqualTo("Some text with some swedish öäå!"));
 	}
@@ -82,14 +82,14 @@ class MessageSourceAutoConfigurationTests {
 	@Test
 	void testCacheDurationNoUnit() {
 		this.contextRunner
-			.withPropertyValues("spring.messages.basename:test/messages", "spring.messages.cache-duration=10")
+			.withPropertyValues("spring.messages.basename=test/messages", "spring.messages.cache-duration=10")
 			.run(assertCache(10 * 1000));
 	}
 
 	@Test
 	void testCacheDurationWithUnit() {
 		this.contextRunner
-			.withPropertyValues("spring.messages.basename:test/messages", "spring.messages.cache-duration=1m")
+			.withPropertyValues("spring.messages.basename=test/messages", "spring.messages.cache-duration=1m")
 			.run(assertCache(60 * 1000));
 	}
 
@@ -102,7 +102,7 @@ class MessageSourceAutoConfigurationTests {
 
 	@Test
 	void testMultipleMessageSourceCreated() {
-		this.contextRunner.withPropertyValues("spring.messages.basename:test/messages,test/messages2")
+		this.contextRunner.withPropertyValues("spring.messages.basename=test/messages,test/messages2")
 			.run((context) -> {
 				assertThat(context.getMessage("foo", null, "Foo message", Locale.UK)).isEqualTo("bar");
 				assertThat(context.getMessage("foo-foo", null, "Foo-Foo message", Locale.UK)).isEqualTo("bar-bar");
@@ -116,9 +116,27 @@ class MessageSourceAutoConfigurationTests {
 			.run((context) -> assertThat(context.getMessage("foo", null, "Foo message", Locale.UK)).isEqualTo("bar"));
 	}
 
+	@Test
+	void testCommonMessages() {
+		this.contextRunner
+			.withPropertyValues("spring.messages.basename=test/messages",
+					"spring.messages.common-messages=classpath:test/common-messages.properties")
+			.run((context) -> assertThat(context.getMessage("hello", null, "Hello!", Locale.UK)).isEqualTo("world"));
+	}
+
+	@Test
+	void testCommonMessagesWhenNotFound() {
+		this.contextRunner
+			.withPropertyValues("spring.messages.basename=test/messages",
+					"spring.messages.common-messages=classpath:test/common-messages-missing.properties")
+			.run((context) -> assertThat(context).getFailure()
+				.hasMessageContaining(
+						"Failed to load common messages from 'class path resource [test/common-messages-missing.properties]'"));
+	}
+
 	@Test
 	void testFallbackDefault() {
-		this.contextRunner.withPropertyValues("spring.messages.basename:test/messages")
+		this.contextRunner.withPropertyValues("spring.messages.basename=test/messages")
 			.run((context) -> assertThat(context.getBean(MessageSource.class))
 				.hasFieldOrPropertyWithValue("fallbackToSystemLocale", true));
 	}
@@ -126,7 +144,7 @@ class MessageSourceAutoConfigurationTests {
 	@Test
 	void testFallbackTurnOff() {
 		this.contextRunner
-			.withPropertyValues("spring.messages.basename:test/messages",
+			.withPropertyValues("spring.messages.basename=test/messages",
 					"spring.messages.fallback-to-system-locale:false")
 			.run((context) -> assertThat(context.getBean(MessageSource.class))
 				.hasFieldOrPropertyWithValue("fallbackToSystemLocale", false));
@@ -134,7 +152,7 @@ class MessageSourceAutoConfigurationTests {
 
 	@Test
 	void testFormatMessageDefault() {
-		this.contextRunner.withPropertyValues("spring.messages.basename:test/messages")
+		this.contextRunner.withPropertyValues("spring.messages.basename=test/messages")
 			.run((context) -> assertThat(context.getBean(MessageSource.class))
 				.hasFieldOrPropertyWithValue("alwaysUseMessageFormat", false));
 	}
@@ -142,7 +160,7 @@ class MessageSourceAutoConfigurationTests {
 	@Test
 	void testFormatMessageOn() {
 		this.contextRunner
-			.withPropertyValues("spring.messages.basename:test/messages",
+			.withPropertyValues("spring.messages.basename=test/messages",
 					"spring.messages.always-use-message-format:true")
 			.run((context) -> assertThat(context.getBean(MessageSource.class))
 				.hasFieldOrPropertyWithValue("alwaysUseMessageFormat", true));
@@ -150,7 +168,7 @@ class MessageSourceAutoConfigurationTests {
 
 	@Test
 	void testUseCodeAsDefaultMessageDefault() {
-		this.contextRunner.withPropertyValues("spring.messages.basename:test/messages")
+		this.contextRunner.withPropertyValues("spring.messages.basename=test/messages")
 			.run((context) -> assertThat(context.getBean(MessageSource.class))
 				.hasFieldOrPropertyWithValue("useCodeAsDefaultMessage", false));
 	}
@@ -158,8 +176,8 @@ class MessageSourceAutoConfigurationTests {
 	@Test
 	void testUseCodeAsDefaultMessageOn() {
 		this.contextRunner
-			.withPropertyValues("spring.messages.basename:test/messages",
-					"spring.messages.use-code-as-default-message:true")
+			.withPropertyValues("spring.messages.basename=test/messages",
+					"spring.messages.use-code-as-default-message=true")
 			.run((context) -> assertThat(context.getBean(MessageSource.class))
 				.hasFieldOrPropertyWithValue("useCodeAsDefaultMessage", true));
 	}
@@ -173,13 +191,13 @@ class MessageSourceAutoConfigurationTests {
 	@Test
 	void existingMessageSourceInParentIsIgnored() {
 		this.contextRunner.run((parent) -> this.contextRunner.withParent(parent)
-			.withPropertyValues("spring.messages.basename:test/messages")
+			.withPropertyValues("spring.messages.basename=test/messages")
 			.run((context) -> assertThat(context.getMessage("foo", null, "Foo message", Locale.UK)).isEqualTo("bar")));
 	}
 
 	@Test
 	void messageSourceWithNonStandardBeanNameIsIgnored() {
-		this.contextRunner.withPropertyValues("spring.messages.basename:test/messages")
+		this.contextRunner.withPropertyValues("spring.messages.basename=test/messages")
 			.withUserConfiguration(CustomBeanNameMessageSourceConfiguration.class)
 			.run((context) -> assertThat(context.getMessage("foo", null, Locale.US)).isEqualTo("bar"));
 	}

spring-boot-project/spring-boot-autoconfigure/src/test/resources/test/common-messages.properties

@@ -0,0 +1 @@
+hello=world

spring-boot-project/spring-boot-docs/src/docs/antora/modules/reference/pages/features/internationalization.adoc

@@ -14,10 +14,12 @@ The basename of the resource bundle as well as several other attributes can be c
 ----
 spring:
   messages:
-    basename: "messages,config.i18n.messages"
+    basename: "messages, config.i18n.messages"
+    common-messages: "classpath:my-common-messages.properties"
     fallback-to-system-locale: false
 ----
 
-TIP: `spring.messages.basename` supports comma-separated list of locations, either a package qualifier or a resource resolved from the classpath root.
+TIP: The configprop:spring.messages.basename[] property supports a list of locations, either a package qualifier or a resource resolved from the classpath root.
+The configprop:spring.messages.common-messages[] property supports a list of property file resources.
 
 See javadoc:org.springframework.boot.autoconfigure.context.MessageSourceProperties[] for more supported options.