Disable the java info contributor by default

Closes gh-28310

Co-authored-by Phillip Webb <pwebb@vmware.com>

Author: wilkinsona

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/OnEndpointElementCondition.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2021 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.
@@ -54,7 +54,7 @@ public ConditionOutcome getMatchOutcome(ConditionContext context, AnnotatedTypeM
 		if (outcome != null) {
 			return outcome;
 		}
-		return getDefaultEndpointsOutcome(context);
+		return getDefaultOutcome(context, annotationAttributes);
 	}
 
 	protected ConditionOutcome getEndpointOutcome(ConditionContext context, String endpointName) {
@@ -68,6 +68,27 @@ protected ConditionOutcome getEndpointOutcome(ConditionContext context, String e
 		return null;
 	}
 
+	/**
+	 * Return the default outcome that should be used if not property is set. By default
+	 * this method will use the {@code <prefix>.defaults.enabled} property, matching if it
+	 * is {@code true} or if it is not configured.
+	 * @param context the condition context
+	 * @param annotationAttributes the annotation attributes
+	 * @return the default outcome
+	 * @since 2.6.0
+	 */
+	protected ConditionOutcome getDefaultOutcome(ConditionContext context, AnnotationAttributes annotationAttributes) {
+		return getDefaultEndpointsOutcome(context);
+	}
+
+	/**
+	 * Return the default outcome that should be used.
+	 * @param context the condition context
+	 * @return the default outcome
+	 * @deprecated since 2.6.0 for removal in 2.8.0 in favor of
+	 * {@link #getDefaultOutcome(ConditionContext, AnnotationAttributes)}
+	 */
+	@Deprecated
 	protected ConditionOutcome getDefaultEndpointsOutcome(ConditionContext context) {
 		boolean match = Boolean
 				.parseBoolean(context.getEnvironment().getProperty(this.prefix + "defaults.enabled", "true"));

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/info/ConditionalOnEnabledInfoContributor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2021 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.
@@ -25,11 +25,9 @@
 import org.springframework.context.annotation.Conditional;
 
 /**
- * {@link Conditional @Conditional} that checks whether or not a default info contributor
- * is enabled. Matches if the value of the {@code management.info.<name>.enabled} property
- * is {@code true}. Otherwise, matches if the value of the
- * {@code management.info.defaults.enabled} property is {@code true} or if it is not
- * configured.
+ * {@link Conditional @Conditional} that checks whether or not an info contributor is
+ * enabled. Matches if the value of the {@code management.info.<name>.enabled} property is
+ * {@code true}. Otherwise, use the specific {@link #fallback() fallback} method.
  *
  * @author Stephane Nicoll
  * @since 2.0.0
@@ -46,4 +44,10 @@
 	 */
 	String value();
 
+	/**
+	 * Fallback behavior when {@code management.info.<name>.enabled} has not been set.
+	 * @return the fallback behavior
+	 */
+	InfoContributorFallback fallback() default InfoContributorFallback.USE_DEFAULTS_PROPERTY;
+
 }

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/info/InfoContributorAutoConfiguration.java

@@ -80,7 +80,7 @@ public InfoContributor buildInfoContributor(BuildProperties buildProperties) {
 	}
 
 	@Bean
-	@ConditionalOnEnabledInfoContributor("java")
+	@ConditionalOnEnabledInfoContributor(value = "java", fallback = InfoContributorFallback.DISABLE)
 	@Order(DEFAULT_ORDER)
 	public JavaInfoContributor javaInfoContributor() {
 		return new JavaInfoContributor();

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/info/InfoContributorFallback.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2012-2021 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.boot.actuate.autoconfigure.info;
+
+import org.springframework.boot.actuate.autoconfigure.OnEndpointElementCondition;
+
+/**
+ * Controls the fallback behavior when the primary property that controls whether an info
+ * contributor is enabled is not set.
+ *
+ * @author Andy Wilkinson
+ * @since 2.6.0
+ * @see OnEndpointElementCondition
+ */
+public enum InfoContributorFallback {
+
+	/**
+	 * Fall back to the {@code management.info.defaults.enabled} property, matching if it
+	 * is {@code true} or if it is not configured.
+	 */
+	USE_DEFAULTS_PROPERTY,
+
+	/**
+	 * Do not fall back, thereby disabling the info contributor.
+	 */
+	DISABLE;
+
+}

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/info/OnEnabledInfoContributorCondition.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2021 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.
@@ -17,7 +17,11 @@
 package org.springframework.boot.actuate.autoconfigure.info;
 
 import org.springframework.boot.actuate.autoconfigure.OnEndpointElementCondition;
+import org.springframework.boot.autoconfigure.condition.ConditionMessage;
+import org.springframework.boot.autoconfigure.condition.ConditionOutcome;
 import org.springframework.context.annotation.Condition;
+import org.springframework.context.annotation.ConditionContext;
+import org.springframework.core.annotation.AnnotationAttributes;
 
 /**
  * {@link Condition} that checks if an info indicator is enabled.
@@ -30,4 +34,14 @@ class OnEnabledInfoContributorCondition extends OnEndpointElementCondition {
 		super("management.info.", ConditionalOnEnabledInfoContributor.class);
 	}
 
+	@Override
+	protected ConditionOutcome getDefaultOutcome(ConditionContext context, AnnotationAttributes annotationAttributes) {
+		InfoContributorFallback fallback = annotationAttributes.getEnum("fallback");
+		if (fallback == InfoContributorFallback.DISABLE) {
+			return new ConditionOutcome(false, ConditionMessage.forCondition(ConditionalOnEnabledInfoContributor.class)
+					.because("management.info." + annotationAttributes.getString("value") + ".enabled is not true"));
+		}
+		return super.getDefaultOutcome(context, annotationAttributes);
+	}
+
 }

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -273,6 +273,12 @@
       "name": "management.info.git.mode",
       "defaultValue": "simple"
     },
+    {
+      "name": "management.info.java.enabled",
+      "type": "java.lang.Boolean",
+      "description": "Whether to enable Java info.",
+      "defaultValue": false
+    },
     {
       "name": "management.metrics.binders.files.enabled",
       "type": "java.lang.Boolean",

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/info/InfoContributorAutoConfigurationTests.java

@@ -54,18 +54,11 @@ void disableEnvContributor() {
 				.run((context) -> assertThat(context).doesNotHaveBean(EnvironmentInfoContributor.class));
 	}
 
-	@Test
-	void disableJavaContributor() {
-		this.contextRunner.withPropertyValues("management.info.java.enabled=false")
-				.run((context) -> assertThat(context).doesNotHaveBean(JavaInfoContributor.class));
-	}
-
 	@Test
 	void defaultInfoContributorsEnabled() {
 		this.contextRunner.run((context) -> {
-			assertThat(context).hasSingleBean(EnvironmentInfoContributor.class)
-					.hasSingleBean(JavaInfoContributor.class);
-			assertThat(context.getBeansOfType(InfoContributor.class)).hasSize(2);
+			assertThat(context).hasSingleBean(EnvironmentInfoContributor.class);
+			assertThat(context.getBeansOfType(InfoContributor.class)).hasSize(1);
 		});
 	}
 
@@ -146,7 +139,7 @@ void customBuildInfoContributor() {
 
 	@Test
 	void javaInfoContributor() {
-		this.contextRunner.run((context) -> {
+		this.contextRunner.withPropertyValues("management.info.java.enabled=true").run((context) -> {
 			assertThat(context).hasSingleBean(JavaInfoContributor.class);
 			Map<String, Object> content = invokeContributor(context.getBean(JavaInfoContributor.class));
 			assertThat(content).containsKey("java");

spring-boot-project/spring-boot-docs/src/docs/asciidoc/actuator/endpoints.adoc

@@ -1145,24 +1145,41 @@ Spring Boot includes a number of auto-configured `InfoContributor` beans, and yo
 ==== Auto-configured InfoContributors
 When appropriate, Spring auto-configures the following `InfoContributor` beans:
 
-[cols="1,4"]
+[cols="1,4,8,4"]
 |===
-| Name | Description
+| ID | Name | Description | Prequisites
+
+| `build`
+| {spring-boot-actuator-module-code}/info/BuildInfoContributor.java[`BuildInfoContributor`]
+| Exposes build information.
+| A `META-INF/build-info.properties` resource.
 
+| `env`
 | {spring-boot-actuator-module-code}/info/EnvironmentInfoContributor.java[`EnvironmentInfoContributor`]
-| Exposes any key from the `Environment` under the `info` key.
+| Exposes any property from the `Environment` whose name starts with `info.`.
+| None.
 
+| `git`
 | {spring-boot-actuator-module-code}/info/GitInfoContributor.java[`GitInfoContributor`]
-| Exposes git information if a `git.properties` file is available.
-
-| {spring-boot-actuator-module-code}/info/BuildInfoContributor.java[`BuildInfoContributor`]
-| Exposes build information if a `META-INF/build-info.properties` file is available.
+| Exposes git information.
+| A `git.properties` resource.
 
+| `java`
 | {spring-boot-actuator-module-code}/info/JavaInfoContributor.java[`JavaInfoContributor`]
-| Exposes Java runtime information under the `java` key.
+| Exposes Java runtime information.
+| None.
+
 |===
 
-TIP: You can disable them all by setting the configprop:management.info.defaults.enabled[] property.
+Whether or not an individual contributor is enabled is controlled by its `management.info.<id>.enabled` property.
+Different contributors have different defaults for this property, depending on their prerequisites and the nature of the information that they expose.
+
+With no prequisites to indicate that it should be enabled, the `java` contributor is disabled by default.
+You can enable it by setting the configprop:management.info.java.enabled[] property to `true`.
+
+The `env`, `git`, and `build` info contributors are enabled by default.
+Each can be disabled by setting its `management.info.<id>.enabled` property to `false`.
+Alternatively, to disable every contributor that is usually enabled by default, set the configprop:management.info.defaults.enabled[] property to `false`.