Add property to prevent observations starting with a prefix

For example, setting management.observations.enable.denied.prefix=false
will prevent all observations starting with 'denied.prefix'

Closes gh-34802

Author: mhalbritter

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

@@ -40,7 +40,6 @@
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingClass;
-import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -79,14 +78,8 @@ ObservationRegistry observationRegistry() {
 
 	@Bean
 	@Order(0)
-	PropertiesObservationFilter propertiesObservationFilter(ObservationProperties properties) {
-		return new PropertiesObservationFilter(properties);
-	}
-
-	@Bean
-	@ConditionalOnProperty(name = "management.observations.spring-security.enabled", havingValue = "false")
-	ObservationPredicate springSecurityObservationsDisabler() {
-		return (name, context) -> !name.startsWith("spring.security.");
+	PropertiesObservationFilterPredicate propertiesObservationFilter(ObservationProperties properties) {
+		return new PropertiesObservationFilterPredicate(properties);
 	}
 
 	@Configuration(proxyBeanMethods = false)

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

@@ -27,6 +27,7 @@
  * observations.
  *
  * @author Brian Clozel
+ * @author Moritz Halbritter
  * @since 3.0.0
  */
 @ConfigurationProperties("management.observations")
@@ -39,6 +40,20 @@ public class ObservationProperties {
 	 */
 	private Map<String, String> keyValues = new LinkedHashMap<>();
 
+	/**
+	 * Whether observations starting with the specified name should be enabled. The
+	 * longest match wins, the key 'all' can also be used to configure all observations.
+	 */
+	private Map<String, Boolean> enable = new LinkedHashMap<>();
+
+	public Map<String, Boolean> getEnable() {
+		return this.enable;
+	}
+
+	public void setEnable(Map<String, Boolean> enable) {
+		this.enable = enable;
+	}
+
 	public Http getHttp() {
 		return this.http;
 	}

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

@@ -0,0 +1,83 @@
+/*
+ * Copyright 2012-2023 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.observation;
+
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.function.Supplier;
+
+import io.micrometer.common.KeyValues;
+import io.micrometer.observation.Observation.Context;
+import io.micrometer.observation.ObservationFilter;
+import io.micrometer.observation.ObservationPredicate;
+
+import org.springframework.util.StringUtils;
+
+/**
+ * {@link ObservationFilter} to apply settings from {@link ObservationProperties}.
+ *
+ * @author Moritz Halbritter
+ */
+class PropertiesObservationFilterPredicate implements ObservationFilter, ObservationPredicate {
+
+	private final ObservationFilter commonKeyValuesFilter;
+
+	private final ObservationProperties properties;
+
+	PropertiesObservationFilterPredicate(ObservationProperties properties) {
+		this.properties = properties;
+		this.commonKeyValuesFilter = createCommonKeyValuesFilter(properties);
+	}
+
+	@Override
+	public Context map(Context context) {
+		return this.commonKeyValuesFilter.map(context);
+	}
+
+	@Override
+	public boolean test(String name, Context context) {
+		return lookupWithFallbackToAll(this.properties.getEnable(), name, true);
+	}
+
+	private static <T> T lookupWithFallbackToAll(Map<String, T> values, String name, T defaultValue) {
+		if (values.isEmpty()) {
+			return defaultValue;
+		}
+		return doLookup(values, name, () -> values.getOrDefault("all", defaultValue));
+	}
+
+	private static <T> T doLookup(Map<String, T> values, String name, Supplier<T> defaultValue) {
+		while (StringUtils.hasLength(name)) {
+			T result = values.get(name);
+			if (result != null) {
+				return result;
+			}
+			int lastDot = name.lastIndexOf('.');
+			name = (lastDot != -1) ? name.substring(0, lastDot) : "";
+		}
+		return defaultValue.get();
+	}
+
+	private static ObservationFilter createCommonKeyValuesFilter(ObservationProperties properties) {
+		if (properties.getKeyValues().isEmpty()) {
+			return (context) -> context;
+		}
+		KeyValues keyValues = KeyValues.of(properties.getKeyValues().entrySet(), Entry::getKey, Entry::getValue);
+		return (context) -> context.addLowCardinalityKeyValues(keyValues);
+	}
+
+}

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

@@ -2038,12 +2038,6 @@
         "level": "error"
       }
     },
-    {
-      "name": "management.observations.spring-security.enabled",
-      "description": "Whether to enable observations for Spring Security",
-      "type": "java.lang.Boolean",
-      "defaultValue": true
-    },
     {
       "name": "management.otlp.tracing.compression",
       "defaultValue": "none"

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

@@ -191,7 +191,8 @@ void autoConfiguresObservationFilters() {
 
 	@Test
 	void shouldSupplyPropertiesObservationFilterBean() {
-		this.contextRunner.run((context) -> assertThat(context).hasSingleBean(PropertiesObservationFilter.class));
+		this.contextRunner
+			.run((context) -> assertThat(context).hasSingleBean(PropertiesObservationFilterPredicate.class));
 	}
 
 	@Test
@@ -303,14 +304,13 @@ void shouldNotDisableSpringSecurityObservationsByDefault() {
 
 	@Test
 	void shouldDisableSpringSecurityObservationsIfPropertyIsSet() {
-		this.contextRunner.withPropertyValues("management.observations.spring-security.enabled=false")
-			.run((context) -> {
-				ObservationRegistry observationRegistry = context.getBean(ObservationRegistry.class);
-				Observation.start("spring.security.filterchains", observationRegistry).stop();
-				MeterRegistry meterRegistry = context.getBean(MeterRegistry.class);
-				assertThatThrownBy(() -> meterRegistry.get("spring.security.filterchains").timer())
-					.isInstanceOf(MeterNotFoundException.class);
-			});
+		this.contextRunner.withPropertyValues("management.observations.enable.spring.security=false").run((context) -> {
+			ObservationRegistry observationRegistry = context.getBean(ObservationRegistry.class);
+			Observation.start("spring.security.filterchains", observationRegistry).stop();
+			MeterRegistry meterRegistry = context.getBean(MeterRegistry.class);
+			assertThatThrownBy(() -> meterRegistry.get("spring.security.filterchains").timer())
+				.isInstanceOf(MeterNotFoundException.class);
+		});
 	}
 
 	@Configuration(proxyBeanMethods = false)

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/observation/ObservationAutoConfigurationTests.java

@@ -0,0 +1,100 @@
+/*
+ * Copyright 2012-2023 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.observation;
+
+import io.micrometer.common.KeyValue;
+import io.micrometer.common.KeyValues;
+import io.micrometer.observation.Observation.Context;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link PropertiesObservationFilterPredicate}.
+ *
+ * @author Moritz Halbritter
+ */
+class PropertiesObservationFilterPredicateTests {
+
+	@Test
+	void shouldDoNothingIfKeyValuesAreEmpty() {
+		PropertiesObservationFilterPredicate filter = createFilter();
+		Context mapped = mapContext(filter, "a", "alpha");
+		assertThat(mapped.getLowCardinalityKeyValues()).containsExactly(KeyValue.of("a", "alpha"));
+	}
+
+	@Test
+	void shouldAddKeyValues() {
+		PropertiesObservationFilterPredicate filter = createFilter("b", "beta");
+		Context mapped = mapContext(filter, "a", "alpha");
+		assertThat(mapped.getLowCardinalityKeyValues()).containsExactly(KeyValue.of("a", "alpha"),
+				KeyValue.of("b", "beta"));
+	}
+
+	@Test
+	void shouldFilter() {
+		PropertiesObservationFilterPredicate predicate = createPredicate("spring.security");
+		Context context = new Context();
+		assertThat(predicate.test("spring.security.filterchains", context)).isFalse();
+		assertThat(predicate.test("spring.security", context)).isFalse();
+		assertThat(predicate.test("spring.data", context)).isTrue();
+		assertThat(predicate.test("spring", context)).isTrue();
+	}
+
+	@Test
+	void filterShouldFallbackToAll() {
+		PropertiesObservationFilterPredicate predicate = createPredicate("all");
+		Context context = new Context();
+		assertThat(predicate.test("spring.security.filterchains", context)).isFalse();
+		assertThat(predicate.test("spring.security", context)).isFalse();
+		assertThat(predicate.test("spring.data", context)).isFalse();
+		assertThat(predicate.test("spring", context)).isFalse();
+	}
+
+	@Test
+	void shouldNotFilterIfDisabledNamesIsEmpty() {
+		PropertiesObservationFilterPredicate predicate = createPredicate();
+		Context context = new Context();
+		assertThat(predicate.test("spring.security.filterchains", context)).isTrue();
+		assertThat(predicate.test("spring.security", context)).isTrue();
+		assertThat(predicate.test("spring.data", context)).isTrue();
+		assertThat(predicate.test("spring", context)).isTrue();
+	}
+
+	private static Context mapContext(PropertiesObservationFilterPredicate filter, String... initialKeyValues) {
+		Context context = new Context();
+		context.addLowCardinalityKeyValues(KeyValues.of(initialKeyValues));
+		return filter.map(context);
+	}
+
+	private static PropertiesObservationFilterPredicate createFilter(String... keyValues) {
+		ObservationProperties properties = new ObservationProperties();
+		for (int i = 0; i < keyValues.length; i += 2) {
+			properties.getKeyValues().put(keyValues[i], keyValues[i + 1]);
+		}
+		return new PropertiesObservationFilterPredicate(properties);
+	}
+
+	private static PropertiesObservationFilterPredicate createPredicate(String... disabledNames) {
+		ObservationProperties properties = new ObservationProperties();
+		for (String name : disabledNames) {
+			properties.getEnable().put(name, false);
+		}
+		return new PropertiesObservationFilterPredicate(properties);
+	}
+
+}