Add support MeterFilter#maximumAllowableTags for WebFlux and WebMvc

closes gh-13913.

Author: nosan

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

@@ -137,6 +137,13 @@ public static class Server {
 			 */
 			private String requestsMetricName = "http.server.requests";
 
+			/**
+			 * Maximum number of unique URI tag values allowed. After the max number of
+			 * tag values is reached, metrics with additional tag values are denied by
+			 * filter.
+			 */
+			private int maxUriTags = 100;
+
 			public boolean isAutoTimeRequests() {
 				return this.autoTimeRequests;
 			}
@@ -153,6 +160,14 @@ public void setRequestsMetricName(String requestsMetricName) {
 				this.requestsMetricName = requestsMetricName;
 			}
 
+			public int getMaxUriTags() {
+				return this.maxUriTags;
+			}
+
+			public void setMaxUriTags(int maxUriTags) {
+				this.maxUriTags = maxUriTags;
+			}
+
 		}
 
 	}

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

@@ -0,0 +1,59 @@
+/*
+ * Copyright 2012-2018 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
+ *
+ *      http://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.metrics;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.function.Supplier;
+
+import io.micrometer.core.instrument.Meter;
+import io.micrometer.core.instrument.config.MeterFilter;
+import io.micrometer.core.instrument.config.MeterFilterReply;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import org.springframework.util.Assert;
+
+/**
+ * {@link MeterFilter} to log only once a warning message and deny {@link Meter.Id}.
+ *
+ * @author Dmytro Nosan
+ * @since 2.0.5
+ */
+public final class OnlyOnceLoggingDenyMeterFilter implements MeterFilter {
+
+	private final Logger logger = LoggerFactory
+			.getLogger(OnlyOnceLoggingDenyMeterFilter.class);
+
+	private final AtomicBoolean alreadyWarned = new AtomicBoolean(false);
+
+	private final Supplier<String> message;
+
+	public OnlyOnceLoggingDenyMeterFilter(Supplier<String> message) {
+		Assert.notNull(message, "Message must not be null");
+		this.message = message;
+	}
+
+	@Override
+	public MeterFilterReply accept(Meter.Id id) {
+		if (this.logger.isWarnEnabled()
+				&& this.alreadyWarned.compareAndSet(false, true)) {
+			this.logger.warn(this.message.get());
+		}
+		return MeterFilterReply.DENY;
+	}
+
+}

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/metrics/web/client/RestTemplateMetricsAutoConfiguration.java

@@ -16,17 +16,12 @@
 
 package org.springframework.boot.actuate.autoconfigure.metrics.web.client;
 
-import java.util.concurrent.atomic.AtomicBoolean;
-
-import io.micrometer.core.instrument.Meter.Id;
 import io.micrometer.core.instrument.MeterRegistry;
 import io.micrometer.core.instrument.config.MeterFilter;
-import io.micrometer.core.instrument.config.MeterFilterReply;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 import org.springframework.boot.actuate.autoconfigure.metrics.MetricsAutoConfiguration;
 import org.springframework.boot.actuate.autoconfigure.metrics.MetricsProperties;
+import org.springframework.boot.actuate.autoconfigure.metrics.OnlyOnceLoggingDenyMeterFilter;
 import org.springframework.boot.actuate.autoconfigure.metrics.export.simple.SimpleMetricsExportAutoConfiguration;
 import org.springframework.boot.actuate.metrics.web.client.DefaultRestTemplateExchangeTagsProvider;
 import org.springframework.boot.actuate.metrics.web.client.MetricsRestTemplateCustomizer;
@@ -76,43 +71,12 @@ public MetricsRestTemplateCustomizer metricsRestTemplateCustomizer(
 	@Order(0)
 	public MeterFilter metricsHttpClientUriTagFilter(MetricsProperties properties) {
 		String metricName = properties.getWeb().getClient().getRequestsMetricName();
-		MeterFilter denyFilter = new MaximumUriTagsReachedMeterFilter(metricName);
+		MeterFilter denyFilter = new OnlyOnceLoggingDenyMeterFilter(() -> String.format(
+				"Reached the maximum number of URI tags for '%s'. "
+						+ "Are you using uriVariables on RestTemplate calls?",
+				metricName));
 		return MeterFilter.maximumAllowableTags(metricName, "uri",
 				properties.getWeb().getClient().getMaxUriTags(), denyFilter);
 	}
 
-	/**
-	 * {@link MeterFilter} to deny further URI tags and log a warning.
-	 */
-	private static class MaximumUriTagsReachedMeterFilter implements MeterFilter {
-
-		private final Logger logger = LoggerFactory
-				.getLogger(MaximumUriTagsReachedMeterFilter.class);
-
-		private final String metricName;
-
-		private final AtomicBoolean alreadyWarned = new AtomicBoolean(false);
-
-		MaximumUriTagsReachedMeterFilter(String metricName) {
-			this.metricName = metricName;
-		}
-
-		@Override
-		public MeterFilterReply accept(Id id) {
-			if (this.alreadyWarned.compareAndSet(false, true)) {
-				logWarning();
-			}
-			return MeterFilterReply.DENY;
-		}
-
-		private void logWarning() {
-			if (this.logger.isWarnEnabled()) {
-				this.logger.warn(
-						"Reached the maximum number of URI tags for '" + this.metricName
-								+ "'. Are you using uriVariables on HTTP client calls?");
-			}
-		}
-
-	}
-
 }

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/metrics/web/reactive/WebFluxMetricsAutoConfiguration.java

@@ -17,9 +17,11 @@
 package org.springframework.boot.actuate.autoconfigure.metrics.web.reactive;
 
 import io.micrometer.core.instrument.MeterRegistry;
+import io.micrometer.core.instrument.config.MeterFilter;
 
 import org.springframework.boot.actuate.autoconfigure.metrics.MetricsAutoConfiguration;
 import org.springframework.boot.actuate.autoconfigure.metrics.MetricsProperties;
+import org.springframework.boot.actuate.autoconfigure.metrics.OnlyOnceLoggingDenyMeterFilter;
 import org.springframework.boot.actuate.autoconfigure.metrics.export.simple.SimpleMetricsExportAutoConfiguration;
 import org.springframework.boot.actuate.metrics.web.reactive.server.DefaultWebFluxTagsProvider;
 import org.springframework.boot.actuate.metrics.web.reactive.server.MetricsWebFilter;
@@ -31,12 +33,14 @@
 import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.core.annotation.Order;
 
 /**
  * {@link EnableAutoConfiguration Auto-configuration} for instrumentation of Spring
  * WebFlux applications.
  *
  * @author Jon Schneider
+ * @author Dmytro Nosan
  * @since 2.0.0
  */
 @Configuration
@@ -59,4 +63,14 @@ public MetricsWebFilter webfluxMetrics(MeterRegistry registry,
 				properties.getWeb().getServer().getRequestsMetricName());
 	}
 
+	@Bean
+	@Order(0)
+	public MeterFilter metricsHttpServerUriTagFilter(MetricsProperties properties) {
+		String metricName = properties.getWeb().getServer().getRequestsMetricName();
+		MeterFilter filter = new OnlyOnceLoggingDenyMeterFilter(() -> String
+				.format("Reached the maximum number of URI tags for '%s'.", metricName));
+		return MeterFilter.maximumAllowableTags(metricName, "uri",
+				properties.getWeb().getServer().getMaxUriTags(), filter);
+	}
+
 }

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/metrics/web/servlet/WebMvcMetricsAutoConfiguration.java

@@ -19,10 +19,12 @@
 import javax.servlet.DispatcherType;
 
 import io.micrometer.core.instrument.MeterRegistry;
+import io.micrometer.core.instrument.config.MeterFilter;
 
 import org.springframework.boot.actuate.autoconfigure.metrics.MetricsAutoConfiguration;
 import org.springframework.boot.actuate.autoconfigure.metrics.MetricsProperties;
 import org.springframework.boot.actuate.autoconfigure.metrics.MetricsProperties.Web.Server;
+import org.springframework.boot.actuate.autoconfigure.metrics.OnlyOnceLoggingDenyMeterFilter;
 import org.springframework.boot.actuate.autoconfigure.metrics.export.simple.SimpleMetricsExportAutoConfiguration;
 import org.springframework.boot.actuate.metrics.web.servlet.DefaultWebMvcTagsProvider;
 import org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter;
@@ -38,6 +40,7 @@
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.Ordered;
+import org.springframework.core.annotation.Order;
 import org.springframework.web.context.WebApplicationContext;
 import org.springframework.web.servlet.DispatcherServlet;
 
@@ -46,6 +49,7 @@
  * MVC servlet-based request mappings.
  *
  * @author Jon Schneider
+ * @author Dmytro Nosan
  * @since 2.0.0
  */
 @Configuration
@@ -78,4 +82,14 @@ public FilterRegistrationBean<WebMvcMetricsFilter> webMvcMetricsFilter(
 		return registration;
 	}
 
+	@Bean
+	@Order(0)
+	public MeterFilter metricsHttpServerUriTagFilter(MetricsProperties properties) {
+		String metricName = properties.getWeb().getServer().getRequestsMetricName();
+		MeterFilter filter = new OnlyOnceLoggingDenyMeterFilter(() -> String
+				.format("Reached the maximum number of URI tags for '%s'.", metricName));
+		return MeterFilter.maximumAllowableTags(metricName, "uri",
+				properties.getWeb().getServer().getMaxUriTags(), filter);
+	}
+
 }

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/metrics/web/client/RestTemplateMetricsAutoConfigurationTests.java

@@ -97,7 +97,7 @@ public void afterMaxUrisReachedFurtherUrisAreDenied() {
 							.hasSize(maxUriTags);
 					assertThat(this.out.toString())
 							.contains("Reached the maximum number of URI tags "
-									+ "for 'http.client.requests'");
+									+ "for 'http.client.requests'. Are you using uriVariables on RestTemplate calls?");
 				});
 	}
 

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/metrics/web/reactive/WebFluxMetricsAutoConfigurationTests.java

@@ -16,17 +16,26 @@
 
 package org.springframework.boot.actuate.autoconfigure.metrics.web.reactive;
 
+import io.micrometer.core.instrument.MeterRegistry;
+import org.junit.Rule;
 import org.junit.Test;
+import reactor.core.publisher.Mono;
 
 import org.springframework.boot.actuate.autoconfigure.metrics.MetricsAutoConfiguration;
 import org.springframework.boot.actuate.autoconfigure.metrics.export.simple.SimpleMetricsExportAutoConfiguration;
 import org.springframework.boot.actuate.metrics.web.reactive.server.DefaultWebFluxTagsProvider;
 import org.springframework.boot.actuate.metrics.web.reactive.server.MetricsWebFilter;
 import org.springframework.boot.actuate.metrics.web.reactive.server.WebFluxTagsProvider;
 import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.autoconfigure.web.reactive.WebFluxAutoConfiguration;
 import org.springframework.boot.test.context.runner.ReactiveWebApplicationContextRunner;
+import org.springframework.boot.test.context.runner.WebApplicationContextRunner;
+import org.springframework.boot.test.rule.OutputCapture;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.test.web.reactive.server.WebTestClient;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.mockito.Mockito.mock;
@@ -35,6 +44,7 @@
  * Tests for {@link WebFluxMetricsAutoConfiguration}
  *
  * @author Brian Clozel
+ * @author Dmytro Nosan
  */
 public class WebFluxMetricsAutoConfigurationTests {
 
@@ -43,6 +53,18 @@ public class WebFluxMetricsAutoConfigurationTests {
 					SimpleMetricsExportAutoConfiguration.class,
 					WebFluxMetricsAutoConfiguration.class));
 
+	@Rule
+	public OutputCapture output = new OutputCapture();
+
+	@Test
+	public void backsOffWhenMeterRegistryIsMissing() {
+		new WebApplicationContextRunner()
+				.withConfiguration(
+						AutoConfigurations.of(WebFluxMetricsAutoConfiguration.class))
+				.run((context) -> assertThat(context)
+						.doesNotHaveBean(WebFluxMetricsAutoConfiguration.class));
+	}
+
 	@Test
 	public void shouldProvideWebFluxMetricsBeans() {
 		this.contextRunner.run((context) -> {
@@ -58,6 +80,28 @@ public void shouldNotOverrideCustomTagsProvider() {
 						.hasSize(1).containsKey("customWebFluxTagsProvider"));
 	}
 
+	@Test
+	public void afterMaxUrisReachedFurtherUrisAreDenied() {
+		this.contextRunner
+				.withConfiguration(AutoConfigurations.of(WebFluxAutoConfiguration.class))
+				.withUserConfiguration(TestController.class)
+				.withPropertyValues("management.metrics.web.server.max-uri-tags=2")
+				.run((context) -> {
+					WebTestClient webTestClient = WebTestClient
+							.bindToApplicationContext(context).build();
+
+					for (int i = 0; i < 3; i++) {
+						webTestClient.get().uri("/test" + i).exchange().expectStatus()
+								.isOk();
+					}
+					MeterRegistry registry = context.getBean(MeterRegistry.class);
+					assertThat(registry.get("http.server.requests").meters()).hasSize(2);
+					assertThat(this.output.toString())
+							.contains("Reached the maximum number of URI tags "
+									+ "for 'http.server.requests'");
+				});
+	}
+
 	@Configuration
 	protected static class CustomWebFluxTagsProviderConfig {
 
@@ -68,4 +112,24 @@ public WebFluxTagsProvider customWebFluxTagsProvider() {
 
 	}
 
+	@RestController
+	static class TestController {
+
+		@GetMapping("test0")
+		public Mono<String> test0() {
+			return Mono.just("test0");
+		}
+
+		@GetMapping("test1")
+		public Mono<String> test1() {
+			return Mono.just("test1");
+		}
+
+		@GetMapping("test2")
+		public Mono<String> test2() {
+			return Mono.just("test2");
+		}
+
+	}
+
 }