Merge pull request #45 from ryantenney/register

Register metrics and metrics sets in xml

pom.xml

@@ -77,6 +77,12 @@
 			<artifactId>metrics-annotation</artifactId>
 			<version>${metrics.version}</version>
 		</dependency>
+		<dependency>
+			<groupId>com.codahale.metrics</groupId>
+			<artifactId>metrics-jvm</artifactId>
+			<version>${metrics.version}</version>
+			<optional>true</optional>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework</groupId>
 			<artifactId>spring-core</artifactId>

src/main/java/com/ryantenney/metrics/spring/config/MetricsNamespaceHandler.java

@@ -19,12 +19,15 @@
 
 class MetricsNamespaceHandler extends NamespaceHandlerSupport {
 
+	public static final String METRICS_NAMESPACE = "http://www.ryantenney.com/schema/metrics";
+
 	@Override
 	public void init() {
 		registerBeanDefinitionParser("annotation-driven", new AnnotationDrivenBeanDefinitionParser());
 		registerBeanDefinitionParser("metric-registry", new MetricRegistryBeanDefinitionParser());
 		registerBeanDefinitionParser("health-check-registry", new HealthCheckRegistryBeanDefinitionParser());
 		registerBeanDefinitionParser("reporter", new ReporterBeanDefinitionParser());
+		registerBeanDefinitionParser("register", new RegisterMetricBeanDefinitionParser());
 	}
 
 }

src/main/java/com/ryantenney/metrics/spring/config/RegisterMetricBeanDefinitionParser.java

@@ -0,0 +1,103 @@
+/**
+ * Copyright (C) 2012 Ryan W Tenney ([email protected])
+ *
+ * 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 com.ryantenney.metrics.spring.config;
+
+import java.util.List;
+
+import org.springframework.beans.factory.InitializingBean;
+import org.springframework.beans.factory.config.BeanDefinition;
+import org.springframework.beans.factory.config.ConstructorArgumentValues;
+import org.springframework.beans.factory.config.RuntimeBeanReference;
+import org.springframework.beans.factory.parsing.BeanComponentDefinition;
+import org.springframework.beans.factory.parsing.CompositeComponentDefinition;
+import org.springframework.beans.factory.support.RootBeanDefinition;
+import org.springframework.beans.factory.xml.BeanDefinitionParser;
+import org.springframework.beans.factory.xml.ParserContext;
+import org.springframework.util.StringUtils;
+import org.springframework.util.xml.DomUtils;
+import org.w3c.dom.Element;
+
+import com.codahale.metrics.Metric;
+import com.codahale.metrics.MetricRegistry;
+import com.codahale.metrics.MetricSet;
+
+import static com.ryantenney.metrics.spring.config.MetricsNamespaceHandler.METRICS_NAMESPACE;
+
+class RegisterMetricBeanDefinitionParser implements BeanDefinitionParser {
+
+	@Override
+	public BeanDefinition parse(Element element, ParserContext parserContext) {
+		final CompositeComponentDefinition compDefinition = new CompositeComponentDefinition(element.getTagName(), parserContext.extractSource(element));
+		parserContext.pushContainingComponent(compDefinition);
+
+		final String metricRegistryBeanName = element.getAttribute("metric-registry");
+		if (!StringUtils.hasText(metricRegistryBeanName)) {
+			throw new RuntimeException(); // TODO
+		}
+		final RuntimeBeanReference metricRegistryBeanRef = new RuntimeBeanReference(metricRegistryBeanName);
+
+		final List<Element> metricElements = DomUtils.getChildElementsByTagName(element, new String[] { "bean", "ref" });
+		for (Element metricElement : metricElements) {
+			// Get the name attribute and remove it (to prevent Spring from looking for a BeanDefinitionDecorator)
+			final String name = metricElement.getAttributeNS(METRICS_NAMESPACE, "name");
+			if (name != null) {
+				metricElement.removeAttributeNS(METRICS_NAMESPACE, "name");
+			}
+
+			final Object metric = parserContext.getDelegate().parsePropertySubElement(metricElement, null);
+
+			final RootBeanDefinition metricRegistererDef = new RootBeanDefinition(MetricRegisterer.class);
+			metricRegistererDef.setSource(parserContext.extractSource(metricElement));
+			metricRegistererDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
+
+			final ConstructorArgumentValues args = metricRegistererDef.getConstructorArgumentValues();
+			args.addIndexedArgumentValue(0, metricRegistryBeanRef);
+			args.addIndexedArgumentValue(1, name);
+			args.addIndexedArgumentValue(2, metric);
+
+			final String beanName = parserContext.getReaderContext().registerWithGeneratedName(metricRegistererDef);
+			parserContext.registerComponent(new BeanComponentDefinition(metricRegistererDef, beanName));
+		}
+
+		parserContext.popAndRegisterContainingComponent();
+
+		return null;
+	}
+
+	public static class MetricRegisterer implements InitializingBean {
+
+		private final MetricRegistry metricRegistry;
+		private final String name;
+		private final Metric metric;
+
+		public MetricRegisterer(MetricRegistry metricRegistry, String name, Metric metric) {
+			this.metricRegistry = metricRegistry;
+			this.name = name;
+			this.metric = metric;
+
+			if (!StringUtils.hasText(name) && !(metric instanceof MetricSet)) {
+				throw new RuntimeException(); // TODO
+			}
+		}
+
+		@Override
+		public void afterPropertiesSet() throws Exception {
+			metricRegistry.register(name, metric);
+		}
+
+	}
+
+}

src/main/resources/com/ryantenney/metrics/spring/config/metrics-3.0.xsd

@@ -22,7 +22,7 @@
 			targetNamespace="http://www.ryantenney.com/schema/metrics"
 			elementFormDefault="qualified" attributeFormDefault="unqualified">
 
-	<xsd:import namespace="http://www.springframework.org/schema/beans"/>
+	<xsd:import namespace="http://www.springframework.org/schema/beans" schemaLocation="http://www.springframework.org/schema/beans/spring-beans-3.2.xsd"/>
 
 	<xsd:element name="annotation-driven">
 		<xsd:complexType>
@@ -55,4 +55,15 @@
 		</xsd:complexType>
 	</xsd:element>
 
+	<xsd:element name="register">
+		<xsd:complexType>
+			<xsd:sequence maxOccurs="unbounded">
+				<xsd:element ref="beans:bean"/>
+			</xsd:sequence>
+			<xsd:attribute name="metric-registry" type="xsd:string" use="required"/>
+		</xsd:complexType>
+	</xsd:element>
+
+	<xsd:attribute name="name" type="xsd:string"/>
+
 </xsd:schema>

src/test/java/com/ryantenney/metrics/spring/RegisterElementTest.java

@@ -0,0 +1,44 @@
+/**
+ * Copyright (C) 2012 Ryan W Tenney ([email protected])
+ *
+ * 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 com.ryantenney.metrics.spring;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.springframework.context.support.ClassPathXmlApplicationContext;
+
+import com.codahale.metrics.MetricRegistry;
+
+public class RegisterElementTest {
+
+	@Test
+	public void testRegisterMetrics() {
+		ClassPathXmlApplicationContext ctx = null;
+		try {
+			ctx = new ClassPathXmlApplicationContext("classpath:register-element-test.xml");
+			MetricRegistry registry = ctx.getBean(MetricRegistry.class);
+			Assert.assertTrue(registry.getMetrics().size() > 0);
+			for (String metricName : registry.getMetrics().keySet()) {
+				Assert.assertTrue(metricName.startsWith("jvm."));
+			}
+		}
+		finally {
+			if (ctx != null) {
+				ctx.close();
+			}
+		}
+	}
+
+}

src/test/resources/register-element-test.xml

@@ -0,0 +1,39 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+
+    Copyright (C) 2012 Ryan W Tenney ([email protected])
+
+    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.
+
+-->
+<beans xmlns="http://www.springframework.org/schema/beans"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xmlns:c="http://www.springframework.org/schema/c"
+	xmlns:context="http://www.springframework.org/schema/context"
+	xmlns:metrics="http://www.ryantenney.com/schema/metrics"
+
+	xsi:schemaLocation="
+			http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
+			http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd
+			http://www.ryantenney.com/schema/metrics http://www.ryantenney.com/schema/metrics/metrics-3.0.xsd">
+
+	<metrics:metric-registry id="metrics" />
+
+	<metrics:register metric-registry="metrics">
+		<bean metrics:name="jvm.gc" class="com.codahale.metrics.jvm.GarbageCollectorMetricSet" />
+		<bean metrics:name="jvm.memory" class="com.codahale.metrics.jvm.MemoryUsageGaugeSet" />
+		<bean metrics:name="jvm.thread-states" class="com.codahale.metrics.jvm.ThreadStatesGaugeSet" />
+		<bean metrics:name="jvm.fd.usage" class="com.codahale.metrics.jvm.FileDescriptorRatioGauge" />
+	</metrics:register>
+
+</beans>