##About
The metrics-spring
module integrates Coda Hale's Metrics library with Spring, and provides XML and Java configuration.
This module does the following things:
- Creates metrics and proxies beans which contain methods annotated with
@Timed
,@Metered
,@ExceptionMetered
, and@Counted
- Registers a
Gauge
for beans which have members annotated with@Gauge
and@CachedGauge
- Autowires Timers, Meters, Counters and Histograms into fields annotated with
@Metric
- Registers with the
HealthCheckRegistry
any beans which extend the classHealthCheck
- Creates reporters from XML config and binds them to the Spring lifecycle
- Registers metrics and metric sets in XML
###Maven
Current version is 3.0.1, which is compatible with Metrics 3.0
<dependency>
<groupId>com.ryantenney.metrics</groupId>
<artifactId>metrics-spring</artifactId>
<version>3.0.1</version>
</dependency>
This module was formerly contained in the Metrics repository.
###Basic Usage
As of version 3, metrics-spring
may be configured using XML or Java, depending on your personal preference.
Spring Context XML:
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
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.ryantenney.com/schema/metrics
http://www.ryantenney.com/schema/metrics/metrics-3.0.xsd">
<!-- Registry should be defined in only one context XML file -->
<metrics:metric-registry id="metrics" />
<!-- annotation-driven must be included in all context files -->
<metrics:annotation-driven metric-registry="metrics" />
<!-- (Optional) Registry should be defined in only one context XML file -->
<metrics:reporter type="console" metric-registry="metrics" period="1m" />
<!-- (Optional) The metrics in this example require the metrics-jvm jar-->
<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 and other Spring config -->
</beans>
Java Annotation Config:
import java.util.concurrent.TimeUnit;
import org.springframework.context.annotation.Configuration;
import com.codahale.metrics.ConsoleReporter;
import com.codahale.metrics.MetricRegistry;
import com.codahale.metrics.SharedMetricRegistries;
import com.ryantenney.metrics.spring.config.annotation.EnableMetrics;
import com.ryantenney.metrics.spring.config.annotation.MetricsConfigurerAdapter;
@Configuration
@EnableMetrics
public class SpringConfiguringClass extends MetricsConfigurerAdapter {
@Override
public void configureReporters(MetricRegistry metricRegistry) {
ConsoleReporter
.forRegistry(metricRegistry)
.build()
.start(1, TimeUnit.MINUTES);
}
}
###XML Config Documentation
The <metrics:annotation-driven />
element is required, and has 4 optional arguments:
- Attributes
metric-registry
- the id of theMetricRegsitry
bean with which the generated metrics should be registered. If omitted a newMetricRegistry
bean is created.health-check-registry
- the id of theHealthCheckRegsitry
bean with which to register any beans which extend the classHealthCheck
. If omitted a newHealthCheckRegistry
bean is created.proxy-target-class
- if set to true, always creates CGLIB proxies instead of defaulting to JDK proxies. This may be necessary if you use class-based autowiring.expose-proxy
- if set to true, the target can access the proxy which wraps it by callingAopContext.currentProxy()
.
The <metrics:metric-registry />
element constructs a new MetricRegistry or retrieves a shared registry:
- Attributes
id
- the bean name with which to register the MetricRegistry beanname
- the name of the MetricRegistry, if present, this calls SharedMetricRegistries.getOrCreate(name)
The <metrics:health-check-registry />
element constructs a new HealthCheckRegistry:
- Attributes
id
- the bean name with which to register the HealthCheckRegistry bean
The <metrics:reporter />
element creates and starts a reporter:
- Attributes
id
- the bean namemetric-registry
- the id of theMetricRegsitry
bean for which the reporter should retrieve metricstype
- the type of the reporter. Additional types may be registered through SPI (more on this later).console
: ConsoleReporterjmx
: JmxReporterslf4j
: Slf4jReporterganglia
: GangliaReporter (requiresmetrics-ganglia
)graphite
: GraphiteReporter (requiresmetrics-graphite
)
The <metrics:register />
element registers with the MetricRegistry a bean which extends implements Metric or MetricSet
- Attributes
metric-registry
- the id of theMetricRegsitry
bean with which the metrics are to be registered- Child elements
<bean />
- The beans to register with the specified registry.metrics:name
attribute on the bean element - specifies the name with which the metric will be registered. Optional if the bean is a MetricSet.
###Java Config Documentation
A @Configuration
class annotated with @EnableMetrics
is functionally equivalent to using the <metrics:annotation-driven />
element.
proxyTargetClass
- if set to true, always creates CGLIB proxies instead of defaulting to JDK proxies. This may be necessary if you use class-based autowiring.exposeProxy
- if set to true, the target can access the proxy which wraps it by callingAopContext.currentProxy()
.
The class may also implement the interface MetricsConfigurer
, or extend the abstract class MetricsConfigurerAdapter
getMetricRegistry()
- return theMetricRegsitry
instance with which metrics should be registered. If omitted a newMetricRegistry
instance is created.getHealthCheckRegistry()
- return theHealthCheckRegsitry
instance with which to register any beans which extend the classHealthCheck
. If omitted a newHealthCheckRegistry
instance is created.configureReporters(MetricRegistry)
- configure reporters
###A Note on the Limitations of Spring AOP
Due to limitations of Spring AOP only public methods can be proxied, so @Timed
, @Metered
, @ExceptionMetered
, and @Counted
have no effect on non-public methods. Additionally, calling an annotated method from within the same class will not go through the proxy.
public class Foo {
@Timed
public void bar() { /* … */ }
public void baz() {
this.bar(); // doesn't pass through the proxy
// fix: reengineer
// workaround: enable `expose-proxy` and change to:
((Foo) AopContext.currentProxy()).bar(); // hideous, but it works
}
}
As @Gauge
doesn’t involve a proxy, it may be used on non-public fields and methods.
Additionally, @InjectMetric
may be used on non-public, non-final fields.
###Users of the Maven Shade plugin
Please see the Shade Readme
###Documentation
Javadocs are hosted at http://ryantenney.github.io/metrics-spring/docs/
YourKit is kindly supporting this open source project with its full-featured Java Profiler. YourKit, LLC is the creator of innovative and intelligent tools for profiling Java and .NET applications. Take a look at YourKit's leading software products: YourKit Java Profiler and YourKit .NET Profiler.
Copyright (c) 2012-2014 Ryan Tenney
Portions Copyright (c) 2012-2013 Martello Technologies
Published under Apache Software License 2.0, see LICENSE