ratpack.codahale.metrics

Class CodaHaleMetricsModule

java.lang.Object

com.google.inject.AbstractModule

ratpack.guice.ConfigurableModule<CodaHaleMetricsModule.Config>

ratpack.codahale.metrics.CodaHaleMetricsModule

All Implemented Interfaces:

com.google.inject.Module

public class CodaHaleMetricsModule
extends ConfigurableModule<CodaHaleMetricsModule.Config>

An extension module that provides support for Coda Hale's Metrics.

To use it one has to register the module and enable the required functionality by chaining the various configuration options. For example, to enable the capturing and reporting of metrics to CodaHaleMetricsModule.Config.jmx(ratpack.func.Action) one would write: (Groovy DSL)

 import ratpack.codahale.metrics.CodaHaleMetricsModule
 import static ratpack.groovy.Groovy.ratpack

 ratpack {
   bindings {
     module new CodaHaleMetricsModule(), { it.jmx() }
   }
 }
 

To enable the capturing and reporting of metrics to JMX and the console, one would write: (Groovy DSL)

 import ratpack.codahale.metrics.CodaHaleMetricsModule
 import static ratpack.groovy.Groovy.ratpack

 ratpack {
   bindings {
     module new CodaHaleMetricsModule(), { it.jmx().console() }
   }
 }
 

External Configuration

The module can also be configured via external configuration using the ratpack-config extension. For example, to enable the capturing and reporting of metrics to jmx via an external property file which can be overridden with system properties one would write: (Groovy DSL)

 import com.google.common.collect.ImmutableMap
 import ratpack.codahale.metrics.CodaHaleMetricsModule
 import ratpack.config.ConfigData
 import static ratpack.groovy.Groovy.ratpack

 ratpack {
   serverConfig {
     props(ImmutableMap.of("metrics.jmx.enabled", "true")) // for demo purposes we are using a map to easily see the properties being set
     sysProps()
     require("/metrics", CodaHaleMetricsModule.Config)
   }

   bindings {
     module CodaHaleMetricsModule
   }
 }
 

Metric Collection

By default Timer metrics are collected for all requests received and Counter metrics for response codes. The module adds a RequestTimingHandler to the handler chain before any user handlers. This means that response times do not take any framework overhead into account and purely the amount of time spent in handlers. It is important that the module is registered first in the modules list to ensure that all handlers are included in the metric.

Additional custom metrics can be registered with the provided MetricRegistry instance

Example custom metrics: (Groovy DSL)

import ratpack.codahale.metrics.CodaHaleMetricsModule
 import com.codahale.metrics.MetricRegistry
 import static ratpack.groovy.Groovy.ratpack

 ratpack {
   bindings {
     module new CodaHaleMetricsModule(), { it.jmx() }
   }

   handlers { MetricRegistry metricRegistry ->
     all {
       metricRegistry.meter("my custom meter").mark()
       render ""
     }
   }
 }
 

Custom metrics can also be added via the Metrics annotations (Metered, Timed and Gauge) to any Guice injected classes.

See Also:

Coda Hale's Metrics

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	CodaHaleMetricsModule.Config The configuration object for CodaHaleMetricsModule.

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	RATPACK_METRIC_REGISTRY

Constructor Summary

Constructors

Constructor and Description
CodaHaleMetricsModule()

Method Summary

Modifier and Type	Method and Description
protected void	configure()

Methods inherited from class ratpack.guice.ConfigurableModule

configure, createConfig, defaultConfig, setConfig

Methods inherited from class com.google.inject.AbstractModule

addError, addError, addError, bind, bind, bind, bindConstant, binder, bindInterceptor, bindListener, bindListener, bindScope, configure, convertToTypes, currentStage, getMembersInjector, getMembersInjector, getProvider, getProvider, install, requestInjection, requestStaticInjection, requireBinding, requireBinding

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

RATPACK_METRIC_REGISTRY

public static final java.lang.String RATPACK_METRIC_REGISTRY

See Also:

Constant Field Values

Constructor Detail

CodaHaleMetricsModule

public CodaHaleMetricsModule()

Method Detail

configure

protected void configure()

Specified by:

configure in class com.google.inject.AbstractModule