Provides a set of Play2 injectable extentsions for Kamon.
Add library as a dependency:
"au.com.agiledigital" %% "play-kamon-extensions" % "0.6"Enable the Play2 module in application.conf
play.modules.enabled += "au.com.agiledigital.kamon.play_extensions.KamonPlayExtensionsModule"To use, inject (or otherwise obtain) an instance of au.com.agiledigital.kamon.play_extensions.Metrics. Once obtained, you can use as a substitute for the methods available on Kamon's Tracer object.
Asychronous traces (optionally autocompleted and counted) can be started using withNewAsyncContext:
import javax.inject.Inject
import au.com.agiledigital.kamon.play_extensions.Metrics
import scala.concurrent.Future
class Service @Inject()(metrics: Metrics) {
def doSomething(): Future[Int] = {
metrics.withNewAsyncContext("doingSomething", autoFinish = true, count = true) {
Future.successful(10)
}
}
}Traces can be named automatically using traced and tracedAsync. Naming semantics are determined by sourcecode.
import javax.inject.Inject
import au.com.agiledigital.kamon.play_extensions.Metrics
import scala.concurrent.Future
class Service @Inject()(metrics: Metrics) {
def doSomething(): Future[Int] = metrics.tracedAsync {
Future.successful(10)
}
}By default Kamon records all trace metrics under statsd.timer.$Application.$Host.trace. The extensions support writing those metrics to nested categories.
To create nested trace categories, use withCategory
import javax.inject.Inject
import au.com.agiledigital.kamon.play_extensions.Metrics
import scala.concurrent.Future
class Service @Inject()(metrics: Metrics) {
private val serviceMetrics = metrics.withCategory("service")
def doSomething(): Future[Int] = metrics.tracedAsync {
Future.successful(10)
}
}This will cause metrics for those traces to be written to statsd.timer.$Application.$Host.trace.service
To aid testing code that depends upon the Metrics extension, depend upon the testkit:
"au.com.agiledigital" %% "play-kamon-extensions-testkit" % "0.5"Use the do-nothing Metrics implementation from au.com.agiledigital.kamon.play_extensions.test#metrics
