Type Members

1.  trait Metric[+Type, -In, +Out] extends ZIOAspect[Nothing, Any, Nothing, Any, Nothing, In]

   A Metric[In, Out] represents a concurrent metric, which accepts updates of type In, which are aggregated to a stateful value of type Out.

   A Metric[In, Out] represents a concurrent metric, which accepts updates of type In, which are aggregated to a stateful value of type Out.

   For example, a counter metric would have type Metric[Double, Double], representing the fact that the metric can be updated with doubles (the amount to increment or decrement the counter by), and the state of the counter is a double.

   There are five primitive metric types supported by ZIO:

   • Counters
   • Frequencies
   • Gauges
   • Histograms
   • Summaries

   The companion object contains constructors for these primitive metrics. All metrics are derived from these primitive metrics.

2.  sealed case class MetricKey[+Type] extends Product with Serializable

   A MetricKey is a unique key associated with each metric.

   A MetricKey is a unique key associated with each metric. The key is based on a combination of the metric type, the name and tags associated with the metric, and any other information to describe a a metric, such as the boundaries of a histogram. In this way, it is impossible to ever create different metrics with conflicting keys.

3.  sealed trait MetricKeyType extends AnyRef
4.  final case class MetricLabel(key: String, value: String) extends Product with Serializable

   A MetricLabel represents a key value pair that allows analyzing metrics at an additional level of granularity.

   A MetricLabel represents a key value pair that allows analyzing metrics at an additional level of granularity. For example if a metric tracks the response time of a service labels could be used to create separate versions that track response times for different clients.

5.  final case class MetricPair[Type <: MetricKeyType { type Out = Out0 }, Out0](metricKey: MetricKey[Type], metricState: MetricState[Out0]) extends Product with Serializable
6.  sealed trait MetricState[+Type] extends AnyRef

   A MetricState describes the state of a metric.

   A MetricState describes the state of a metric. The type parameter of a metric state corresponds to the type of the metric key (MetricKeyType). This phantom type parameter is used to tie keys to their expected states.

7.  final case class Metrics extends Product with Serializable
8.  trait PollingMetric[-R, +E, +Out] extends AnyRef

   A PollingMetric[Type, Out] is a combination of a metric and an effect that polls for updates to the metric.