core/io.github.klient.prometheus.core

Package-level declarations

Types

abstract class Collector(val fullName: String, val help: String, val labelNames: List<String> = emptyList(), val unit: String = "")

Abstract base class for all Prometheus metric collectors.

CollectorRegistry

class CollectorRegistry

A thread-safe registry for Collector instances.

Counter

class Counter : SimpleCollector<Counter.Child>

A Counter is a metric that only increases (monotonically), typically used for counting occurrences.

CounterBuilder

class CounterBuilder : MetricBuilder<Counter>

Builder class for creating Counter metrics.

Gauge

class Gauge : SimpleCollector<Gauge.Child>

A Gauge is a metric that represents a single numerical value that can go up and down.

GaugeBuilder

class GaugeBuilder(name: String) : MetricBuilder<Gauge>

Builder class for creating Gauge metrics.

Histogram

class Histogram : SimpleCollector<Histogram.Child>

A histogram metric that tracks the distribution of values over a set of buckets.

HistogramBuilder

class HistogramBuilder(name: String, buckets: List<Double>? = null) : MetricBuilder<Histogram>

Builder class for creating Histogram metrics.

MetricBuilder

abstract class MetricBuilder<T : SimpleCollector<*>>

Base class for building SimpleCollector instances with a fluent and idiomatic DSL.

PrometheusExporter

class PrometheusExporter

Exports Prometheus metrics from a CollectorRegistry in the Prometheus text exposition format.

PrometheusTextFormat

class PrometheusTextFormat

A Prometheus text format encoder (version 0.0.4).

Quantiles

class Quantiles(quantiles: Array<Quantiles.Quantile>)

SimpleCollector

abstract class SimpleCollector<Child>(val fullName: String, val help: String, val labelNames: List<String>, val unit: String) : Collector

Abstract base class for Prometheus metric types that support labeled children.

SimpleTimer

class SimpleTimer

Summary

class Summary : SimpleCollector<Summary.Child>

A Summary is a metric that provides statistical information about observed values, including quantiles.

SummaryBuilder

class SummaryBuilder : MetricBuilder<Summary>

Builder class for creating Summary metrics.

TimeWindowQuantiles

class TimeWindowQuantiles(quantiles: Array<Quantiles.Quantile>, maxAgeSeconds: Long, ageBuckets: Int)

ValueHistogram

data class ValueHistogram(val sum: Double, val buckets: List<Double>, val created: Long)

Represents the current state of a histogram, including the sum of observed values, the cumulative counts for each bucket, and the creation timestamp.

ValueSummary

data class ValueSummary(val count: Double, val sum: Double, val quantiles: Map<Double, Double>?, val created: Long)

Represents the current state of a summary, including the count, sum, quantiles, and creation timestamp.

Functions

counter

fun counter(name: String, block: CounterBuilder.() -> Unit): Counter

DSL-style function to build and register a Counter using a CounterBuilder.

countExceptions

suspend fun <T> Counter.countExceptions(vararg exceptionTypes: KClass<out Throwable>, block: () -> T): T?

suspend fun <T> Counter.Child.countExceptions(vararg exceptionTypes: KClass<out Throwable>, block: () -> T): T?

Executes the given block and increments the counter if an exception of the specified types is thrown.

doubleQuoteString

fun doubleQuoteString(s: String): String

Ensures a given string is surrounded by double quotes, correcting partial quotes.

exponentialHistogramBuckets

fun exponentialHistogramBuckets(name: String, block: HistogramBuilder.() -> Unit, start: Double, factor: Double, count: Int): Histogram

Creates a histogram with exponentially spaced buckets.

gauge

fun gauge(name: String, block: GaugeBuilder.() -> Unit): Gauge

DSL-style function to build and register a Gauge using a GaugeBuilder.

getClassName

fun Collector.getClassName(): String

Returns the simple class name of the Collector instance.

getCurrentMillis

fun getCurrentMillis(clock: Clock = Clock.System): Long

Returns the current Unix timestamp in milliseconds from the given Clock.

getCurrentSeconds

fun getCurrentSeconds(clock: Clock = Clock.System): Long

Returns the current Unix timestamp in seconds from the given Clock.

histogram

fun histogram(name: String, block: HistogramBuilder.() -> Unit): Histogram

A DSL-style function to create and register a Histogram using a HistogramBuilder. Creates a histogram with the specified name and configuration defined in the block.

histogramBuckets

fun histogramBuckets(name: String, block: HistogramBuilder.() -> Unit, buckets: List<Double>): Histogram

Creates a histogram with predefined buckets.

linearHistogramBuckets

fun linearHistogramBuckets(name: String, block: HistogramBuilder.() -> Unit, start: Double, width: Double, count: Int): Histogram

Creates a histogram with linearly spaced buckets.

quantile

fun quantile(quantile: Double, error: Double = 0.01): Quantiles.Quantile

Creates a quantile for use in summaries.

quantiles

fun quantiles(vararg quantiles: Quantiles.Quantile): List<Quantiles.Quantile>

Converts a variable number of quantiles into a list.

setDuration

suspend fun <T> Gauge.setDuration(block: () -> T): T

Measures the duration of a block and stores it in the unlabeled gauge.

suspend fun <T> Gauge.Child.setDuration(block: () -> T): T

Measures the duration of a block and stores it in the labeled Gauge.Child.

summary

fun summary(name: String, block: SummaryBuilder.() -> Unit): Summary

Creates a summary without predefined quantiles.

summaryQuantiles

fun summaryQuantiles(name: String, block: SummaryBuilder.() -> Unit, quantiles: List<Quantiles.Quantile>, maxAgeSeconds: Long = 60, ageBuckets: Int = 5): Summary

Creates a summary with predefined quantiles.

track

inline suspend fun <T> Gauge.track(block: () -> T): T

Increments the unlabeled gauge while the block is running, and decrements it when the block completes.

inline suspend fun <T> Gauge.Child.track(block: () -> T): T

Increments the labeled gauge while the block is running, and decrements it when the block completes.