package kamon.metric
import java.time.temporal.ChronoUnit
import java.time.Duration
import kamon.Kamon
import kamon.testkit.{MetricInspection, Reconfigure}
import org.scalatest.{BeforeAndAfterAll, Matchers, OptionValues, WordSpec}
class PeriodSnapshotAccumulatorSpec extends WordSpec with Reconfigure with MetricInspection with Matchers
with BeforeAndAfterAll with OptionValues {
"the PeriodSnapshotAccumulator" should {
"allow to peek on an empty accumulator" in {
val accumulator = newAccumulator(10, 1)
val periodSnapshot = accumulator.peek()
periodSnapshot.metrics.histograms shouldBe empty
periodSnapshot.metrics.rangeSamplers shouldBe empty
periodSnapshot.metrics.gauges shouldBe empty
periodSnapshot.metrics.counters shouldBe empty
}
"bypass accumulation if the configured duration is equal to the metric tick-interval, regardless of the snapshot" in {
val accumulator = newAccumulator(10, 1)
accumulator.add(tenSeconds).value should be theSameInstanceAs(tenSeconds)
accumulator.add(fiveSecondsOne).value should be theSameInstanceAs(fiveSecondsOne)
}
"bypass accumulation if snapshots have a period longer than duration minus margin" in {
val accumulator = newAccumulator(4, 1)
accumulator.add(almostThreeSeconds) shouldBe empty
accumulator.add(threeSeconds).value should be theSameInstanceAs(threeSeconds)
accumulator.add(fourSeconds).value should be theSameInstanceAs(fourSeconds)
accumulator.add(nineSeconds).value should be theSameInstanceAs(nineSeconds)
}
"allow to peek into the data that has been accumulated" in {
val accumulator = newAccumulator(20, 1)
accumulator.add(fiveSecondsOne) shouldBe empty
accumulator.add(fiveSecondsTwo) shouldBe empty
for(_ <- 1 to 10) {
val peekSnapshot = accumulator.peek()
val mergedHistogram = peekSnapshot.metrics.histograms.head
val mergedRangeSampler = peekSnapshot.metrics.rangeSamplers.head
peekSnapshot.metrics.counters.head.value shouldBe (55)
peekSnapshot.metrics.gauges.head.value shouldBe (33)
mergedHistogram.distribution.buckets.map(_.value) should contain allOf(22L, 33L)
mergedRangeSampler.distribution.buckets.map(_.value) should contain allOf(22L, 33L)
}
accumulator.add(fiveSecondsThree) shouldBe empty
for(_ <- 1 to 10) {
val peekSnapshot = accumulator.peek()
val mergedHistogram = peekSnapshot.metrics.histograms.head
val mergedRangeSampler = peekSnapshot.metrics.rangeSamplers.head
peekSnapshot.metrics.counters.head.value shouldBe (67)
peekSnapshot.metrics.gauges.head.value shouldBe (12)
mergedHistogram.distribution.buckets.map(_.value) should contain allOf(22L, 33L, 12L)
mergedRangeSampler.distribution.buckets.map(_.value) should contain allOf(22L, 33L, 12L)
}
}
"produce a snapshot when enough data has been accumulated" in {
val accumulator = newAccumulator(15, 1)
accumulator.add(fiveSecondsOne) shouldBe empty
accumulator.add(fiveSecondsTwo) shouldBe empty
val snapshotOne = accumulator.add(fiveSecondsThree).value
snapshotOne.from shouldBe fiveSecondsOne.from
snapshotOne.to shouldBe fiveSecondsThree.to
val mergedHistogram = snapshotOne.metrics.histograms.head
val mergedRangeSampler = snapshotOne.metrics.rangeSamplers.head
snapshotOne.metrics.counters.head.value shouldBe(67)
snapshotOne.metrics.gauges.head.value shouldBe(12)
mergedHistogram.distribution.buckets.map(_.value) should contain allOf(22L, 33L, 12L)
mergedRangeSampler.distribution.buckets.map(_.value) should contain allOf(22L, 33L, 12L)
val emptySnapshot = accumulator.peek()
emptySnapshot.metrics.histograms shouldBe empty
emptySnapshot.metrics.rangeSamplers shouldBe empty
emptySnapshot.metrics.gauges shouldBe empty
emptySnapshot.metrics.counters shouldBe empty
accumulator.add(fiveSecondsFour) shouldBe empty
}
}
val zeroTime = Kamon.clock().instant().truncatedTo(ChronoUnit.SECONDS)
val fiveSecondsOne = PeriodSnapshot(zeroTime, zeroTime.plusSeconds(5), createMetricsSnapshot(22))
val fiveSecondsTwo = PeriodSnapshot(zeroTime.plusSeconds(5), zeroTime.plusSeconds(10), createMetricsSnapshot(33))
val fiveSecondsThree = PeriodSnapshot(zeroTime.plusSeconds(10), zeroTime.plusSeconds(15), createMetricsSnapshot(12))
val fiveSecondsFour = PeriodSnapshot(zeroTime.plusSeconds(15), zeroTime.plusSeconds(20), createMetricsSnapshot(37))
val almostThreeSeconds = PeriodSnapshot(zeroTime, zeroTime.plusSeconds(3).minusMillis(1), createMetricsSnapshot(22))
val threeSeconds = PeriodSnapshot(zeroTime, zeroTime.plusSeconds(3), createMetricsSnapshot(22))
val fourSeconds = PeriodSnapshot(zeroTime, zeroTime.plusSeconds(4), createMetricsSnapshot(22))
val nineSeconds = PeriodSnapshot(zeroTime, zeroTime.plusSeconds(9), createMetricsSnapshot(22))
val tenSeconds = PeriodSnapshot(zeroTime, zeroTime.plusSeconds(10), createMetricsSnapshot(36))
def newAccumulator(duration: Long, margin: Long) =
new PeriodSnapshotAccumulator(Duration.ofSeconds(duration), Duration.ofSeconds(margin))
def createMetricsSnapshot(value: Long) = MetricsSnapshot(
histograms = Seq(createDistributionSnapshot(s"histogram", Map("metric" -> "histogram"), MeasurementUnit.time.microseconds, DynamicRange.Fine)(value)),
rangeSamplers = Seq(createDistributionSnapshot(s"gauge", Map("metric" -> "gauge"), MeasurementUnit.time.microseconds, DynamicRange.Default)(value)),
gauges = Seq(createValueSnapshot(s"gauge", Map("metric" -> "gauge"), MeasurementUnit.information.bytes, value)),
counters = Seq(createValueSnapshot(s"counter", Map("metric" -> "counter"), MeasurementUnit.information.bytes, value))
)
def createValueSnapshot(metric: String, tags: Map[String, String], unit: MeasurementUnit, value: Long): MetricValue = {
MetricValue(metric, tags, unit, value)
}
def createDistributionSnapshot(metric: String, tags: Map[String, String], unit: MeasurementUnit, dynamicRange: DynamicRange)(values: Long*): MetricDistribution = {
val histogram = Kamon.histogram(metric, unit, dynamicRange).refine(tags)
values.foreach(histogram.record)
val distribution = histogram.distribution(resetState = true)
MetricDistribution(metric, tags, unit, dynamicRange, distribution)
}
override protected def beforeAll(): Unit = {
applyConfig("kamon.metric.tick-interval = 10 seconds")
}
}
