effect-io-ai

Package: effect
Module: Metric

Metric.update

Updates the metric with the specified input.

Details

The behavior of update depends on the metric type. Counters add the input value to the current count, gauges replace the current value with the input value, frequencies increment the occurrence count for the input string, histograms record the input value in the appropriate bucket, and summaries record the input value as a new observation.

Example (Updating metric values)

import { Effect, Metric } from "effect"

const cpuUsage = Metric.gauge("cpu_usage_percent")
const httpStatus = Metric.frequency("http_status_codes")
const responseTime = Metric.histogram("response_time_ms", {
  boundaries: [100, 500, 1000, 2000]
})

const program = Effect.gen(function*() {
  // Update gauge to specific values
  yield* Metric.update(cpuUsage, 45.2)
  yield* Metric.update(cpuUsage, 67.8) // Replaces previous value

  // Track HTTP status code occurrences
  yield* Metric.update(httpStatus, "200")
  yield* Metric.update(httpStatus, "404")
  yield* Metric.update(httpStatus, "200") // Increments 200 count

  // Record response times
  yield* Metric.update(responseTime, 250)
  yield* Metric.update(responseTime, 750)
  yield* Metric.update(responseTime, 1500)

  // Check current states
  const cpu = yield* Metric.value(cpuUsage)
  const statuses = yield* Metric.value(httpStatus)
  const times = yield* Metric.value(responseTime)

  console.log(`CPU Usage: ${cpu.value}%`)
  console.log(`Status 200 count: ${statuses.occurrences.get("200")}`) // 2
  console.log(`Response time samples: ${times.count}`) // 3
})

Signature

declare const update: { <Input>(input: Input): <State>(self: Metric<Input, State>) => Effect<void>; <Input, State>(self: Metric<Input, State>, input: Input): Effect<void>; }

Source

Since v2.0.0