@libp2p/prometheus-metrics
Version:
Collect libp2p metrics for scraping by Prometheus or Graphana
49 lines (40 loc) • 1.48 kB
text/typescript
import { Counter as PromCounter } from 'prom-client'
import { normalizeString } from './utils.js'
import type { PrometheusCalculatedMetricOptions } from './index.js'
import type { CounterGroup } from '@libp2p/interface'
import type { CollectFunction } from 'prom-client'
export class PrometheusCounterGroup implements CounterGroup {
private readonly counter: PromCounter
private readonly label: string
constructor (name: string, opts: PrometheusCalculatedMetricOptions<Record<string, number>>) {
name = normalizeString(name)
const help = normalizeString(opts.help ?? name)
const label = this.label = normalizeString(opts.label ?? name)
let collect: CollectFunction<PromCounter<any>> | undefined
// calculated metric
if (opts?.calculate != null) {
collect = async function () {
const values = await opts.calculate()
Object.entries(values).forEach(([key, value]) => {
this.inc({ [label]: key }, value)
})
}
}
this.counter = new PromCounter({
name,
help,
labelNames: [this.label],
registers: opts.registry !== undefined ? [opts.registry] : undefined,
collect
})
}
increment (values: Record<string, number | unknown>): void {
Object.entries(values).forEach(([key, value]) => {
const inc = typeof value === 'number' ? value : 1
this.counter.inc({ [this.label]: key }, inc)
})
}
reset (): void {
this.counter.reset()
}
}