1 import { Application, Request, Response } from 'express'
2 import { Meter, metrics } from '@opentelemetry/api-metrics'
3 import { PrometheusExporter } from '@opentelemetry/exporter-prometheus'
4 import { MeterProvider } from '@opentelemetry/sdk-metrics-base'
5 import { logger } from '@server/helpers/logger'
6 import { CONFIG } from '@server/initializers/config'
7 import { JobQueue } from '../job-queue'
8 import { StatsObserverBuilder } from './metric-helpers'
10 class OpenTelemetryMetrics {
12 private static instance: OpenTelemetryMetrics
16 private onRequestDuration: (req: Request, res: Response) => void
18 private constructor () {}
20 init (app: Application) {
21 if (CONFIG.OPEN_TELEMETRY.METRICS.ENABLED !== true) return
23 app.use((req, res, next) => {
24 res.once('finish', () => {
25 if (!this.onRequestDuration) return
27 this.onRequestDuration(req as Request, res as Response)
35 if (CONFIG.OPEN_TELEMETRY.METRICS.ENABLED !== true) return
37 logger.info('Registering Open Telemetry metrics')
39 const provider = new MeterProvider()
41 provider.addMetricReader(new PrometheusExporter({ port: CONFIG.OPEN_TELEMETRY.METRICS.PROMETHEUS_EXPORTER.PORT }))
43 metrics.setGlobalMeterProvider(provider)
45 this.meter = metrics.getMeter('default')
47 this.buildMemoryObserver()
48 this.buildRequestObserver()
49 this.buildJobQueueObserver()
51 const statsObserverBuilder = new StatsObserverBuilder(this.meter)
52 statsObserverBuilder.buildObservers()
55 private buildMemoryObserver () {
56 this.meter.createObservableGauge('nodejs_memory_usage_bytes', {
58 }).addCallback(observableResult => {
59 const current = process.memoryUsage()
61 observableResult.observe(current.heapTotal, { memoryType: 'heapTotal' })
62 observableResult.observe(current.heapUsed, { memoryType: 'heapUsed' })
63 observableResult.observe(current.arrayBuffers, { memoryType: 'arrayBuffers' })
64 observableResult.observe(current.external, { memoryType: 'external' })
65 observableResult.observe(current.rss, { memoryType: 'rss' })
69 private buildJobQueueObserver () {
70 this.meter.createObservableGauge('peertube_job_queue_total', {
71 description: 'Total jobs in the PeerTube job queue'
72 }).addCallback(async observableResult => {
73 const stats = await JobQueue.Instance.getStats()
75 for (const { jobType, counts } of stats) {
76 for (const state of Object.keys(counts)) {
77 observableResult.observe(counts[state], { jobType, state })
83 private buildRequestObserver () {
84 const requestDuration = this.meter.createHistogram('http_request_duration_ms', {
86 description: 'Duration of HTTP requests in ms'
89 this.onRequestDuration = (req: Request, res: Response) => {
90 const duration = Date.now() - res.locals.requestStart
92 requestDuration.record(duration, {
93 path: this.buildRequestPath(req.originalUrl),
95 statusCode: res.statusCode + ''
100 private buildRequestPath (path: string) {
101 return path.split('?')[0]
104 static get Instance () {
105 return this.instance || (this.instance = new this())