@dxdeveloperexperience/hygie/src/logger/prometheus.service.ts

Hygie is an easy-to-use Open-Source REST API allowing you to interact with GIT events. This NestJS API expose a set of customizable rules to automate your project's life cycle.

import { Injectable } from '@nestjs/common';
import { logger } from './logger.service';

@Injectable()
export class PrometheusService {
  checkoutsTotal;
  httpRequestDurationMicroseconds;
  Prometheus;
  constructor() {
    this.Prometheus = require('prom-client');
    try {
      this.Prometheus.collectDefaultMetrics();
    } catch (err) {
      logger.error(err, { location: 'Prometheus 1' });
    }

    try {
      this.httpRequestDurationMicroseconds = new this.Prometheus.Histogram({
        name: 'http_request_duration_ms',
        help: 'Duration of HTTP requests in ms',
        labelNames: ['method', 'route', 'code'],
        buckets: [50, 100, 200, 300, 400, 500, 750, 1000], // buckets for response time from 50ms to 1000ms
      });
    } catch (e) {
      logger.error(e, { location: 'Prometheus 2' });
    }
  }
}