prometheus-nodejs

Goal

Setup monitoring with Prometheus and Grafana on localhost.

Requirements

Nodejs, Docker.

Demo architecture

Steps

1. Run Nodejs server: npm install and npm run start. Open http://localhost:3001. Show metrics with http://localhost:3001/metrics.

2. Install Prometheus and update file config prometheus.yml and file rule.yaml (copy from /config).

   Run ./prometheus --config.file=prometheus.yml from folder you installed. Open Prometheus: http://localhost:9090.

3. Visit your running Prometheus and run queries.

   

   Request Per Minute

   sum(rate(http_request_duration_ms_count[1m])) by (service, route, method, code) * 60

   Error rate

   sum(increase(http_request_duration_ms_count{code=~"^5..$"}[1m])) / sum(increase(http_request_duration_ms_count[1m]))

   Median Response Time

   histogram_quantile(0.5, sum(rate(http_request_duration_ms_bucket[1m])) by (le, service, route, method))

   Average Memory Usage

   avg(nodejs_external_memory_bytes / 1024 / 1024) by (service)

4. Install Prometheus Alertmanager and update file alertmanager.yml.

   

   Run ./alertmanager --config.file=alertmanager.yml and open http://localhost:9093.

   Spam requests to test alert: curl http://localhost:3001/?[1-100].

5. Run Grafana by Docker

   docker run -i -p 3000:3000 grafana/grafana. Open http://localhost:3000.

   Username: admin
   Password: admin
   

   Setting datasource

   Create a Grafana datasource with this settings:

   • name: DS_PROMETHEUS

   • type: prometheus

   • url: http://localhost:9090

   • access: browser

   Create dashboard

   • Import from grafana-dashboard.json.

     

Reference

[1] RisingStack - https://github.com/RisingStack/example-prometheus-nodejs/

[2] Prometheus Docs - https://prometheus.io/docs

[3] Grafana Docs - https://grafana.com/docs/

[4] Prom-client - https://www.npmjs.com/package/prom-client