connorlindsey / otel-grafana-demo

Demo application showing how to instrument a Node application with OpenTelemetry, Prometheus, Jaeger, Loki, and Grafana. Built with Next.js, Fastify, and Postgres.

OpenTelemetry - Grafana Demo

Author: Connor Lindsey

This demo application demonstrates how to monitor a JavaScript application using open source observability software. The following projects are used:

• OpenTelemetry - Instrument the application and send observability data to each backend.
• Jaeger - Distributed tracing backend.
• Prometheus - Metrics and alerting backend.
• Loki - Logs aggregation system.
• Grafana - Visualize all of our observability data.

Project Structure

• api/ - Fastify API. Instrumented with OpenTelemetry
• app/ - Simple Next.js app.
• db/ - Stores copy of Postgres data for persistence.
• config/ - Standard configuration for Prometheus, Promtail, Loki, etc.
• data/ - Stores server logs

Running the app

1. Run with npm run dev. Requires Docker and docker-compose.
2. Optionally, run npm install in /api and /app.
3. Open the app at http://localhost
4. View traces, logs, and metrics in Grafana at http://localhost:3000

Additional Resources

• Grafana Demo
• Grafana Cloud - Actually useful free tier
• OpenTelemetry Key Terms
• OpenTelemetry JS
• OpenTelemetry JS Contrib
• OpenTelemetry Status
• UtahJS Slides