Observability Stack for DevOps

Metrics, logs, and traces — one docker compose up away.

What's in the box

Prometheus  ← scrapes ← Node Exporter, cAdvisor, OTEL Collector
Loki        ← pushes  ← Promtail (container logs)
OTEL        ← OTLP    → exports metrics to Prometheus
Grafana     → queries  → Prometheus + Loki (auto-provisioned)
Notes App   → demo workload

Quick start

git clone https://github.com/yourusername/Observability-For-DevOps.git
cd Observability-For-DevOps
docker compose up -d

That's it. Open http://localhost:3000 (admin/admin).

Endpoints

Service	URL	What it does
Grafana	:3000	Dashboards for metrics + logs
Prometheus	:9090	Metrics store, check /targets
Loki	:3100	Log aggregation backend
cAdvisor	:8080	Container resource metrics
OTEL Collector	:4317 gRPC / :4318 HTTP	Send OTLP traces, metrics, logs
Notes App	:8000	Sample Django app

Node Exporter and Promtail run internally (no exposed ports needed).

Sending traces to OTEL

The collector accepts OTLP on ports 4317 (gRPC) and 4318 (HTTP). Point your instrumented app at it:

# quick test
curl -X POST http://localhost:4318/v1/traces \
  -H 'Content-Type: application/json' \
  -d '{"resourceSpans":[{"resource":{"attributes":[{"key":"service.name","value":{"stringValue":"my-app"}}]},"scopeSpans":[{"spans":[{"traceId":"aaaabbbbccccddddaaaabbbbccccdddd","spanId":"aaaabbbbccccdddd","name":"test","kind":1,"startTimeUnixNano":"1000000000","endTimeUnixNano":"2000000000","status":{}}]}]}]}'

Metrics from OTLP get exported to Prometheus. Traces go to debug logs (swap in Jaeger/Tempo when ready).

Project structure

.
├── docker-compose.yml
├── prometheus.yml                          # scrape config
├── otel-collector/otel-collector-config.yml
├── loki/loki-config.yml
├── promtail/promtail-config.yml
├── grafana/provisioning/
│   ├── datasources/datasources.yml         # Prometheus + Loki
│   └── dashboards/dashboards.yml           # drop JSON files in dashboards/json/
└── notes-app/                              # Django demo app

Tear down

docker compose down          # stop everything
docker compose down -v       # stop + delete all data