Prometheus Metrics

PgQueuer includes a Prometheus integration for real-time metrics on queue performance and job behavior.

Usage

The collect_metrics function returns a Prometheus-formatted string:

from pgqueuer.metrics.prometheus import collect_metrics

content = await collect_metrics(queries)

FastAPI Integration

Install the optional extra:

pip install pgqueuer[fastapi]

Then mount the metrics router:

from pgqueuer.metrics.fastapi import create_metrics_router

app.include_router(create_metrics_router(queries))

The /metrics endpoint will be available for Prometheus to scrape.

Other Frameworks

Use collect_metrics directly and return the result as plain text with content type text/plain; version=0.0.4:

content = await collect_metrics(queries)
return Response(content=content, media_type="text/plain; version=0.0.4")

Standalone Metrics Service

A Docker-based standalone metrics service is available in tools/prometheus. This service uses its own implementation, separate from the pgqueuer.metrics library module.

Building the Image

docker build -t pgq-prometheus-service -f tools/prometheus/Dockerfile .

Running the Service

docker run -p 8000:8000 \
  -e PGHOST=your-postgres-host \
  -e PGDATABASE=your-database \
  -e PGPASSWORD=your-password \
  -e PGUSER=your-username \
  -e PGPORT=5432 \
  pgq-prometheus-service

After the service starts, the metrics endpoint is available at http://localhost:8000/metrics for Prometheus to scrape.