What is the OpenTelemetry Astronomy Shop, and why is an entire web shop used to demonstrate observability?
It is the OpenTelemetry project's official demo: a realistic microservice web shop for telescopes and star charts whose real purpose is to produce traces, metrics and logs worth analysing.
To a visitor it looks like an ordinary online shop: browse the catalogue, fill a cart, check out. The shop itself is beside the point. What matters is what happens behind the page, where more than a dozen services, written in different languages, cooperate to serve every click. That is exactly the kind of system observability exists for, and exactly the kind that is hard to build just for a classroom.
A toy "hello world" service would not show anything interesting. A single request in the Astronomy Shop crosses the frontend, the checkout, payment, shipping, currency and email services, so a trace of it has depth, a slow service has somewhere to hide, and a failure has something to cascade through. Every service is already instrumented with OpenTelemetry, and the demo ships with the backends to look at the data (Jaeger, Prometheus, Grafana, OpenSearch), so the whole pipeline from instrumented code to dashboard can be explored on one laptop with docker compose up.
In a local installation everything sits behind one port: the shop at http://localhost:8080, Grafana at /grafana/, the Jaeger UI at /jaeger/ui/, and Prometheus on port 9090.
Go deeper:
OpenTelemetry Demo documentation — the official overview, including screenshots of each backend.
open-telemetry/opentelemetry-demo on GitHub — the source; the README has the one-command Docker and Kubernetes setups.
Tracetest — Astronomy Shop Demo — installation walkthrough for running the shop locally.