Compression Tuning

Compression Tuning

Your internal dashboards poll GET/reports/daily around the clock. Each response is about 200KB of JSON — repetitive hourly metric rows, the kind of payload that shrinks ~10× under gzip. Every client sends Accept-Encoding: gzip, and nginx ignores all of them: every report crosses the network raw, byte for byte. The backend team won't add compression ("that's the proxy's job" — they're right), so the fix is yours.

System Architecture

Your task

Enable gzip compression in nginx so every report reaches its client compressed — intact, but ~10× smaller on the wire.

You edit only nginx.conf (the nginx workload, cloned into your dev-vm):

• The backend answers at reports-api:80 with Content-Type: application/json.
• Commit + push → the platform rebuilds the image and restarts nginx.
• A broken config fails nginx at startup — check the deployment logs.

Pass criteria

The grader inspects the wire itself — the Content-Encoding header and the raw transferred bytes — and decompresses every payload to check it's still a valid, complete report. All three must hold:

• Nothing ships uncompressed — zero successful responses with identity encoding.
• Compressed reports keep flowing — a sustained rate of verified-intact gzip responses (blocking or corrupting the payload doesn't count).
• Zero failed requests.

Where to look

• Logs — the simulator's summary shows the split and the savings live: gzip=142 identity=0 wireMB=2.1 decodedMB=21.4 saved=10.2x.
• Monitoring — nginx's NETWORK chart collapses the moment compression lands (CPU ticks up slightly — nothing is free).
• dev-vm — curl -s -o /dev/null -w '%{size_download}\n' -H 'Accept-Encoding: gzip' http://nginx:80/reports/daily: ~200000 means raw, ~25000 means done.

Submit once the split shows identity=0 for a clean minute — submissions are free, so your best score counts.