architecture

Official REST. aiohttp. status=="OK" or it is an error. Path param is userid because the first version of this API used that word. The Codeforces word is handle. Envelope platform is "codeforces".

python app.py binds 127.0.0.1:8000 in production mode and 58353 in development. Use 8003.

This is the only stats API with first-class non-user routes: upcoming contests, common contests, /multi/{userids}. Those five are deprecated=True in OpenAPI and still useful. Canonical card composition should go through /{userid}/profile and /{userid}/contests.

flowchart LR
  Browser --> API["codeforces-stats.tashif.codes"]
  API --> CF["codeforces.com/api"]

Heatmap, stats, and topics all re-fetch user.status. That list is the expensive call. Distinct solved is (contestId, index) with verdict=="OK". Topics are problem tags. No difficulty buckets. Badges empty.

get_contests_participated_by_user sleeps 2s first. Codeforces bans noisy IPs. The local Redis limiter is a courtesy, not a substitute. Full walk of CacheRateLimitMiddleware(platform="codeforces") is on Request path. A cache HIT skips that 2s sleep.