Competitor Watch + Slack Alerts (Spec #5 demo)

Catalog price-monitoring as a service. Snapshots a target catalog, diffs against last run, posts to Slack on any price/availability/added/removed change.

Run

cd ~/freelance/portfolio_demos/competitor_watch
. ~/freelance/.venv/bin/activate
python3 monitor.py --reset --target "http://books.toscrape.com/"   # baseline
python3 monitor.py --target "http://books.toscrape.com/"           # noop on no change
python3 monitor.py --simulate-price-change "A Light in the Attic" 99.99
python3 monitor.py --target "http://books.toscrape.com/"           # alert fires

Result (last run)

• Run 1 (baseline): 20 products saved, no alert ✅
• Run 2 (no change): noop ✅
• Run 3 (after simulated price tweak): alert fires, posted to Slack COO channel ✅

Slack alert format

:eyes: Catalog change detected on http://books.toscrape.com/

:moneybag: 1 price change
   • A Light in the Attic — £99.99 → £51.77

Files

• monitor.py — fetch + diff + alert
• state.json — last snapshot (gitignored)
• watch_log.jsonl — audit log of every run