# Container Setup

OCI container image for the apartment finder. Runs two processes:

1. **Web server** (`python3 -m http.server`) serving `mapa_bytu.html` on port 8080
2. **Cron job** running `run_all.sh` (all 6 scrapers + merge) every 12 hours

## Architecture

```
┌─────────────────────────────────────────┐
│  Container (python:3.13-alpine)         │
│                                         │
│  PID 1: python3 -m http.server :8080    │
│         serves /app/data/               │
│                                         │
│  crond:  runs run_all.sh at 06:00/18:00 │
│          Europe/Prague timezone          │
│                                         │
│  /app/        ← scripts (.py, .sh)      │
│  /app/data/   ← volume (JSON + HTML)    │
│         ↑ symlinked from /app/byty_*    │
└─────────────────────────────────────────┘
```

On startup, the web server starts immediately. The initial scrape runs in the background and populates data as it completes. Subsequent cron runs update the data in-place.

## Build and Run

```bash
# Build the image
docker build -t maru-hleda-byt .

# Run with persistent data volume
docker run -d --name maru-hleda-byt \
  -p 8080:8080 \
  -v maru-hleda-byt-data:/app/data \
  --restart unless-stopped \
  maru-hleda-byt
```

Access the map at **http://localhost:8080/mapa_bytu.html**

## Volume Persistence

A named volume `maru-hleda-byt-data` stores:

- `byty_*.json` — cached scraper data (6 source files + 1 merged)
- `mapa_bytu.html` — the generated interactive map

The JSON cache is important: each scraper skips re-fetching properties that haven't changed. Without the volume, every container restart triggers a full re-scrape of all 6 portals (several minutes with rate limiting).

## Cron Schedule

Scrapers run at **06:00** and **18:00 Europe/Prague time** (CET/CEST).

Cron output is forwarded to the container's stdout/stderr, visible via `docker logs`.

## Operations

```bash
# View logs (including cron and scraper output)
docker logs -f maru-hleda-byt

# Check cron schedule
docker exec maru-hleda-byt crontab -l

# Trigger a manual scrape
docker exec maru-hleda-byt bash /app/run_all.sh

# Stop / start (data persists in volume)
docker stop maru-hleda-byt
docker start maru-hleda-byt

# Rebuild after code changes
docker stop maru-hleda-byt && docker rm maru-hleda-byt
docker build -t maru-hleda-byt .
docker run -d --name maru-hleda-byt \
  -p 8080:8080 \
  -v maru-hleda-byt-data:/app/data \
  --restart unless-stopped \
  maru-hleda-byt
```

## Troubleshooting

**Map shows 404**: The initial background scrape hasn't finished yet. Check `docker logs` for progress. First run takes a few minutes due to rate-limited API calls.

**SSL errors from PSN scraper**: The `scrape_psn.py` uses `curl` (not Python urllib) specifically for Cloudflare SSL compatibility. Alpine's curl includes modern TLS via OpenSSL, so this should work. If not, check that `ca-certificates` is installed (`apk add ca-certificates`).

**Health check failing**: The health check has a 5-minute start period to allow the initial scrape to complete. If it still fails, verify the HTTP server is running: `docker exec maru-hleda-byt wget -q -O /dev/null http://localhost:8080/`.

**Timezone verification**: `docker exec maru-hleda-byt date` should show Czech time.

## Image Details

- **Base**: `python:3.13-alpine` (~55 MB)
- **Added packages**: `curl`, `bash`, `tzdata` (~10 MB)
- **No pip packages** — all scrapers use Python standard library only
- **Approximate image size**: ~70 MB