# Web On The Fly

Flask app that queues requests, then streams AI-generated fake websites via SSE through a Valkey-backed worker.

This is a Podman project. Use `podman` instead of `docker` for all container commands.

## Commands

- `uv run app.py` — start dev server (includes worker thread) on port 5000
- `uv run pyright app.py` — typecheck (strict mode)
- `uv run ruff check app.py` — lint
- `uv run ruff check app.py --fix` — auto-fix lint issues
- `podman compose up -d` — start Valkey (required dependency)

Run lint/typecheck after any code changes.

## Architecture

- Single file: `app.py`
- Valkey (Redis-compatible) is required for request queuing, chunk buffering, and worker coordination
- Request flow:
  - `/` → loading page with SSE client
  - `/stream` → enqueues request in Valkey, then polls for worker-generated chunks
  - Background worker (thread in dev, gunicorn_post_fork in prod) pops from queue, calls LLM, buffers base64-encoded chunks
  - Client decodes chunks in-memory, replaces document on `[RENDER]`
- After LLM generation: validates HTML with lxml + LLM JS review, auto-fixes up to 2 times
- THEMES list (50+ items): tuples of `(site_type, description)` — worker picks randomly

## Env vars (loaded from `.env` via python-dotenv)

- `OPENAI_API_KEY` — required
- `OPENAI_API_URL` — OpenAI-compatible endpoint (code default: `https://api.openai.com/v1/chat/completions`; `.env.example` uses `https://aipi.reeseapps.com/v1/chat/completions`)
- `MODEL` — model name (code default: `gpt-4o-mini`; `.env.example` uses `turbo`)
- `VALKEY_URL` — Valkey/Redis URL (default: `redis://localhost:6379/0`)

## Production

- Runs via gunicorn: 16 workers, 300s timeout
- `gunicorn_post_fork` hook ensures exactly one worker thread across processes (Valkey-based lock)
- Containerfile uses `uv sync --frozen --no-dev`, runs with `uv run --no-sync`

## Key details

- LLM streaming uses `stream=True`; chunks are base64-encoded to avoid SSE protocol breaks
- HTTP timeout is 300s (long generations)
- `pyright` is configured in strict mode; use `# noqa: BLE001` for intentional broad exception catches
- `lxml.html` is imported dynamically via `importlib.import_module`