# Repository Guide

## Current architecture

- `frontend`: React Router SPA. Production files are built in `nginx/Dockerfile`.
- `backend`: public FastAPI API and internal RustFS storage API in one process.
- `runtime`: shared Jupyter lifecycle, MySQL edit leases and short-lived in-memory access tickets.
- `schedule`: APScheduler, MySQL JobStore, MySQL Outbox polling and DAG execution.
- `common`: SQLAlchemy models, database/session helpers, IDs and object-store helpers.
- `migrations`: Alembic schema and seed migrations.
- `nginx`: static frontend, `/api/` proxy and authenticated `/jupyter/` proxy.

Redis and the former separate Storage API container are intentionally removed.

## Commands

From the repository root:

```bash
# Local Python workspace
uv sync --all-packages

# Static Python check
python -m compileall common/src backend/src runtime/src schedule/src

# Database migration
uv run --package backend alembic upgrade head

# Full Docker stack
cp .env.example .env
docker compose config
docker compose up -d --build
```

Frontend development:

```bash
cd frontend
pnpm install
pnpm dev
pnpm typecheck
pnpm build
```

## Service rules

- Browser traffic enters through Gateway only.
- Frontend API calls use same-origin `/api/v1/...` paths.
- Backend writes `schedule_runs` and `outbox_events`, then performs best-effort HTTP dispatch to Schedule Executor.
- Schedule Executor always polls pending MySQL Outbox rows, so HTTP dispatch failure does not lose a task.
- Cron jobs are persisted by APScheduler in MySQL table `apscheduler_jobs`.
- Runtime must stay single-replica while file leases and Jupyter tickets use the simplified implementation.
- Never expose the internal Jupyter token to the browser.
- Never delete Docker volumes when preserving MySQL or RustFS data is required.

## Main entrypoints

```text
frontend/app/routes/platform.tsx
backend/src/backend/main.py
runtime/src/runtime/main.py
schedule/src/schedule/main.py
nginx/default.conf.template
```