dibang-xiaoshou/backend

Backend (FastAPI)

This service exposes the HTTP + WebSocket APIs and database access required by the weighbridge system. It targets Python 3.11+.

Quickstart

cd /Users/wuzilong/work/00code/simple-dibang-xiaoshou/backend
python -m venv .venv
source .venv/bin/activate  # Windows: .venv\Scripts\activate
pip install -U pip uv
uv pip install -e ".[dev]"
uv run fastapi dev app/main.py  # auto reload server

Layout

• app/main.py – FastAPI application entrypoint.
• app/core/config.py – environment-driven settings.
• app/db/session.py – SQLModel engine/session helpers.
• app/api/routes – routers grouped by bounded context.
• app/services – business logic (batch number generation, printing jobs, etc.).
• tests/ – pytest suites (API, domain, migrations).

Environment

Copy .env.example to .env and adjust values for your environment.

Required Variables

Variable	Description	Example
DATABASE_URL	MySQL database connection string	mysql+asyncmy://user:pass@localhost:3306/dibang?charset=utf8mb4
JWT_SECRET	HS256 secret for signing JWTs (must be strong in production)	your-strong-secret-key-here

Optional Variables

Variable	Description	Default
ENV	Environment: dev, test, or prod	dev
ACCESS_TOKEN_EXPIRES_MINUTES	Access token expiration time (minutes)	60
REFRESH_TOKEN_EXPIRES_DAYS	Refresh token expiration time (days)	14
HOST	Server bind address	0.0.0.0
PORT	Server port	8000
CORS_ORIGINS	Allowed CORS origins (comma-separated, use * for all)	*
CORS_ALLOW_CREDENTIALS	Allow credentials in CORS	true
CORS_ALLOW_METHODS	Allowed HTTP methods (comma-separated, use * for all)	*
CORS_ALLOW_HEADERS	Allowed HTTP headers (comma-separated, use * for all)	*
DB_POOL_SIZE	Database connection pool size	10
DB_MAX_OVERFLOW	Max overflow connections	20
DB_POOL_TIMEOUT	Connection pool timeout (seconds)	30
DB_POOL_RECYCLE	Connection recycle time (seconds)	3600
DB_POOL_PRE_PING	Enable connection pre-ping	true

See env.example for detailed comments and examples.

Tooling

• Lint/format: ruff check app, ruff format app.
• Type check: mypy app.
• Tests: pytest.
• Migrations: alembic revision --autogenerate -m "<msg>".

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The scaffold follows the architecture plan in frontend_backend_framework_plan.md, making it easy to plug into the new PC and mobile frontends.