from contextlib import asynccontextmanager from typing import List, Optional import databases import ormar import sqlalchemy import uvicorn from fastapi import FastAPI DATABASE_URL = "sqlite:///test.db" ormar_base_config = ormar.OrmarConfig( database=databases.Database(DATABASE_URL), metadata=sqlalchemy.MetaData() ) @asynccontextmanager async def lifespan(app: FastAPI): database_ = app.state.database if not database_.is_connected: await database_.connect() yield database_ = app.state.database if database_.is_connected: await database_.disconnect() app = FastAPI(lifespan=lifespan) metadata = sqlalchemy.MetaData() database = databases.Database("sqlite:///test.db") app.state.database = database class Category(ormar.Model): ormar_config = ormar_base_config.copy(tablename="categories") id: int = ormar.Integer(primary_key=True) name: str = ormar.String(max_length=100) class Item(ormar.Model): ormar_config = ormar_base_config.copy(tablename="items") id: int = ormar.Integer(primary_key=True) name: str = ormar.String(max_length=100) category: Optional[Category] = ormar.ForeignKey(Category, nullable=True) @app.get("/items/", response_model=List[Item]) async def get_items(): items = await Item.objects.select_related("category").all() return items @app.post("/items/", response_model=Item) async def create_item(item: Item): await item.save() return item @app.post("/categories/", response_model=Category) async def create_category(category: Category): await category.save() return category @app.put("/items/{item_id}") async def get_item(item_id: int, item: Item): item_db = await Item.objects.get(pk=item_id) return await item_db.update(**item.model_dump()) @app.delete("/items/{item_id}") async def delete_item(item_id: int, item: Item = None): if item: return {"deleted_rows": await item.delete()} item_db = await Item.objects.get(pk=item_id) return {"deleted_rows": await item_db.delete()} if __name__ == "__main__": # to play with API run the script and visit http://127.0.0.1:8000/docs uvicorn.run(app, host="127.0.0.1", port=8000)