from fastapi.testclient import TestClient
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: Optional[float] = None
    owner_ids: Optional[List[int]] = None


@app.get("/items/invalid", response_model=Item)
def get_invalid():
    return {"name": "invalid", "price": "foo"}


@app.get("/items/invalidnone", response_model=Item)

@dataclass
class Item:
    name: str
    price: Optional[float] = None
    owner_ids: Optional[List[int]] = None


@app.get("/items/invalid", response_model=Item)
def get_invalid():
    return {"name": "invalid", "price": "foo"}


@app.get("/items/innerinvalid", response_model=Item)
def get_innerinvalid():
    return {"name": "double invalid", "price": "foo", "owner_ids": ["foo", "bar"]}

		{Name: "OwnerID", DBName: "company_owner_id", BindNames: []string{"Base", "OwnerID"}, DataType: schema.Int, Size: 64, TagSettings: map[string]string{"EMBEDDED": "EMBEDDED", "EMBEDDEDPREFIX": "company_"}},
		{Name: "OwnerID", DBName: "owner_id", BindNames: []string{"CorpBase", "OwnerID"}, DataType: schema.String},
	}

	for _, f := range fields {

						FieldSchema: "Toy",
						Polymorphic: Polymorphic{ID: "owner_id", Type: "Type", Value: "users"},
						References: []Reference{
							{ForeignKey: "Type", ForeignSchema: "Toy", PrimaryValue: "users"},
						},
					},
				},
			},
		})
	})

	t.Run("has many", func(t *testing.T) {
		type Toy struct {
			ID        int
			Name      string
			OwnerID   int
			OwnerType string
		}

For example, if you have an app like this:

```Python
from fastapi import FastAPI
from pydantic import BaseModel

class Item(BaseModel):
    name: str
    price: Optional[float] = None
    owner_ids: Optional[List[int]] = None

app = FastAPI()

@app.get("/items/invalidnone", response_model=Item)
def get_invalid_none():
    return None
```

	Number string
}

type Pet struct {
	gorm.Model
	UserID *uint
	Name   string
	Toy    Toy `gorm:"polymorphic:Owner;"`
}

type Toy struct {
	gorm.Model
	Name      string
	OwnerID   string
	OwnerType string
}

type Tools struct {
	gorm.Model
	Name     string
	CustomID string
	Type     string
}

type Company struct {
	ID   int
	Name string
}

`item.dict()`

 & ⤴️ 👥 🚶‍♀️ `dict`'Ⓜ 🔑-💲 👫 🇨🇻 ❌ 🇸🇲 `Item`, ⏮️:

`Item(**item.dict())`

 & ⤴️ 👥 🚶‍♀️ ➕ 🇨🇻 ❌ `owner_id` 👈 🚫 🚚 Pydantic *🏷*, ⏮️:

`Item(**item.dict(), owner_id=user_id)`

///

## 👑 **FastAPI** 📱

& 🔜 📁 `sql_app/main.py` ➡️ 🛠️ & ⚙️ 🌐 🎏 🍕 👥 ✍ ⏭.

### ✍ 💽 🏓

📶 🙃 🌌 ✍ 💽 🏓:

		}
	}

	AssertObjEqual(t, pet, expect, "ID", "CreatedAt", "UpdatedAt", "DeletedAt", "UserID", "Name")

	AssertObjEqual(t, pet.Toy, expect.Toy, "ID", "CreatedAt", "UpdatedAt", "DeletedAt", "Name", "OwnerID", "OwnerType")

	if expect.Toy.Name != "" && expect.Toy.OwnerType != "pets" {
		t.Errorf("toys's OwnerType, expect: %v, got %v", "pets", expect.Toy.OwnerType)
	}
}

func TestJoinsPreload_Issue7013_RelationEmpty(t *testing.T) {
	type (
		Furniture struct {
			gorm.Model
			OwnerID *uint
		}

		Owner struct {
			gorm.Model
			Furnitures []Furniture
			CompanyID  *uint
			Company    Company
		}

		Building struct {
			gorm.Model
			Name    string
			OwnerID *uint
			Owner   Owner
		}
	)

	DB.Migrator().DropTable(&Building{}, &Owner{}, &Furniture{})

这里不是将每个关键字参数传递给Item并从Pydantic模型中读取每个参数，而是先生成一个字典，其中包含Pydantic模型的数据：

`item.dict()`

然后我们将dict的键值对 作为关键字参数传递给 SQLAlchemy `Item`：

`Item(**item.dict())`

然后我们传递 Pydantic模型未提供的额外关键字参数`owner_id`：

`Item(**item.dict(), owner_id=user_id)`

///

## 主**FastAPI**应用程序

现在在`sql_app/main.py`文件中 让我们集成和使用我们之前创建的所有其他部分。

### 创建数据库表

以非常简单的方式创建数据库表：

//// tab | Python 3.9+