from typing import Union

from fastapi import Body, FastAPI
from pydantic import BaseModel
from typing_extensions import Annotated

app = FastAPI()


class Item(BaseModel):
    name: str
    description: Union[str, None] = None
    price: float
    tax: Union[float, None] = None


class User(BaseModel):
    username: str
    full_name: Union[str, None] = None


@app.put("/items/{item_id}")
async def update_item(

from typing import Annotated, Union

from fastapi import Body, FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: Union[str, None] = None
    price: float
    tax: Union[float, None] = None


class User(BaseModel):
    username: str
    full_name: Union[str, None] = None


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int,

Zum Beispiel deklariert das obige Modell ein JSON "`object`" (oder Python-`dict`) wie dieses:

```JSON
{
    "name": "Foo",
    "description": "An optional description",
    "price": 45.2,
    "tax": 3.5
}
```

Da `description` und `tax` optional sind (mit `None` als Defaultwert), wäre folgendes JSON "`object`" auch gültig:

```JSON
{
    "name": "Foo",
    "price": 45.2
}
```

```

////

与声明查询参数一样，包含默认值的模型属性是可选的，否则就是必选的。默认值为 `None` 的模型属性也是可选的。

例如，上述模型声明如下 JSON **对象**（即 Python **字典**）：

```JSON
{
    "name": "Foo",
    "description": "An optional description",
    "price": 45.2,
    "tax": 3.5
}
```

……由于 `description` 和 `tax` 是可选的（默认值为 `None`），下面的 JSON **对象**也有效：

```JSON
{
    "name": "Foo",
    "price": 45.2
}
```

## 声明请求体参数

        )

    private
    fun findVersionFromJavadoc(javadoc: Javadoc): String? =
        javadoc.blockTags
            .find { tag -> tag.tagName == "since" }
            ?.content?.elements?.find { description -> description is JavadocSnippet }
            ?.toText()

    private
    fun nodeName(it: Node?, unit: CompilationUnit, file: File) = when (it) {

      },
      "createdTime": {
        "type": "long"
      },
      "updatedBy": {
        "type": "keyword"
      },
      "updatedTime": {
        "type": "long"
      },
      "description" : {
        "type": "text",
        "analyzer": "standard_analyzer"
      }
    }

from typing import Union

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: Union[str, None] = None
    price: float
    tax: Union[float, None] = None
    tags: set[str] = set()


@app.post("/items/", response_model=Item, tags=["items"])
async def create_item(item: Item):
    return item


@app.get("/items/", tags=["items"])

import model.CIBuildModel
import model.Stage

class SanityCheck(model: CIBuildModel, stage: Stage) : OsAwareBaseGradleBuildType(os = Os.LINUX, stage = stage, init = {
    id(buildTypeId(model))
    name = "Sanity Check"
    description = "Static code analysis, checkstyle, release notes verification, etc."

    features {
        publishBuildStatusToGithub(model)
    }

    applyDefaults(
        model,
        this,
        "sanityCheck",

 * based on these entries.
 * <p>
 * To fully understand the information exposed by this class a description
 * of the access check algorithm used by Windows is required. The following
 * is a basic description of the algorithm. For a more complete description
 * we recommend reading the section on Access Control in Keith Brown's
 * "The .NET Developer's Guide to Windows Security" (which is also

Например, модель выше описывает вот такой JSON "объект" (или словарь Python):

```JSON
{
    "name": "Foo",
    "description": "An optional description",
    "price": 45.2,
    "tax": 3.5
}
```

...поскольку `description` и `tax` являются необязательными (с `None` в качестве значения по умолчанию), вот такой JSON "объект" также подходит:

```JSON
{
    "name": "Foo",