from fastapi import FastAPI

app = FastAPI()


@app.get("/items/{item_id}")
async def read_item(item_id):

    tags: list[str] = field(default_factory=list)
    description: Union[str, None] = None
    tax: Union[float, None] = None


app = FastAPI()


@app.get("/item", response_model=Item)
async def read_item():
    return {
        "id": uuid.uuid4(),
        "name": "Island In The Moon",
        "price": 12.99,
        "description": "A place to be be playin' and havin' fun",
        "tags": ["breater"],
    }

from fastapi import FastAPI

app = FastAPI()


@app.get("/items/{item_id}")
async def read_item(item_id: str, q: str | None = None, short: bool = False):
    item = {"item_id": item_id}
    if q:
        item.update({"q": q})
    if not short:
        item.update(
            {"description": "This is an amazing item that has a long description"}
        )

    response_model=Item,
    responses={
        200: {
            "content": {"image/png": {}},
            "description": "Return the JSON item or an image.",
        }
    },
)
async def read_item(item_id: str, img: bool | None = None):
    if img:
        return FileResponse("image.png", media_type="image/png")
    else:

```

### 템플릿 `url_for` 인수

템플릿 내에서 `url_for()`를 사용할 수도 있으며, 이는 *경로 작업 함수*에서 사용될 인수와 동일한 인수를 받습니다.

따라서 다음과 같은 부분에서:

{% raw %}

```jinja
<a href="{{ url_for('read_item', id=id) }}">
```

{% endraw %}

...이는 *경로 작업 함수* `read_item(id=id)`가 처리할 동일한 URL로 링크를 생성합니다.

예를 들어, ID가 `42`일 경우, 이는 다음과 같이 렌더링됩니다:
```html
<a href="/items/42">
```

## 템플릿과 정적 파일

async def validation_exception_handler(request, exc):
    print(f"OMG! The client sent invalid data!: {exc}")
    return await request_validation_exception_handler(request, exc)


@app.get("/items/{item_id}")
async def read_item(item_id: int):
    if item_id == 3:
        raise HTTPException(status_code=418, detail="Nope! I don't like 3.")

    "baz": {"name": "Baz", "description": None, "price": 50.2, "tax": 10.5, "tags": []},
}


@app.get("/items/{item_id}", response_model=Item)
async def read_item(item_id: str):
    return items[item_id]


@app.put("/items/{item_id}", response_model=Item)
async def update_item(item_id: str, item: Item):
    update_item_encoded = jsonable_encoder(item)

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">
<summary>Або використайте <code>async def</code>...</summary>

```Python
from typing import Union

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

<details markdown="1">
<summary>或者使用 <code>async def</code>...</summary>

如果你的代码里会出现 `async` / `await`，请使用 `async def`：

from fastapi.testclient import TestClient
from starlette.exceptions import HTTPException as StarletteHTTPException

app = FastAPI()

items = {"foo": "The Foo Wrestlers"}


@app.get("/items/{item_id}")
async def read_item(item_id: str):
    if item_id not in items:
        raise HTTPException(
            status_code=404,
            detail="Item not found",
            headers={"X-Error": "Some custom header"},
        )