# `UploadFile` class

You can define *path operation function* parameters to be of the type `UploadFile` to receive files from the request.

You can import it directly from `fastapi`:

```python
from fastapi import UploadFile
```

::: fastapi.UploadFile
    options:
        members:
            - file
            - filename
            - size
            - headers
            - content_type
            - read

# `UploadFile`-Klasse

Sie können *Pfadoperation-Funktionsparameter* als Parameter vom Typ `UploadFile` definieren, um Dateien aus dem Request zu erhalten.

Sie können es direkt von `fastapi` importieren:

```python
from fastapi import UploadFile
```

::: fastapi.UploadFile
    options:
        members:
            - file
            - filename
            - size
            - headers
            - content_type

✔️ 🤯 👈 👉 ⛓ 👈 🎂 🎚 🔜 🏪 💾. 👉 🔜 👷 👍 🤪 📁.

✋️ 📤 📚 💼 ❔ 👆 💪 💰 ⚪️➡️ ⚙️ `UploadFile`.

## 📁 🔢 ⏮️ `UploadFile`

🔬 📁 🔢 ⏮️ 🆎 `UploadFile`:

```Python hl_lines="12"
{!../../../docs_src/request_files/tutorial001.py!}
```

⚙️ `UploadFile` ✔️ 📚 📈 🤭 `bytes`:

* 👆 🚫 ✔️ ⚙️ `File()` 🔢 💲 🔢.
* ⚫️ ⚙️ "🧵" 📁:

def test_is_uploadfile_sequence_annotation():
    # For coverage
    # TODO: in theory this would allow declaring types that could be lists of UploadFile
    # and other types, but I'm not even sure it's a good idea to support it as a first
    # class "feature"

                            },
                        },
                    },
                }
            },
            "/uploadfile/": {
                "post": {
                    "summary": "Create Upload File",
                    "operationId": "create_upload_file_uploadfile__post",
                    "requestBody": {
                        "content": {
                            "multipart/form-data": {

이것은 전체 내용이 메모리에 저장된다는 것을 의미한다는 걸 염두하기 바랍니다. 이는 작은 크기의 파일들에 적합합니다.

어떤 경우에는 `UploadFile` 을 사용하는 것이 더 유리합니다.

## `File` 매개변수와  `UploadFile`

`File` 매개변수를 `UploadFile` 타입으로 정의합니다:

```Python hl_lines="12"
{!../../../docs_src/request_files/tutorial001.py!}
```

`UploadFile` 을 사용하는 것은 `bytes` 과 비교해 다음과 같은 장점이 있습니다:

* "스풀 파일"을 사용합니다.
    *  최대 크기 제한까지만 메모리에 저장되며, 이를 초과하는 경우 디스크에 저장됩니다.

from fastapi import FastAPI, File, UploadFile

app = FastAPI()


@app.post("/files/")
async def create_file(file: bytes | None = File(default=None)):
    if not file:
        return {"message": "No file sent"}
    else:
        return {"file_size": len(file)}


@app.post("/uploadfile/")
async def create_upload_file(file: UploadFile | None = None):
    if not file:
        return {"message": "No upload file sent"}
    else:

    ```python
    from typing import Annotated

    from fastapi import FastAPI, File, UploadFile

    app = FastAPI()


    @app.post("/files/")
    async def create_file(file: Annotated[bytes, File()]):
        return {"file_size": len(file)}


    @app.post("/uploadfile/")
    async def create_upload_file(file: UploadFile):
        return {"filename": file.filename}
    ```
    """

    file: Annotated[

from typing import Annotated

from fastapi import FastAPI, File, Form, UploadFile

app = FastAPI()


@app.post("/files/")
async def create_file(
    file: Annotated[bytes, File()],
    fileb: Annotated[UploadFile, File()],
    token: Annotated[str, Form()],
):
    return {
        "file_size": len(file),
        "token": token,
        "fileb_content_type": fileb.content_type,

文件作为「表单数据」上传。

如果把*路径操作函数*参数的类型声明为 `bytes`，**FastAPI** 将以 `bytes` 形式读取和接收文件内容。

这种方式把文件的所有内容都存储在内存里，适用于小型文件。

不过，很多情况下，`UploadFile` 更好用。

## 含 `UploadFile` 的文件参数

定义文件参数时使用 `UploadFile`：

```Python hl_lines="12"
{!../../../docs_src/request_files/tutorial001.py!}
```

`UploadFile` 与 `bytes` 相比有更多优势：

* 使用 `spooled` 文件：
    * 存储在内存的文件超出最大上限时，FastAPI 会把文件存入磁盘；
* 这种方式更适于处理图像、视频、二进制文件等大型文件，好处是不会占用所有内存；