<outputFilename>maven-skinny-bom.xml</outputFilename>
              <reactorDependencies>REACTOR</reactorDependencies>
              <transitiveDependencies>NONE</transitiveDependencies>
              <usePropertiesForVersion>true</usePropertiesForVersion>
              <attach>true</attach>
            </configuration>
          </execution>
          <execution>

///

## Optional File Upload { #optional-file-upload }

You can make a file optional by using standard type annotations and setting a default value of `None`:

{* ../../docs_src/request_files/tutorial001_02_an_py310.py hl[9,17] *}

## `UploadFile` with Additional Metadata { #uploadfile-with-additional-metadata }

/// note

- 请注意，您必须直接使用 `FileResponse` 返回图像。

///

/// info

- 除非在 `responses` 参数中明确指定不同的媒体类型，否则**FastAPI**将假定响应与主响应类具有相同的媒体类型（默认为` application/json` ）。
- 但是如果您指定了一个自定义响应类，并将 `None `作为其媒体类型，**FastAPI**将使用 `application/json` 作为具有关联模型的任何其他响应。

///

## 组合信息
您还可以联合接收来自多个位置的响应信息，包括 `response_model `、 `status_code` 和 `responses `参数。

Isso não é uma limitação do **FastAPI**, é parte do protocolo HTTP.

///

## Upload de Arquivo Opcional

Você pode tornar um arquivo opcional usando anotações de tipo padrão e definindo um valor padrão de `None`:

{* ../../docs_src/request_files/tutorial001_02_an_py310.py hl[9,17] *}

## `UploadFile` com Metadados Adicionais

Você também pode usar `File()` com `UploadFile`, por exemplo, para definir metadados adicionais:

```

/// tip

آرگومان دوم <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> مقدار پیش‌فرضیه که برمی‌گردونه.

اگه ندی، به‌صورت پیش‌فرض `None` هست، اینجا ما `"World"` رو به‌عنوان مقدار پیش‌فرض گذاشتیم.

///

بعد می‌تونی اون برنامه پایتون رو صدا کنی:

//// tab | لینوکس، مک‌اواس، ویندوز بش

<div class="termy">

```console

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: Optional[str] = None):
    return {"item_id": item_id, "q": q}
```

* Vous devriez maintenant avoir une structure de répertoire telle que :

```
.
├── app
│   └── main.py
└── Dockerfile
```

     * @return the algorithm name
     */
    public static String getAlgorithmName(int algorithm) {
        switch (algorithm) {
        case COMPRESSION_NONE:
            return "None";
        case COMPRESSION_LZ77:
            return "LZ77";
        case COMPRESSION_LZ77_HUFFMAN:
            return "LZ77+Huffman";
        case COMPRESSION_LZNT1:
            return "LZNT1";

        sb.append("       id: ").append(getId()).append('\n');
        sb.append("      url: ").append(getUrl()).append('\n');
        sb.append("   layout: ").append(layout != null ? layout : "none").append('\n');

        if (snapshots != null) {
            sb.append("snapshots: [enabled => ").append(snapshots.isEnabled());
            sb.append(", update => ").append(snapshots.getUpdatePolicy()).append("]\n");

     *
     * @param key the key for which to retrieve the session data, must not be {@code null}
     * @return the session data associated with the key or {@code null} if none
     */
    @Nullable
    <T> T get(@Nonnull Key<T> key);

    /**
     * Retrieve of compute the data associated with the specified key.
     *

    }

    @Test
    @DisplayName("Test algorithm names")
    public void testAlgorithmNames() {
        assertEquals("None", compressionService.getAlgorithmName(CompressionService.COMPRESSION_NONE));
        assertEquals("LZ77", compressionService.getAlgorithmName(CompressionService.COMPRESSION_LZ77));