```JSON
{
  "detail": "Item not found"
}
```

/// tip

When raising an `HTTPException`, you can pass any value that can be converted to JSON as the parameter `detail`, not only `str`.

You could pass a `dict`, a `list`, etc.

They are handled automatically by **FastAPI** and converted to JSON.

///

## Add custom headers { #add-custom-headers }

The following commands set a local alias, validate the server information, create a bucket, copy data to that bucket, and list the contents of the bucket.

```sh
mc alias set local http://localhost:9000 minioadmin minioadmin
mc admin info
mc mb data
mc cp ~/Downloads/mydata data/
mc ls data/
```

	otags := &objectTagging{
		TagSet: &ObjectTagSet{},
	}

	var list []tags.Tag
	for k, v := range ot.ToMap() {
		list = append(list, tags.Tag{
			Key:   k,
			Value: v,
		})
	}
	// Always return in sorted order for tags.
	sort.Slice(list, func(i, j int) bool {
		return list[i].Key < list[j].Key
	})
	otags.TagSet.Tags = list

	writeSuccessResponseXML(w, encodeResponse(otags))
}

                rpc.names.names = new lsarpc.LsarTranslatedName[1];
                rpc.names.names[0] = new lsarpc.LsarTranslatedName();
                rpc.names.names[0].sid_type = (short) jcifs.SID.SID_TYPE_UNKNOWN; // not in switch list
                rpc.names.names[0].name = new UnicodeString("unknown", false);
                rpc.names.names[0].sid_index = 0;
                return null;
            }).when(handle).sendrecv(any());

```JSON
{
  "detail": "Item not found"
}

```

/// tip | 提示

触发 `HTTPException` 时，可以用参数 `detail` 传递任何能转换为 JSON 的值，不仅限于 `str`。

还支持传递 `dict`、`list` 等数据结构。

**FastAPI** 能自动处理这些数据，并将之转换为 JSON。

///

## 添加自定义响应头

有些场景下要为 HTTP 错误添加自定义响应头。例如，出于某些方面的安全需要。

一般情况下可能不会需要在代码中直接使用响应头。

但对于某些高级应用场景，还是需要添加自定义响应头：

            "*\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000";

    /**
     * This is a special name for querying the master browser that serves the
     * list of hosts found in "Network Neighborhood".
     */

    public static final String MASTER_BROWSER_NAME = "\u0001\u0002__MSBROWSE__\u0002";

    /**

        // Then
        assertEquals(0, request.getCapabilities() & Smb2Constants.SMB2_GLOBAL_CAP_ENCRYPTION);
    }

    @Test
    @DisplayName("Should generate correct dialect list")
    void testDialectGeneration() {
        // Given
        when(mockConfig.getMinimumVersion()).thenReturn(DialectVersion.SMB210);
        when(mockConfig.getMaximumVersion()).thenReturn(DialectVersion.SMB311);

     * addValue()} methods, is not significant.
     *
     * <p><b>Note:</b> in general, code should assume that the string form returned by {@code
     * ToStringHelper} for a given object may change. In particular, the list of types which are
     * checked for emptiness is subject to change. We currently check {@code CharSequence}s, {@code
     * Collection}s, {@code Map}s, optionals (including Guava's), and arrays.
     *
     * @since 33.4.0

     * Test <a href="https://issues.apache.org/jira/browse/MNG-5568">MNG-5568</a> edge case
     * which was showing transitive inconsistency: since A &gt; B and B &gt; C then we should have A &gt; C
     * otherwise sorting a list of ComparableVersions() will in some cases throw runtime exception;
     * see Netbeans issues <a href="https://netbeans.org/bugzilla/show_bug.cgi?id=240845">240845</a> and

/// note

如果你不知道差別，請查看 [Async: *"In a hurry?"*](../async.md#in-a-hurry){.internal-link target=_blank}.

///

### 第五步：回傳內容

{* ../../docs_src/first_steps/tutorial001.py h1[8] *}

你可以返回一個 `dict`、`list`、單個值作為 `str`、`int` 等。

你也可以返回 Pydantic 模型（稍後你會看到更多關於這方面的內容）。

有很多其他物件和模型會自動轉換為 JSON（包括 ORMs，等等）。試用你最喜歡的，很有可能它們已經有支援。

## 回顧

* 引入 `FastAPI`.
* 建立一個 `app` 實例。