public static final String FEATURE_SECURE_PROCESSING = "http://javax.xml.XMLConstants/feature/secure-processing";

    public static final String FEATURE_EXTERNAL_GENERAL_ENTITIES = "http://xml.org/sax/features/external-general-entities";

    public static final String FEATURE_EXTERNAL_PARAMETER_ENTITIES = "http://xml.org/sax/features/external-parameter-entities";

    private Constants() {
    }

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.1.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.1.0 https://maven.apache.org/xsd/maven-4.1.0.xsd">
    <modelVersion>4.1.0</modelVersion>

    <groupId>test</groupId>
    <artifactId>test</artifactId>
    <version>0.1-SNAPSHOT</version>

    <dependencyManagement>
        <dependencies>

specific language governing permissions and limitations
under the License.
-->

<model xmlns="http://codehaus-plexus.github.io/MODELLO/2.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://codehaus-plexus.github.io/MODELLO/2.0.0 https://codehaus-plexus.github.io/modello/xsd/modello-2.0.0.xsd"
  xml.namespace="http://maven.apache.org/METADATA/${version}"

 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,

		if opts.Maintenance {
			writeResponse(w, http.StatusPreconditionFailed, nil, mimeNone)
		} else {
			writeResponse(w, http.StatusServiceUnavailable, nil, mimeNone)
		}
		return
	}
	writeResponse(w, http.StatusOK, nil, mimeNone)
}

// ClusterReadCheckHandler returns if the server is ready for requests.
func ClusterReadCheckHandler(w http.ResponseWriter, r *http.Request) {
	ctx := newContext(r, w, "ClusterReadCheckHandler")

この例を実行し、ブラウザで <a href="http://127.0.0.1:8000/items/3" class="external-link" target="_blank">http://127.0.0.1:8000/items/3</a> を開くと、次のレスポンスが表示されます:

```JSON
{"item_id":3}
```

/// check | "確認"

関数が受け取った（および返した）値は、文字列の `"3"` ではなく、Pythonの `int` としての `3` であることに注意してください。

したがって、型宣言を使用すると、**FastAPI**は自動リクエスト <abbr title="HTTPリクエストで受け取った文字列をPythonデータへ変換する">"解析"</abbr> を行います。

///

需要向客户端返回错误提示的场景主要如下：

- 客户端没有执行操作的权限
- 客户端没有访问资源的权限
- 客户端要访问的项目不存在
- 等等 ...

遇到这些情况时，通常要返回 **4XX**（400 至 499）**HTTP 状态码**。

**4XX** 状态码与表示请求成功的 **2XX**（200 至 299） HTTP 状态码类似。

只不过，**4XX** 状态码表示客户端发生的错误。

大家都知道**「404 Not Found」**错误，还有调侃这个错误的笑话吧？

## 使用 `HTTPException`

向客户端返回 HTTP 错误响应，可以使用 `HTTPException`。

### 导入 `HTTPException`

```Python hl_lines="1"
{!../../docs_src/handling_errors/tutorial001.py!}

<div class="termy">

```console
$ uvicorn main:app --reload

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

E abra a documentação em <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

time="2020-07-12T20:45:50Z" level=info msg="config id tokens valid for: 3h0m0s"
time="2020-07-12T20:45:50Z" level=info msg="listening (http) on 0.0.0.0:5556"
```

### Configure MinIO server with Dex

```
~ export MINIO_IDENTITY_OPENID_CLAIM_NAME=name
~ export MINIO_IDENTITY_OPENID_CONFIG_URL=http://127.0.0.1:5556/dex/.well-known/openid-configuration
~ minio server ~/test
```

### Run the `web-identity.go`

```

trainer.aero
union.aero
workinggroup.aero
works.aero

// af : http://www.nic.af/help.jsp
af
gov.af
com.af
org.af
net.af
edu.af

// ag : http://www.nic.ag/prices.htm
ag
com.ag
org.ag
net.ag
co.ag
nom.ag

// ai : http://nic.com.ai/
ai
off.ai
com.ai
net.ai
org.ai

// al : http://www.ert.gov.al/ert_alb/faq_det.html?Id=31
al
com.al
edu.al