Now you can replace the `.openapi()` method with your new function.

{* ../../docs_src/extending_openapi/tutorial001.py hl[29] *}

### Check it { #check-it }

Once you go to <a href="http://127.0.0.1:8000/redoc" class="external-link" target="_blank">http://127.0.0.1:8000/redoc</a> you will see that you are using your custom logo (in this example, **FastAPI**'s logo):

 *
 * 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,

 * Copyright (C) 2016 Square, Inc.
 *
 * 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,

import okhttp3.internal.publicsuffix.PublicSuffixDatabase

/**
 * [DNS over HTTPS implementation][doh_spec].
 *
 * > A DNS API client encodes a single DNS query into an HTTP request
 * > using either the HTTP GET or POST method and the other requirements
 * > of this section.  The DNS API server defines the URI used by the
 * > request through the use of a URI Template.
 *

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//DBFLUTE//DTD LastaDi 1.0//EN" 
	"http://dbflute.org/meta/lastadi10.dtd">
<components>
    <include path="crawler_opensearch.xml"/>

/*
 * Copyright (C) 2010 The Guava Authors
 *
 * 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

Если вы хотите узнать больше про кодировки и поля формы, ознакомьтесь с <a href="https://developer.mozilla.org/ru/docs/Web/HTTP/Methods/POST" class="external-link" target="_blank">документацией <abbr title="Mozilla Developer Network">MDN</abbr> для `POST` на веб-сайте</a>.

///

/// warning | Предупреждение

Якщо Ви хочете дізнатися більше про ці кодування та поля форм, зверніться до <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/POST" class="external-link" target="_blank"><abbr title="Mozilla Developer Network">MDN</abbr> вебдокументації для <code>POST</code></a>.

///

/// warning | Попередження

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//DBFLUTE//DTD LastaDi 1.0//EN"
	"http://dbflute.org/meta/lastadi10.dtd">
<components namespace="fessCrawler">
	<include path="crawler/transformer_basic.xml"/>

Якщо були заплановані фонові задачі (background tasks - розглянуто далі), вони виконаються *після* всіх middleware.

///

## Створення middleware

Щоб створити middleware, Ви використовуєте декоратор `@app.middleware("http")` на функції.

Функція middleware отримує:

* `Запит`.
* Функцію `call_next`, яка приймає `запит` як параметр.
    * Ця функція передає `запит` відповідній *операції шляху*.