## FastAPI Experts

These are the users that have been [helping others the most with questions in GitHub](help-fastapi.md#help-others-with-questions-in-github). 🙇

They have proven to be **FastAPI Experts** by helping many others. ✨

/// tip

        assertEquals("others", fileTypeHelper.get("non/existent"));
    }

    @Test
    public void test_get_withNullMimetype() {
        assertEquals("others", fileTypeHelper.get(null));
    }

    @Test
    public void test_get_withEmptyMimetype() {
        assertEquals("others", fileTypeHelper.get(""));
        assertEquals("others", fileTypeHelper.get(" "));
    }

    @Test

/// note | Technical Details

Actually, `Query`, `Path` and others you'll see next create objects of subclasses of a common `Param` class, which is itself a subclass of Pydantic's `FieldInfo` class.

And Pydantic's `Field` returns an instance of `FieldInfo` as well.

`Body` also returns objects of a subclass of `FieldInfo` directly. And there are others you will see later that are subclasses of the `Body` class.

* [Vote for **FastAPI** in AlternativeTo](https://alternativeto.net/software/fastapi/about/).
* [Say you use **FastAPI** on StackShare](https://stackshare.io/pypi-fastapi).

## Help others with questions in GitHub { #help-others-with-questions-in-github }

You can try and help others with their questions in:

* [GitHub Discussions](https://github.com/fastapi/fastapi/discussions/categories/questions?discussions_q=category%3AQuestions+is%3Aunanswered)

   capacity and competence.

 * **Be considerate**: People use our work, and we depend on the work of others. Consider users and
   colleagues before taking action. For example, changes to code, infrastructure, policy, and
   documentation may negatively impact others.

 * **Be respectful**: We expect people to work together to resolve conflict, assume good intentions,

# Including WSGI - Flask, Django, others { #including-wsgi-flask-django-others }

You can mount WSGI applications as you saw with [Sub Applications - Mounts](sub-applications.md), [Behind a Proxy](behind-a-proxy.md).

For that, you can use the `WSGIMiddleware` and use it to wrap your WSGI application, for example, Flask, Django, etc.

## Using `WSGIMiddleware` { #using-wsgimiddleware }

/// info

        That's a lot of work they are doing, but if more FastAPI users came to help others like them just a little bit more, it would be much less effort for them (and you and me 😅).

* `le`: `l`ess than or `e`qual

/// info

`Query`, `Path`, and other classes you will see later are subclasses of a common `Param` class.

All of them share the same parameters for additional validation and metadata you have seen.

///

/// note | Technical Details

When you import `Query`, `Path` and others from `fastapi`, they are actually functions.

# Custom Response Classes - File, HTML, Redirect, Streaming, etc.

There are several custom response classes you can use to create an instance and return them directly from your *path operations*.

Read more about it in the [FastAPI docs for Custom Response - HTML, Stream, File, others](https://fastapi.tiangolo.com/advanced/custom-response/).

You can import them directly from `fastapi.responses`:

```python
from fastapi.responses import (
    FileResponse,

/*
 * Copyright 2012-2025 CodeLibs Project and the Others.
 *
 * 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,