## ✨ Features

### Core Utilities
- **Bean Manipulation** (`org.codelibs.core.beans`) - JavaBeans metadata handling, property access, and object conversion with comprehensive `BeanDesc` system
- **Type Conversion** (`org.codelibs.core.convert`) - Comprehensive utilities for converting between Java types with null-safe operations and support for all primitive types

///

/// info

To declare headers, you need to use `Header`, because otherwise the parameters would be interpreted as query parameters.

///

## Automatic conversion { #automatic-conversion }

`Header` has a little extra functionality on top of what `Path`, `Query` and `Cookie` provide.

Most of the standard headers are separated by a "hyphen" character, also known as the "minus symbol" (`-`).

* `int`
* `float`
* `str`
* `bool`

But you can also use more complex data types.

And you will still have the same features as seen up to now:

* Great editor support.
* Data conversion from incoming requests.
* Data conversion for response data.
* Data validation.
* Automatic annotation and documentation.

## Other data types { #other-data-types }

Here are some of the additional data types you can use:

/// tip

`JSONResponse` itself is a sub-class of `Response`.

///

And when you return a `Response`, **FastAPI** will pass it directly.

It won't do any data conversion with Pydantic models, it won't convert the contents to any type, etc.

This gives you a lot of flexibility. You can return any data type, override any data declaration or validation, etc.

        "name": "The Foo live"
    }
}
```

Again, doing just that declaration, with **FastAPI** you get:

* Editor support (completion, etc.), even for nested models
* Data conversion
* Data validation
* Automatic documentation

## Special types and validation { #special-types-and-validation }

/// check

Also notice that **FastAPI** is smart enough to notice that the path parameter `item_id` is a path parameter and `q` is not, so, it's a query parameter.

///

## Query parameter type conversion { #query-parameter-type-conversion }

You can also declare `bool` types, and they will be converted:

{* ../../docs_src/query_params/tutorial003_py310.py hl[7] *}

In this case, if you go to:

```

/// check

This will give you editor support inside of your function, with error checks, completion, etc.

///

## Data <abbr title="also known as: serialization, parsing, marshalling">conversion</abbr> { #data-conversion }

If you run this example and open your browser at <a href="http://127.0.0.1:8000/items/3" class="external-link" target="_blank">http://127.0.0.1:8000/items/3</a>, you will see a response of:

```JSON

For example, if you have a header parameter `save_data` in the code, the expected HTTP header will be `save-data`, and it will show up like that in the docs.

If for some reason you need to disable this automatic conversion, you can do it as well for Pydantic models for header parameters.

{* ../../docs_src/header_param_models/tutorial003_an_py310.py hl[19] *}

/// warning

/// check | Revisa

Además, nota que **FastAPI** es lo suficientemente inteligente para notar que el parámetro de path `item_id` es un parámetro de path y `q` no lo es, por lo tanto, es un parámetro de query.

///

## Conversión de tipos en parámetros de query

También puedes declarar tipos `bool`, y serán convertidos:

{* ../../docs_src/query_params/tutorial003_py310.py hl[7] *}

En este caso, si vas a:

```

    }
}
```

/// note

Notice that even though the `item` was declared the same way as before, it is now expected to be inside of the body with a key `item`.

///

**FastAPI** will do the automatic conversion from the request, so that the parameter `item` receives its specific content and the same for `user`.

It will perform the validation of the compound data, and will document it like that for the OpenAPI schema and automatic docs.