schemas: Optional[Dict[str, Union[Schema, Reference]]] = None
    responses: Optional[Dict[str, Union[Response, Reference]]] = None
    parameters: Optional[Dict[str, Union[Parameter, Reference]]] = None
    examples: Optional[Dict[str, Union[Example, Reference]]] = None
    requestBodies: Optional[Dict[str, Union[RequestBody, Reference]]] = None
    headers: Optional[Dict[str, Union[Header, Reference]]] = None

Each section gradually builds on the previous ones, but it's structured to separate topics, so that you can go directly to any specific one to solve your specific API needs.

It is also built to work as a future reference.

So you can come back and see exactly what you need.

## Run the code

All the code blocks can be copied and used directly (they are actually tested Python files).

    - how-to/nosql-databases-couchbase.md
- Reference (Code API):
  - reference/index.md
  - reference/fastapi.md
  - reference/parameters.md
  - reference/status.md
  - reference/uploadfile.md
  - reference/exceptions.md
  - reference/dependencies.md
  - reference/apirouter.md
  - reference/background.md
  - reference/request.md
  - reference/websockets.md
  - reference/httpconnection.md
  - reference/response.md

            * A key `schema`, that has as the value the JSON Schema from the model, here's the correct place.
                * **FastAPI** adds a reference here to the global JSON Schemas in another place in your OpenAPI instead of including it directly. This way, other applications and clients can use those JSON Schemas directly, provide better code generation tools, etc.

# Dependencies - `Depends()` and `Security()`

## `Depends()`

Dependencies are handled mainly with the special function `Depends()` that takes a callable.

Here is the reference for it and its parameters.

You can import it directly from `fastapi`:

```python
from fastapi import Depends
```

::: fastapi.Depends

## `Security()`

You should see a very long JavaScript file for **ReDoc**.

It could start with something like:

```JavaScript
/*!
 * ReDoc - OpenAPI/Swagger-generated API Reference Documentation
 * -------------------------------------------------------------
 *   Version: "2.0.0-rc.18"
 *   Repo: https://github.com/Redocly/redoc
 */
!function(e,t){"object"==typeof exports&&"object"==typeof m

# Request Parameters

Here's the reference information for the request parameters.

These are the special functions that you can put in *path operation function* parameters or dependency functions with `Annotated` to get data from the request.

It includes:

* `Query()`
* `Path()`
* `Body()`
* `Cookie()`
* `Header()`
* `Form()`
* `File()`

You can import them all directly from `fastapi`:

```python

!!! warning
    This is, more or less, an "advanced" idea.

    If you are just starting with **FastAPI** you might want to skip it for now.

In Python, you can create Context Managers by <a href="https://docs.python.org/3/reference/datamodel.html#context-managers" class="external-link" target="_blank">creating a class with two methods: `__enter__()` and `__exit__()`</a>.

You can also use them inside of **FastAPI** dependencies with `yield` by using

# `APIRouter` class

Here's the reference information for the `APIRouter` class, with all its parameters, attributes and methods.

You can import the `APIRouter` class directly from `fastapi`:

```python
from fastapi import APIRouter
```

::: fastapi.APIRouter
    options:
        members:
            - websocket
            - include_router
            - get
            - put
            - post
            - delete

# `FastAPI` class

Here's the reference information for the `FastAPI` class, with all its parameters, attributes and methods.

You can import the `FastAPI` class directly from `fastapi`:

```python
from fastapi import FastAPI
```

::: fastapi.FastAPI
    options:
        members:
            - openapi_version
            - webhooks
            - state
            - dependency_overrides
            - openapi