If you don't care about any of these terms and you just need to add security with authentication based on username and password *right now*, skip to the next chapters.

## OAuth2

OAuth2 is a specification that defines several ways to handle authentication and authorization.

It is quite an extensive specification and covers several complex use cases.

It includes ways to authenticate using a "third party".

# Parámetros de Cookie

Puedes definir parámetros de Cookie de la misma manera que defines parámetros de `Query` y `Path`.

## Importar `Cookie`

Primero importa `Cookie`:

=== "Python 3.10+"

    ```Python hl_lines="3"
    {!> ../../../docs_src/cookie_params/tutorial001_an_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="3"
    {!> ../../../docs_src/cookie_params/tutorial001_an_py39.py!}
    ```

# Handling Errors

There are many situations in which you need to notify an error to a client that is using your API.

This client could be a browser with a frontend, a code from someone else, an IoT device, etc.

You could need to tell the client that:

* The client doesn't have enough privileges for that operation.
* The client doesn't have access to that resource.
* The item the client was trying to access doesn't exist.
* etc.

The term "schema" might also refer to the shape of some data, like a JSON content.

In that case, it would mean the JSON attributes, and data types they have, etc.

#### OpenAPI and JSON Schema

OpenAPI defines an API schema for your API. And that schema includes definitions (or "schemas") of the data sent and received by your API using **JSON Schema**, the standard for JSON data schemas.

#### Check the `openapi.json`

      entryPoints = ["http"]
      service = "app"
      rule = "PathPrefix(`/api/v1`)"
      middlewares = ["api-stripprefix"]

  [http.services]

    [http.services.app]
      [http.services.app.loadBalancer]
        [[http.services.app.loadBalancer.servers]]
          url = "http://127.0.0.1:8000"
```

This file configures Traefik to use the path prefix `/api/v1`.

Así que esperas a que esa persona 😍 termine la historia (terminas el trabajo actual ⏯ / tarea actual que se está procesando 🤓), sonríes gentilmente y le dices que vas por las hamburguesas ⏸.

    In many cases, OAuth2 with scopes can be an overkill.

    But if you know you need it, or you are curious, keep reading.

## OAuth2 scopes and OpenAPI

The OAuth2 specification defines "scopes" as a list of strings separated by spaces.

The content of each of these strings can have any format, but should not contain spaces.

These scopes represent "permissions".

Each of these attributes represents a column in its corresponding database table.

We use `Column` from SQLAlchemy as the default value.

And we pass a SQLAlchemy class "type", as `Integer`, `String`, and `Boolean`, that defines the type in the database, as an argument.

```Python hl_lines="1  10-13  21-24"
{!../../../docs_src/sql_databases/sql_app/models.py!}
```

### Create the relationships

Now create the relationships.