import * as fs from 'fs'

async function modifyOpenAPIFile(filePath) {
  try {
    const data = await fs.promises.readFile(filePath)
    const openapiContent = JSON.parse(data)

    const paths = openapiContent.paths
    for (const pathKey of Object.keys(paths)) {
      const pathData = paths[pathKey]
      for (const method of Object.keys(pathData)) {
        const operation = pathData[method]
        if (operation.tags && operation.tags.length > 0) {

```JSON
{
    "message": "Hello World",
    "root_path": "/api/v1"
}
```

### Setting the `root_path` in the FastAPI app

Alternatively, if you don't have a way to provide a command line option like `--root-path` or equivalent, you can set the `root_path` parameter when creating your FastAPI app:

```Python hl_lines="3"
{!../../../docs_src/behind_a_proxy/tutorial002.py!}
```

                ```python
                "items:read items:write users:read profile openid"
                ````

                would represent the scopes:

                * `items:read`
                * `items:write`
                * `users:read`
                * `profile`
                * `openid`
                """
            ),
        ] = "",

These features are what Marshmallow was built to provide. It is a great library, and I have used it a lot before.

But it was created before there existed Python type hints. So, to define every <abbr title="the definition of how data should be formed">schema</abbr> you need to use specific utils and classes provided by Marshmallow.

!!! check "Inspired **FastAPI** to"
    Use code to define "schemas" that provide data types and validation, automatically.

    hashed_password: str


def get_user(db, username: str):
    if username in db:
        user_dict = db[username]
        return UserInDB(**user_dict)


def fake_decode_token(token):
    # This doesn't provide any security at all
    # Check the next version
    user = get_user(fake_users_db, token)
    return user


async def get_current_user(token: Annotated[str, Depends(oauth2_scheme)]):

* <a href="https://tartiflette.io/" class="external-link" target="_blank">Tartiflette</a>
    * With <a href="https://tartiflette.github.io/tartiflette-asgi/" class="external-link" target="_blank">Tartiflette ASGI</a> to provide ASGI integration
* <a href="https://graphene-python.org/" class="external-link" target="_blank">Graphene</a>

And it shows their true commitment to FastAPI and its **community** (you), as they not only want to provide you a **good service** but also want to make sure you have a **good and healthy framework**, FastAPI. 🙇

			}
        }
    }

    /**
     * Helper function for animation delays, called with `await`.
     * @param {number} time - Timeout, in ms.
     */
    _wait(time) {
        return new Promise(resolve => setTimeout(resolve, time));
    }

    /**
     * Converts line data objects into line elements.
     *
     * @param {Object[]} lineData - Dynamically loaded lines.

!!! tip "Dica"
    O `shutdown` aconteceria quando você estivesse **encerrando** a aplicação.

    Talvez você precise inicializar uma nova versão, ou apenas cansou de executá-la. 🤷

### Função _lifespan_

A primeira coisa a notar, é que estamos definindo uma função assíncrona com `yield`. Isso é muito semelhante à Dependências com `yield`.

Há diversas situações em que você precisa notificar um erro a um cliente que está utilizando a sua API.

Esse cliente pode ser um browser com um frontend, o código de outra pessoa, um dispositivo IoT, etc.

Pode ser que você precise comunicar ao cliente que:

* O cliente não tem direitos para realizar aquela operação.
* O cliente não tem acesso aquele recurso.
* O item que o cliente está tentando acessar não existe.
* etc.