## Executando na inicialização

Na maioria dos casos, quando você cria uma API web, você quer que ela esteja **sempre em execução**, ininterrupta, para que seus clientes possam sempre acessá-la. Isso é claro, a menos que você tenha um motivo específico para querer que ela seja executada somente em certas situações, mas na maioria das vezes você quer que ela esteja constantemente em execução e **disponível**.

### Em um servidor remoto

E quando a dependência for resolvida, o **FastAPI** chamará este `checker` como:

```Python
checker(q="somequery")
```

...e passar o que quer que isso retorne como valor da dependência em nossa *função de operação de rota* como o parâmetro `fixed_content_included`:

//// tab | Python 3.9+

```Python hl_lines="22"

labels.num	=	Numéro
labels.pn	=	Numéro de page
labels.protocolScheme	=	Schème
labels.purgeByBots	=	Purge par les bots
labels.logLevel	=	Niveau de journalisation
labels.purgeSearchLogDay	=	Purger le journal de recherche
labels.query	=	Requête
labels.queryId	=	ID de requête
labels.rt	=	rt
labels.searchLog	=	Journal de recherche
labels.sort	=	Trier
labels.start	=	Point de départ
labels.loginRequired	=	Connexion requise

  // webhook, for example, a cluster identifier.
  //
  // Attempting to use a user or basic auth e.g. "user:password@" is not
  // allowed. Fragments ("#...") and query parameters ("?...") are not
  // allowed, either.
  //
  // +optional
  optional string url = 3;

  // `service` is a reference to the service for this webhook. Either
  // `service` or `url` must be specified.

* HTTP Basic.
* **OAuth2** (với **JWT tokens**). Xem hướng dẫn [OAuth2 with JWT](tutorial/security/oauth2-jwt.md){.internal-link target=_blank}.
* API keys in:
    * Headers.
    * Các tham số trong query string.
    * Cookies, etc.

Cộng với tất cả các tính năng bảo mật từ Starlette (bao gồm **session cookies**).

                this.fileLocator.updateType(response.getFileType());
                info = response;
                fileSize = response.getDataSize();

                // this is so damn unreliable, needs another race-prone query if required
                haveAttributes = false;

                // This seems to be the only way to obtain a reliable (with respect to locking) file size here

* the contents of a file in the disk to be read by the system and given to your program
* the contents your program gave to the system to be written to disk
* a remote API operation
* a database operation to finish
* a database query to return the results
* etc.

As the execution time is consumed mostly by waiting for <abbr title="Input and Output">I/O</abbr> operations, they call them "I/O bound" operations.

    }

    @Override
    public void add(@ParametricNullness V value) {
      previous = addNode(key, value, next);
      nextIndex++;
      current = null;
    }
  }

  // Query Operations

  @Override
  public int size() {
    return size;
  }

  @Override
  public boolean isEmpty() {
    return head == null;
  }

  @Override

    resolve_symlinks: (Bool) Translate symbolic links into the real filepath.
    n_ask_attempts: (Integer) Number of times to query for valid input before
      raising an error and quitting.

  Returns:
    [String] The value of var_name after querying for input.

  Raises:
    UserInputError: if a query has been attempted n_ask_attempts times without
      success, assume that the user has made a scripting error, and will

But by using `Security` instead of `Depends`, **FastAPI** will know that it can declare security scopes, use them internally, and document the API with OpenAPI.

But when you import `Query`, `Path`, `Depends`, `Security` and others from `fastapi`, those are actually functions that return special classes.

///

## Use `SecurityScopes`

Now update the dependency `get_current_user`.