};\n\n    // init state\n    this.state = {\n      isDestroyed: false,\n      isCreated: false,\n      scrollParents: [],\n    };\n\n    // get reference and popper elements (allow jQuery wrappers)\n    this.reference = reference && reference.jquery ? reference[0] : reference;\n    this.popper = popper && popper.jquery ? popper[0] : popper;\n\n    // Deep merge modifiers options\n    this.options.modifiers = {};\n    Object.keys({\n      ...Popper.Defaults.modifiers,\n      ...options.modifiers,\n...

  // 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

Nesse caso, você poderia querer documentar como essa API externa *deveria* ser. Que *operação de rota* ela deveria ter, que corpo ela deveria esperar, que resposta ela deveria retornar, etc.

## Um aplicativo com callbacks

Vamos ver tudo isso com um exemplo.

* 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`.

Neste exemplo, usaremos **SQLite**, porque ele usa um único arquivo e o Python tem suporte integrado. Assim, você pode copiar este exemplo e executá-lo como está.

Mais tarde, para sua aplicação em produção, você pode querer usar um servidor de banco de dados como o **PostgreSQL**.

/// tip | Dica