## Attribution

# Get Current User

In the previous chapter the security system (which is based on the dependency injection system) was giving the *path operation function* a `token` as a `str`:

//// tab | Python 3.9+

```Python hl_lines="12"
{!> ../../docs_src/security/tutorial001_an_py39.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="11"
{!> ../../docs_src/security/tutorial001_an.py!}
```

////

	expected := false
	if locked != expected {
		t.Errorf("TestDualWriteLockTimedOut(): \nexpected %#v\ngot      %#v", expected, locked)
	}
}

// Test cases below are copied 1 to 1 from sync/rwmutex_test.go (adapted to use LRWMutex)

// Borrowed from rwmutex_test.go
func parallelReader(ctx context.Context, m *LRWMutex, clocked, cunlock, cdone chan bool) {
	if m.GetRLock(ctx, "", "", time.Second) {
		clocked <- true
		<-cunlock

  private var limit = -1L

  /** Type hints scoped to the call stack, manipulated with [withTypeHint]. */
  private val typeHintStack = mutableListOf<Any?>()

  /**
   * The type hint for the current object. Used to pick adapters based on other fields, such as
   * in extensions which have different types depending on their extension ID.
   */
  var typeHint: Any?
    get() = typeHintStack.lastOrNull()
    set(value) {

To see all the options you have, checkout <a href="https://docs.pydantic.dev/latest/concepts/types/" class="external-link" target="_blank">Pydantic's Type Overview</a>. You will see some examples in the next chapter.

For example, as in the `Image` model we have a `url` field, we can declare it to be an instance of Pydantic's `HttpUrl` instead of a `str`:

//// tab | Python 3.10+

```Python hl_lines="2  8"

And that function takes parameters in the same way that *path operation functions* do.

/// tip

You'll see what other "things", apart from functions, can be used as dependencies in the next chapter.

///

Whenever a new request arrives, **FastAPI** will take care of:

* Calling your dependency ("dependable") function with the correct parameters.
* Get the result from your function.

C'est pourquoi, lorsqu'on parle de la version 2.0, il est courant de dire "Swagger", et pour la version 3+ "OpenAPI".

/// check | "A inspiré **FastAPI** à"

Adopter et utiliser une norme ouverte pour les spécifications des API, au lieu d'un schéma personnalisé.

Intégrer des outils d'interface utilisateur basés sur des normes :

Ainsi, votre éditeur vous offrira un support adapté pour l'objet résultant.

Extrait de la documentation officielle de **Pydantic** :

{*../../docs_src/python_types/tutorial011.py*}

/// info

This code is something you can actually use in your application, save the password hashes in your database, etc.

We are going to start from where we left in the previous chapter and increment it.

## About JWT

JWT means "JSON Web Tokens".

It's a standard to codify a JSON object in a long dense string without spaces. It looks like this:

```

    assertThat(decoded.subjectAlternativeNames).isEqualTo(
      Extension(
        id = SUBJECT_ALTERNATIVE_NAME,
        critical = false,
        value =
          listOf(
            Adapters.ANY_VALUE to
              AnyValue(
                tagClass = DerHeader.TAG_CLASS_CONTEXT_SPECIFIC,
                tag = 1L,
                constructed = false,
                length = 16,