/// 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.
* Assign that result to the parameter in your *path operation function*.

```

/// check

Notice that the value your function received (and returned) is `3`, as a Python `int`, not a string `"3"`.

So, with that type declaration, **FastAPI** gives you automatic request <abbr title="converting the string that comes from an HTTP request into Python data">"parsing"</abbr>.

///

## Data validation

* **Type checks**.

...y **FastAPI** usa las mismas declaraciones para:

* **Definir requerimientos**: desde request path parameters, query parameters, headers, bodies, dependencies, etc.
* **Convertir datos**: desde el request al tipo requerido.
* **Validar datos**: viniendo de cada request:
    * Generando **errores automáticos** devueltos al cliente cuando los datos son inválidos.
* **Documentar** la API usando OpenAPI:

Entonces, con esa declaración de tipos **FastAPI** te da <abbr title="convertir el string que viene de un HTTP request a datos de Python">"parsing"</abbr> automático del request.

///

## Validación de datos

	defer httpServer1.Close()
	httpServer2 := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		fmt.Fprintln(w, "fbe246edbd382902db9a4035df7dce8cb441357d minio.RELEASE.2016-10-07T01-16-39Z")
	}))
	defer httpServer2.Close()
	httpServer3 := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		http.Error(w, "", http.StatusNotFound)

			</h2>
			<div class="errormessage"><la:message key="labels.contact_site_admin" /></div>
		</div>
	</main>
	<jsp:include page="../footer.jsp" />
	<input type="hidden" id="contextPath" value="${pageContext.request.contextPath}" />
	<script type="text/javascript"
		src="${fe:url('/js/jquery-3.7.1.min.js')}"></script>
	<script type="text/javascript" src="${fe:url('/js/bootstrap.min.js')}"></script>

  fun addProxy(proxy: Proxy): FakeProxySelector {
    proxies.add(proxy)
    return this
  }

  override fun select(uri: URI): List<Proxy> {
    // Don't handle 'socket' schemes, which the RI's Socket class may request (for SOCKS).
    return if (uri.scheme == "http" || uri.scheme == "https") proxies else listOf(Proxy.NO_PROXY)
  }

  override fun connectFailed(
    uri: URI,
    sa: SocketAddress,
    ioe: IOException,
  ) {

        props.put("bb", "${aa}");
        DefaultModelBuildingRequest request = new DefaultModelBuildingRequest();

        Model model = Model.newBuilder().properties(props).build();

        SimpleProblemCollector collector = new SimpleProblemCollector();
        ModelInterpolator interpolator = createInterpolator();
        interpolator.interpolateModel(model, (Path) null, request, collector);

        assertCollectorState(0, 2, 0, collector);

}

// getObjectInArchiveFileHandler - GET Object in the archive file
func (api objectAPIHandlers) getObjectInArchiveFileHandler(ctx context.Context, objectAPI ObjectLayer, bucket, object string, w http.ResponseWriter, r *http.Request) {
	if crypto.S3.IsRequested(r.Header) || crypto.S3KMS.IsRequested(r.Header) { // If SSE-S3 or SSE-KMS present -> AWS fails with undefined error
		writeErrorResponse(ctx, w, errorCodes.ToAPIErr(ErrBadRequest), r.URL)
		return
	}

    ],
)
def get_client(request: pytest.FixtureRequest):
    clear_sqlmodel()
    # TODO: remove when updating SQL tutorial to use new lifespan API
    with warnings.catch_warnings(record=True):
        warnings.simplefilter("always")
        mod = importlib.import_module(f"docs_src.sql_databases.{request.param}")
        clear_sqlmodel()
        importlib.reload(mod)