### Función Personalizada para Generar ID Único

FastAPI usa un **ID único** para cada *path operation*, se usa para el **operation ID** y también para los nombres de cualquier modelo personalizado necesario, para requests o responses.

Puedes personalizar esa función. Toma un `APIRoute` y retorna un string.

For those cases, you can use a `Response` parameter.

## Use a `Response` parameter { #use-a-response-parameter }

You can declare a parameter of type `Response` in your *path operation function* (as you can do for cookies and headers).

And then you can set the `status_code` in that *temporal* response object.

{* ../../docs_src/response_change_status_code/tutorial001.py hl[1,9,12] *}

# Thus, the drive letter is replaced with the passed prefix.
# If no prefix is passed, by default, it's replaced with C:\, in case it's
# something else (ex. T:), which is a volume used in internal CI.
function replace_drive_letter_with_prefix () {
  local path_prefix
  if [[ -z "$2" ]]; then
    path_prefix="C:"
  else
    path_prefix="$2"
  fi
  sed -E "s|^[a-zA-Z]:|${path_prefix}|g" <<< "$1"

      Iterable<F> fromIterable, Function<? super F, ? extends T> function) {
    checkNotNull(fromIterable);
    checkNotNull(function);
    return new FluentIterable<T>() {
      @Override
      public Iterator<T> iterator() {
        return Iterators.transform(fromIterable.iterator(), function);
      }

      @Override

import com.google.common.annotations.J2ktIncompatible;
import com.google.errorprone.annotations.concurrent.LazyInit;
import com.google.j2objc.annotations.RetainedWith;
import java.util.function.BiConsumer;
import org.jspecify.annotations.Nullable;

/**
 * Implementation of {@link ImmutableMap} with exactly one entry.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 */
@GwtCompatible

## Example { #example }

Here's an example *path operation* with parameters using some of the above types.

{* ../../docs_src/extra_data_types/tutorial001_an_py310.py hl[1,3,12:16] *}

Note that the parameters inside the function have their natural data type, and you can, for example, perform normal date manipulations, like:

 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.timer;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.function.Supplier;

import org.apache.commons.io.output.ByteArrayOutputStream;
import org.apache.commons.text.StringEscapeUtils;
import org.codelibs.core.timer.TimeoutTarget;
import org.codelibs.fess.Constants;

For example, if you need to store it in a database.

For that, **FastAPI** provides a `jsonable_encoder()` function.

## Using the `jsonable_encoder` { #using-the-jsonable-encoder }

Let's imagine that you have a database `fake_db` that only receives JSON compatible data.

En algún momento habrías empezado la definición de la función, tenías los parámetros listos...

Pero luego tienes que llamar "ese método que convierte la primera letra a mayúscula".

¿Era `upper`? ¿Era `uppercase`? `first_uppercase`? `capitalize`?

Entonces, pruebas con el amigo del viejo programador, el autocompletado del editor.

//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

// Options for readDir function call
type readDirOpts struct {
	// The maximum number of entries to return
	count int
	// Follow directory symlink
	followDirSymlink bool
}

// Return all the entries at the directory dirPath.