The `TestClient` is based on <a href="https://www.python-httpx.org" class="external-link" target="_blank">HTTPX</a>, and luckily, we can use it directly to test the API.

## Example { #example }

For a simple example, let's consider a file structure similar to the one described in [Bigger Applications](../tutorial/bigger-applications.md){.internal-link target=_blank} and [Testing](../tutorial/testing.md){.internal-link target=_blank}:

```
.
├── app

Al considerar estos conceptos, podrás **evaluar y diseñar** la mejor manera de implementar **tus propias APIs**.

En los próximos capítulos, te daré más **recetas concretas** para implementar aplicaciones de FastAPI.

   * specifier that is not already known to be valid.
   *
   * @throws ParseException if the specifier is not valid.
   */
  @CanIgnoreReturnValue // TODO(b/219820829): consider removing
  public static HostSpecifier from(String specifier) throws ParseException {
    try {
      return fromValid(specifier);
    } catch (IllegalArgumentException e) {

      }
    }

    // Test _all_ allowed characters (including surrogate values).
    for (char ch = 0x20; ch <= 0xFFFD; ch++) {
      // There are a small number of cases to consider, so just do it manually.
      if (ch == '&') {
        assertEscaping(xmlEscaper, "&amp;", ch);
      } else if (ch == '<') {
        assertEscaping(xmlEscaper, "&lt;", ch);
      } else if (ch == '>') {

Por exemplo, se você quiser ler ou manipular o corpo da requisição antes que ele seja processado pela sua aplicação.

/// danger | Perigo

Isso é um recurso "avançado".

Se você for um iniciante em **FastAPI** você deve considerar pular essa seção.

///

## Casos de Uso

Alguns casos de uso incluem:

  - type: dropdown
    id: author-go-experience
    attributes:
      label: "Go Programming Experience"
      description: "Would you consider yourself a novice, intermediate, or experienced Go programmer?"
      options:
        - "Novice"
        - "Intermediate"
        - "Experienced"
      default: 1

  - type: input

  public static @Nullable String emptyToNull(@Nullable String string) {
    return Platform.emptyToNull(string);
  }

  /**
   * Returns {@code true} if the given string is null or is the empty string.
   *
   * <p>Consider normalizing your string references with {@link #nullToEmpty}. If you do, you can
   * use {@link String#isEmpty()} instead of this method, and you won't need special null-safe forms

Y después de buscar durante mucho tiempo un framework similar y probar muchas alternativas diferentes, APIStar fue la mejor opción disponible.

Luego APIStar dejó de existir como servidor y Starlette fue creado, y fue una nueva y mejor base para tal sistema. Esa fue la inspiración final para construir **FastAPI**.

        assertEquals("", basePath);

        basePath = virtualHostHelper.getVirtualHostBasePath("  ", new HtmlNext("/test"));
        assertEquals("", basePath); // StringUtil.isBlank considers whitespace as blank
    }

    public void test_getVirtualHostKey() {
        ComponentUtil.setFessConfig(new FessConfig.SimpleImpl() {
            private static final long serialVersionUID = 1L;

 * ListenableFuture} directly.
 *
 * <p>For interoperability between {@code ListenableFuture} and <b>{@code CompletableFuture}</b>,
 * consider <a href="https://github.com/lukas-krecan/future-converter">Future Converter</a>.
 *
 * @author Sven Mawson
 * @since 10.0 (replacing {@code Futures.makeListenable}, which existed in 1.0)
 */
@J2ktIncompatible