{* ../../docs_src/stream_json_lines/tutorial001_py310.py ln[33:36] hl[34] *}

## Événements envoyés par le serveur (SSE) { #server-sent-events-sse }

* [`python-multipart`](https://github.com/Kludex/python-multipart) - Obligatoire si vous souhaitez prendre en charge l’<dfn title="convertir la chaîne issue d'une requête HTTP en données Python">« parsing »</dfn> de formulaires avec `request.form()`.

Utilisées par FastAPI :

 * #put}, {@link #invalidateAll(Iterable)} is implemented in terms of {@link #invalidate}. The
 * method {@link #cleanUp} is a no-op. All other methods throw an {@link
 * UnsupportedOperationException}.
 *
 * @author Charles Fry
 * @since 10.0
 */
@GwtCompatible
public abstract class AbstractCache<K, V> implements Cache<K, V> {

  /** Constructor for use by subclasses. */
  protected AbstractCache() {}

  /**
   * @since 11.0

	switch e.getFunctionName() {
	case sqlFnCoalesce:
		return coalesce(argVals)

	case sqlFnNullIf:
		return nullif(argVals[0], argVals[1])

	case sqlFnCharLength, sqlFnCharacterLength:
		return charlen(argVals[0])

	case sqlFnLower:
		return lowerCase(argVals[0])

	case sqlFnUpper:
		return upperCase(argVals[0])

	case sqlFnUTCNow:
		return handleUTCNow()

Nevertheless, we can declare the expected schema for the request body.

### Custom OpenAPI content type { #custom-openapi-content-type }

    You may not offer or impose any terms on any Covered Software in
    Source Code form that alters or restricts the applicable version of
    this License or the recipients' rights hereunder. You may choose to
    offer, and to charge a fee for, warranty, support, indemnity or
    liability obligations to one or more recipients of Covered Software.
    However, you may do so only on Your own behalf, and not on behalf of

 * #getUnchecked}.
 *
 * @param <K> the type of the cache's keys, which are not permitted to be null
 * @param <V> the type of the cache's values, which are not permitted to be null
 * @author Charles Fry
 * @since 11.0
 */
@GwtCompatible
public interface LoadingCache<K, V> extends Cache<K, V>, Function<K, V> {

  /**
   * Returns the value associated with {@code key} in this cache, first loading that value if

 * more simply:
 *
 * {@snippet :
 * CacheLoader<Key, Graph> loader = CacheLoader.from(key -> createExpensiveGraph(key));
 * }
 *
 * @author Charles Fry
 * @since 10.0
 */
@GwtCompatible
public abstract class CacheLoader<K, V> {
  /** Constructor for use by subclasses. */
  protected CacheLoader() {}

  /**

Dans ce cas, vous pouvez désactiver cette fonctionnalité dans **FastAPI**, avec le paramètre `separate_input_output_schemas=False`.

/// info | info

La prise en charge de `separate_input_output_schemas` a été ajoutée dans FastAPI `0.102.0`. 🤓

///

{* ../../docs_src/separate_openapi_schemas/tutorial002_py310.py hl[10] *}

Vous pouvez diffuser des données vers le client en utilisant les **Server-Sent Events** (SSE).

C'est similaire à [Diffuser des JSON Lines](stream-json-lines.md), mais cela utilise le format `text/event-stream`, pris en charge nativement par les navigateurs via l’API [`EventSource`](https://developer.mozilla.org/en-US/docs/Web/API/EventSource).

/// info | Info

Ajouté dans FastAPI 0.135.0.

///