Examples with ByteArrayCursorStreamProvider org.mule.runtime.core.internal.streaming.bytes.ByteArrayCursorStreamProvider used on opensource projects

Example 1 with ByteArrayCursorStreamProvider

use of org.mule.runtime.core.internal.streaming.bytes.ByteArrayCursorStreamProvider in project mule by mulesoft.

the class StreamingUtils method consumeRepeatablePayload.

/**
 * If the {@code event} has a repeatable payload (instance of {@link CursorProvider}), then this method returns a new
 * event which payload has an equivalent, already consumed structure. This functionality makes sense for cases like
 * caching in which the contents of the stream need to survive the completion of the event that generated it.
 * <p>
 * If the payload is a {@link CursorStreamProvider}, then it will be consumed into a {@link ByteArrayCursorStreamProvider}
 * so that the contents are fully in memory while still keeping repeatable byte streaming semantics.
 * <p>
 * If the payload is a {@link CursorIteratorProvider}, then the contents will be consumed into a {@link List}.
 * <p>
 * In any other case, the same input event is returned
 *
 * @param event an event which might have a repeatable payload
 * @return a {@link CoreEvent}
 * @since 4.1
 */
public static CoreEvent consumeRepeatablePayload(CoreEvent event) {
    TypedValue payload = event.getMessage().getPayload();
    final Object originalPayload = payload.getValue();
    if (originalPayload == null) {
        return event;
    }
    DataType originalDataType = payload.getDataType();
    TypedValue replacedPayload = null;
    if (originalPayload instanceof CursorStreamProvider) {
        Object consumedPayload = asCursorProvider(toByteArray((CursorStreamProvider) originalPayload));
        replacedPayload = new TypedValue(consumedPayload, DataType.builder(originalDataType).type(consumedPayload.getClass()).build());
    } else if (originalPayload instanceof CursorIteratorProvider) {
        List consumed = new LinkedList<>();
        ((CursorIteratorProvider) originalPayload).openCursor().forEachRemaining(consumed::add);
        DataType newDataType;
        if (originalDataType instanceof CollectionDataType) {
            final CollectionDataType collectionDataType = (CollectionDataType) originalDataType;
            newDataType = DataType.builder(originalDataType).collectionType(consumed.getClass()).itemType(collectionDataType.getItemDataType().getType()).itemMediaType(collectionDataType.getItemDataType().getMediaType()).build();
        } else {
            newDataType = DataType.builder(originalDataType).type(consumed.getClass()).build();
        }
        replacedPayload = new TypedValue(consumed, newDataType);
    }
    if (replacedPayload != null) {
        event = CoreEvent.builder(event).message(Message.builder(event.getMessage()).payload(replacedPayload).build()).build();
    }
    return event;
}