How to use

getMinimalSupportedVersion

method

in

org.elasticsearch.common.io.stream.VersionedNamedWriteable

/**
 * Tests whether or not the custom should be serialized. The criteria are:
 * <ul>
 * <li>the output stream must be at least the minimum supported version of the custom</li>
 * <li>the output stream must have the feature required by the custom (if any) or not be a transport client</li>
 * </ul>
 * <p>
 * That is, we only serialize customs to clients than can understand the custom based on the version of the client and the features
 * that the client has. For transport clients we can be lenient in requiring a feature in which case we do not send the custom but
 * for connected nodes we always require that the node has the required feature.
 *
 * @param out    the output stream
 * @param custom the custom to serialize
 * @param <T>    the type of the custom
 * @return true if the custom should be serialized and false otherwise
 */
static <T extends VersionedNamedWriteable & FeatureAware> boolean shouldSerialize(final StreamOutput out, final T custom) {
  if (out.getVersion().before(custom.getMinimalSupportedVersion())) {
    return false;
  }
  if (custom.getRequiredFeature().isPresent()) {
    final String requiredFeature = custom.getRequiredFeature().get();
    // if it is a transport client we are lenient yet for a connected node it must have the required feature
    return out.hasFeature(requiredFeature) || out.hasFeature(TransportClient.TRANSPORT_CLIENT_FEATURE) == false;
  }
  return true;
}

/**
 * Tests whether or not the custom should be serialized. The criteria are:
 * <ul>
 * <li>the output stream must be at least the minimum supported version of the custom</li>
 * <li>the output stream must have the feature required by the custom (if any) or not be a transport client</li>
 * </ul>
 * <p>
 * That is, we only serialize customs to clients than can understand the custom based on the version of the client and the features
 * that the client has. For transport clients we can be lenient in requiring a feature in which case we do not send the custom but
 * for connected nodes we always require that the node has the required feature.
 *
 * @param out    the output stream
 * @param custom the custom to serialize
 * @param <T>    the type of the custom
 * @return true if the custom should be serialized and false otherwise
 */
static <T extends VersionedNamedWriteable & FeatureAware> boolean shouldSerialize(final StreamOutput out, final T custom) {
  if (out.getVersion().before(custom.getMinimalSupportedVersion())) {
    return false;
  }
  if (custom.getRequiredFeature().isPresent()) {
    final String requiredFeature = custom.getRequiredFeature().get();
    // if it is a transport client we are lenient yet for a connected node it must have the required feature
    return out.hasFeature(requiredFeature) || out.hasFeature(TransportClient.TRANSPORT_CLIENT_FEATURE) == false;
  }
  return true;
}

/**
 * Tests whether or not the custom should be serialized. The criteria are:
 * <ul>
 * <li>the output stream must be at least the minimum supported version of the custom</li>
 * <li>the output stream must have the feature required by the custom (if any) or not be a transport client</li>
 * </ul>
 * <p>
 * That is, we only serialize customs to clients than can understand the custom based on the version of the client and the features
 * that the client has. For transport clients we can be lenient in requiring a feature in which case we do not send the custom but
 * for connected nodes we always require that the node has the required feature.
 *
 * @param out    the output stream
 * @param custom the custom to serialize
 * @param <T>    the type of the custom
 * @return true if the custom should be serialized and false otherwise
 */
static <T extends VersionedNamedWriteable & FeatureAware> boolean shouldSerialize(final StreamOutput out, final T custom) {
  if (out.getVersion().before(custom.getMinimalSupportedVersion())) {
    return false;
  }
  if (custom.getRequiredFeature().isPresent()) {
    final String requiredFeature = custom.getRequiredFeature().get();
    // if it is a transport client we are lenient yet for a connected node it must have the required feature
    return out.hasFeature(requiredFeature) || out.hasFeature(TransportClient.TRANSPORT_CLIENT_FEATURE) == false;
  }
  return true;
}