/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.nifi.cluster.coordination.http.endpoints;
import org.apache.nifi.cluster.coordination.http.EndpointResponseMerger;
import org.apache.nifi.cluster.manager.NodeResponse;
import org.apache.nifi.cluster.protocol.NodeIdentifier;
import org.apache.nifi.web.api.entity.Entity;
import java.net.URI;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
public abstract class AbstractSingleDTOEndpoint<EntityType extends Entity, DtoType> implements EndpointResponseMerger {
@Override
public final NodeResponse merge(final URI uri, final String method, final Set<NodeResponse> successfulResponses, final Set<NodeResponse> problematicResponses, final NodeResponse clientResponse) {
if (!canHandle(uri, method)) {
throw new IllegalArgumentException("Cannot use Endpoint Mapper of type " + getClass().getSimpleName() + " to map responses for URI " + uri + ", HTTP Method " + method);
}
final EntityType responseEntity = clientResponse.getClientResponse().getEntity(getEntityClass());
final DtoType dto = getDto(responseEntity);
final Map<NodeIdentifier, DtoType> dtoMap = new HashMap<>();
for (final NodeResponse nodeResponse : successfulResponses) {
final EntityType nodeResponseEntity = nodeResponse == clientResponse ? responseEntity : nodeResponse.getClientResponse().getEntity(getEntityClass());
final DtoType nodeDto = getDto(nodeResponseEntity);
dtoMap.put(nodeResponse.getNodeId(), nodeDto);
}
mergeResponses(dto, dtoMap, successfulResponses, problematicResponses);
return new NodeResponse(clientResponse, responseEntity);
}
/**
* @return the class that represents the type of Entity that is expected by this response mapper
*/
protected abstract Class<EntityType> getEntityClass();
/**
* Extracts the DTO from the given entity
*
* @param entity the entity to extract the DTO from
* @return the DTO from the given entity
*/
protected abstract DtoType getDto(EntityType entity);
/**
* Merges the responses from all nodes in the given map into the single given DTO
*
* @param clientDto the DTO to merge responses into
* @param dtoMap the responses from all nodes
* @param successfulResponses the responses from nodes that completed the request successfully
* @param problematicResponses the responses from nodes that did not complete the request successfully
*/
protected abstract void mergeResponses(DtoType clientDto, Map<NodeIdentifier, DtoType> dtoMap, Set<NodeResponse> successfulResponses, Set<NodeResponse> problematicResponses);
}