/*
* 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 java.net.URI;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import org.apache.nifi.cluster.coordination.http.EndpointResponseMerger;
import org.apache.nifi.cluster.manager.NodeResponse;
import org.apache.nifi.web.api.dto.TemplateDTO;
import org.apache.nifi.web.api.entity.TemplateEntity;
import org.apache.nifi.web.api.entity.TemplatesEntity;
public class TemplatesEndpointMerger implements EndpointResponseMerger {
public static final Pattern TEMPLATES_URI_PATTERN = Pattern.compile("/nifi-api/process-groups/(?:(?:root)|(?:[a-f0-9\\-]{36}))/templates");
@Override
public boolean canHandle(final URI uri, final String method) {
return "GET".equalsIgnoreCase(method) && TEMPLATES_URI_PATTERN.matcher(uri.getPath()).matches();
}
protected Class<TemplatesEntity> getEntityClass() {
return TemplatesEntity.class;
}
protected Set<TemplateEntity> getDtos(final TemplatesEntity entity) {
return entity.getTemplates();
}
protected String getComponentId(final TemplateDTO dto) {
return dto.getId();
}
@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 TemplatesEntity responseEntity = clientResponse.getClientResponse().getEntity(getEntityClass());
// Find the templates that all nodes know about. We do this by mapping Template ID to Template and
// then for each node, removing any template whose ID is not known to that node. After iterating over
// all of the nodes, we are left with a Map whose contents are those Templates known by all nodes.
Map<String, TemplateEntity> templatesById = null;
for (final NodeResponse nodeResponse : successfulResponses) {
final TemplatesEntity entity = nodeResponse == clientResponse ? responseEntity : nodeResponse.getClientResponse().getEntity(TemplatesEntity.class);
final Set<TemplateEntity> templateEntities = entity.getTemplates();
final Map<String, TemplateEntity> nodeTemplatesById = templateEntities.stream().collect(Collectors.toMap(ent -> ent.getId(), ent -> ent));
if (templatesById == null) {
// Create new HashMap so that the map that we have is modifiable.
templatesById = new HashMap<>(nodeTemplatesById);
} else {
// Only keep templates that are known by this node.
templatesById.keySet().retainAll(nodeTemplatesById.keySet());
}
}
// Set the templates to the set of templates that all nodes know about
responseEntity.setTemplates(new HashSet<>(templatesById.values()));
// create a new client response
return new NodeResponse(clientResponse, responseEntity);
}
}