hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-router/src/main/java/org/apache/hadoop/yarn/server/router/webapp/RouterWebServiceUtil.java - hadoop - Git at Google

 /**
  * 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.hadoop.yarn.server.router.webapp;

 import static javax.servlet.http.HttpServletResponse.SC_NO_CONTENT;
 import static javax.servlet.http.HttpServletResponse.SC_OK;

 import java.io.IOException;
 import java.security.PrivilegedExceptionAction;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;

 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.core.HttpHeaders;
 import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.MultivaluedMap;
 import javax.ws.rs.core.Response;
 import javax.ws.rs.core.Response.ResponseBuilder;

 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.yarn.api.records.YarnApplicationState;
 import org.apache.hadoop.yarn.server.resourcemanager.webapp.RMWebAppUtil;
 import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.AppInfo;
 import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.AppsInfo;
 import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.ClusterMetricsInfo;
 import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.NodeInfo;
 import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.NodesInfo;
 import org.apache.hadoop.yarn.server.uam.UnmanagedApplicationManager;
 import org.apache.hadoop.yarn.webapp.BadRequestException;
 import org.apache.hadoop.yarn.webapp.ForbiddenException;
 import org.apache.hadoop.yarn.webapp.NotFoundException;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

 import com.sun.jersey.api.ConflictException;
 import com.sun.jersey.api.client.Client;
 import com.sun.jersey.api.client.ClientResponse;
 import com.sun.jersey.api.client.WebResource;
 import com.sun.jersey.api.client.WebResource.Builder;
 import com.sun.jersey.core.util.MultivaluedMapImpl;

 /**
  * The Router webservice util class.
  */
 public final class RouterWebServiceUtil {

   private static String user = "YarnRouter";

   private static final Logger LOG =
       LoggerFactory.getLogger(RouterWebServiceUtil.class.getName());

   private final static String PARTIAL_REPORT = "Partial Report ";

   /** Disable constructor. */
   private RouterWebServiceUtil() {
   }

   /**
    * Creates and performs a REST call to a specific WebService.
    *
    * @param webApp the address of the remote webap
    * @param hsr the servlet request
    * @param returnType the return type of the REST call
    * @param <T> Type of return object.
    * @param method the HTTP method of the REST call
    * @param targetPath additional path to add to the webapp address
    * @param formParam the form parameters as input for a specific REST call
    * @param additionalParam the query parameters as input for a specific REST
    *          call in case the call has no servlet request
    * @return the retrieved entity from the REST call
    */
   protected static <T> T genericForward(
       final String webApp, final HttpServletRequest hsr,
       final Class<T> returnType, final HTTPMethods method,
       final String targetPath, final Object formParam,
       final Map<String, String[]> additionalParam) {

     UserGroupInformation callerUGI = null;

     if (hsr != null) {
       callerUGI = RMWebAppUtil.getCallerUserGroupInformation(hsr, true);
     } else {
       // user not required
       callerUGI = UserGroupInformation.createRemoteUser(user);

     }

     if (callerUGI == null) {
       LOG.error("Unable to obtain user name, user not authenticated");
       return null;
     }

     try {
       return callerUGI.doAs(new PrivilegedExceptionAction<T>() {
         @SuppressWarnings("unchecked")
         @Override
         public T run() {

           Map<String, String[]> paramMap = null;

           // We can have hsr or additionalParam. There are no case with both.
           if (hsr != null) {
             paramMap = hsr.getParameterMap();
           } else if (additionalParam != null) {
             paramMap = additionalParam;
           }

           ClientResponse response = RouterWebServiceUtil.invokeRMWebService(
               webApp, targetPath, method,
               (hsr == null) ? null : hsr.getPathInfo(), paramMap, formParam,
               getMediaTypeFromHttpServletRequest(hsr, returnType));
           if (Response.class.equals(returnType)) {
             return (T) RouterWebServiceUtil.clientResponseToResponse(response);
           }
           // YARN RM can answer with Status.OK or it throws an exception
           if (response.getStatus() == SC_OK) {
             return response.getEntity(returnType);
           }
           if (response.getStatus() == SC_NO_CONTENT) {
             try {
               return returnType.getConstructor().newInstance();
             } catch (RuntimeException | ReflectiveOperationException e) {
               LOG.error("Cannot create empty entity for {}", returnType, e);
             }
           }
           RouterWebServiceUtil.retrieveException(response);
           return null;
         }
       });
     } catch (InterruptedException e) {
       return null;
     } catch (IOException e) {
       return null;
     }
   }

   /**
    * Performs an invocation of a REST call on a remote RMWebService.
    *
    * @param additionalParam
    */
   private static ClientResponse invokeRMWebService(String webApp, String path,
       HTTPMethods method, String additionalPath,
       Map<String, String[]> queryParams, Object formParam, String mediaType) {
     Client client = Client.create();

     WebResource webResource = client.resource(webApp).path(path);

     if (additionalPath != null && !additionalPath.isEmpty()) {
       webResource = webResource.path(additionalPath);
     }

     if (queryParams != null && !queryParams.isEmpty()) {
       MultivaluedMap<String, String> paramMap = new MultivaluedMapImpl();

       for (Entry<String, String[]> param : queryParams.entrySet()) {
         String[] values = param.getValue();
         for (int i = 0; i < values.length; i++) {
           paramMap.add(param.getKey(), values[i]);
         }
       }
       webResource = webResource.queryParams(paramMap);
     }

     Builder builder = null;
     if (formParam != null) {
       builder = webResource.entity(formParam, mediaType);
       builder = builder.accept(mediaType);
     } else {
       builder = webResource.accept(mediaType);
     }

     ClientResponse response = null;

     switch (method) {
     case DELETE:
       response = builder.delete(ClientResponse.class);
       break;
     case GET:
       response = builder.get(ClientResponse.class);
       break;
     case POST:
       response = builder.post(ClientResponse.class);
       break;
     case PUT:
       response = builder.put(ClientResponse.class);
       break;
     default:
       break;
     }

     return response;
   }

   public static Response clientResponseToResponse(ClientResponse r) {
     if (r == null) {
       return null;
     }
     // copy the status code
     ResponseBuilder rb = Response.status(r.getStatus());
     // copy all the headers
     for (Entry<String, List<String>> entry : r.getHeaders().entrySet()) {
       for (String value : entry.getValue()) {
         rb.header(entry.getKey(), value);
       }
     }
     // copy the entity
     rb.entity(r.getEntityInputStream());
     // return the response
     return rb.build();
   }

   public static void retrieveException(ClientResponse response) {
     String serverErrorMsg = response.getEntity(String.class);
     int status = response.getStatus();
     if (status == 400) {
       throw new BadRequestException(serverErrorMsg);
     }
     if (status == 403) {
       throw new ForbiddenException(serverErrorMsg);
     }
     if (status == 404) {
       throw new NotFoundException(serverErrorMsg);
     }
     if (status == 409) {
       throw new ConflictException(serverErrorMsg);
     }

   }

   /**
    * Merges a list of AppInfo grouping by ApplicationId. Our current policy is
    * to merge the application reports from the reacheable SubClusters. Via
    * configuration parameter, we decide whether to return applications for which
    * the primary AM is missing or to omit them.
    *
    * @param appsInfo a list of AppInfo to merge
    * @param returnPartialResult if the merge AppsInfo should contain partial
    *          result or not
    * @return the merged AppsInfo
    */
   public static AppsInfo mergeAppsInfo(ArrayList<AppInfo> appsInfo,
       boolean returnPartialResult) {
     AppsInfo allApps = new AppsInfo();

     Map<String, AppInfo> federationAM = new HashMap<String, AppInfo>();
     Map<String, AppInfo> federationUAMSum = new HashMap<String, AppInfo>();
     for (AppInfo a : appsInfo) {
       // Check if this AppInfo is an AM
       if (a.getAMHostHttpAddress() != null) {
         // Insert in the list of AM
         federationAM.put(a.getAppId(), a);
         // Check if there are any UAM found before
         if (federationUAMSum.containsKey(a.getAppId())) {
           // Merge the current AM with the found UAM
           mergeAMWithUAM(a, federationUAMSum.get(a.getAppId()));
           // Remove the sum of the UAMs
           federationUAMSum.remove(a.getAppId());
         }
         // This AppInfo is an UAM
       } else {
         if (federationAM.containsKey(a.getAppId())) {
           // Merge the current UAM with its own AM
           mergeAMWithUAM(federationAM.get(a.getAppId()), a);
         } else if (federationUAMSum.containsKey(a.getAppId())) {
           // Merge the current UAM with its own UAM and update the list of UAM
           federationUAMSum.put(a.getAppId(),
               mergeUAMWithUAM(federationUAMSum.get(a.getAppId()), a));
         } else {
           // Insert in the list of UAM
           federationUAMSum.put(a.getAppId(), a);
         }
       }
     }

     // Check the remaining UAMs are depending or not from federation
     for (AppInfo a : federationUAMSum.values()) {
       if (returnPartialResult || (a.getName() != null
           && !(a.getName().startsWith(UnmanagedApplicationManager.APP_NAME)
               || a.getName().startsWith(PARTIAL_REPORT)))) {
         federationAM.put(a.getAppId(), a);
       }
     }

     allApps.addAll(new ArrayList<AppInfo>(federationAM.values()));
     return allApps;
   }

   private static AppInfo mergeUAMWithUAM(AppInfo uam1, AppInfo uam2) {
     AppInfo partialReport = new AppInfo();
     partialReport.setAppId(uam1.getAppId());
     partialReport.setName(PARTIAL_REPORT + uam1.getAppId());
     // We pick the status of the first uam
     partialReport.setState(uam1.getState());
     // Merge the newly partial AM with UAM1 and then with UAM2
     mergeAMWithUAM(partialReport, uam1);
     mergeAMWithUAM(partialReport, uam2);
     return partialReport;
   }

   private static void mergeAMWithUAM(AppInfo am, AppInfo uam) {
     am.setPreemptedResourceMB(
         am.getPreemptedResourceMB() + uam.getPreemptedResourceMB());
     am.setPreemptedResourceVCores(
         am.getPreemptedResourceVCores() + uam.getPreemptedResourceVCores());
     am.setNumNonAMContainerPreempted(am.getNumNonAMContainerPreempted()
         + uam.getNumNonAMContainerPreempted());
     am.setNumAMContainerPreempted(
         am.getNumAMContainerPreempted() + uam.getNumAMContainerPreempted());
     am.setPreemptedMemorySeconds(
         am.getPreemptedMemorySeconds() + uam.getPreemptedMemorySeconds());
     am.setPreemptedVcoreSeconds(
         am.getPreemptedVcoreSeconds() + uam.getPreemptedVcoreSeconds());

     if (am.getState() == YarnApplicationState.RUNNING
         && uam.getState() == am.getState()) {

       am.getResourceRequests().addAll(uam.getResourceRequests());

       am.setAllocatedMB(am.getAllocatedMB() + uam.getAllocatedMB());
       am.setAllocatedVCores(am.getAllocatedVCores() + uam.getAllocatedVCores());
       am.setReservedMB(am.getReservedMB() + uam.getReservedMB());
       am.setReservedVCores(am.getReservedVCores() + uam.getReservedMB());
       am.setRunningContainers(
           am.getRunningContainers() + uam.getRunningContainers());
       am.setMemorySeconds(am.getMemorySeconds() + uam.getMemorySeconds());
       am.setVcoreSeconds(am.getVcoreSeconds() + uam.getVcoreSeconds());
     }
   }

   /**
    * Deletes all the duplicate NodeInfo by discarding the old instances.
    *
    * @param nodes a list of NodeInfo to check for duplicates
    * @return a NodesInfo that contains a list of NodeInfos without duplicates
    */
   public static NodesInfo deleteDuplicateNodesInfo(ArrayList<NodeInfo> nodes) {
     NodesInfo nodesInfo = new NodesInfo();

     Map<String, NodeInfo> nodesMap = new LinkedHashMap<>();
     for (NodeInfo node : nodes) {
       String nodeId = node.getNodeId();
       // If the node already exists, it could be an old instance
       if (nodesMap.containsKey(nodeId)) {
         // Check if the node is an old instance
         if (nodesMap.get(nodeId).getLastHealthUpdate() < node
             .getLastHealthUpdate()) {
           nodesMap.put(node.getNodeId(), node);
         }
       } else {
         nodesMap.put(node.getNodeId(), node);
       }
     }
     nodesInfo.addAll(new ArrayList<NodeInfo>(nodesMap.values()));
     return nodesInfo;
   }

   /**
    * Adds all the values from the second ClusterMetricsInfo to the first one.
    *
    * @param metrics the ClusterMetricsInfo we want to update
    * @param metricsResponse the ClusterMetricsInfo we want to add to the first
    *          param
    */
   public static void mergeMetrics(ClusterMetricsInfo metrics,
       ClusterMetricsInfo metricsResponse) {
     metrics.setAppsSubmitted(
         metrics.getAppsSubmitted() + metricsResponse.getAppsSubmitted());
     metrics.setAppsCompleted(
         metrics.getAppsCompleted() + metricsResponse.getAppsCompleted());
     metrics.setAppsPending(
         metrics.getAppsPending() + metricsResponse.getAppsPending());
     metrics.setAppsRunning(
         metrics.getAppsRunning() + metricsResponse.getAppsRunning());
     metrics.setAppsFailed(
         metrics.getAppsFailed() + metricsResponse.getAppsFailed());
     metrics.setAppsKilled(
         metrics.getAppsKilled() + metricsResponse.getAppsKilled());

     metrics.setReservedMB(
         metrics.getReservedMB() + metricsResponse.getReservedMB());
     metrics.setAvailableMB(
         metrics.getAvailableMB() + metricsResponse.getAvailableMB());
     metrics.setAllocatedMB(
         metrics.getAllocatedMB() + metricsResponse.getAllocatedMB());

     metrics.setReservedVirtualCores(metrics.getReservedVirtualCores()
         + metricsResponse.getReservedVirtualCores());
     metrics.setAvailableVirtualCores(metrics.getAvailableVirtualCores()
         + metricsResponse.getAvailableVirtualCores());
     metrics.setAllocatedVirtualCores(metrics.getAllocatedVirtualCores()
         + metricsResponse.getAllocatedVirtualCores());

     metrics.setContainersAllocated(metrics.getContainersAllocated()
         + metricsResponse.getContainersAllocated());
     metrics.setContainersReserved(metrics.getReservedContainers()
         + metricsResponse.getReservedContainers());
     metrics.setContainersPending(metrics.getPendingContainers()
         + metricsResponse.getPendingContainers());

     metrics.setTotalMB(metrics.getTotalMB()
         + metricsResponse.getTotalMB());
     metrics.setTotalVirtualCores(metrics.getTotalVirtualCores()
         + metricsResponse.getTotalVirtualCores());
     metrics.setTotalNodes(metrics.getTotalNodes()
         + metricsResponse.getTotalNodes());
     metrics.setLostNodes(metrics.getLostNodes()
         + metricsResponse.getLostNodes());
     metrics.setUnhealthyNodes(metrics.getUnhealthyNodes()
         + metricsResponse.getUnhealthyNodes());
     metrics.setDecommissioningNodes(metrics.getDecommissioningNodes()
         + metricsResponse.getDecommissioningNodes());
     metrics.setDecommissionedNodes(metrics.getDecommissionedNodes()
         + metricsResponse.getDecommissionedNodes());
     metrics.setRebootedNodes(metrics.getRebootedNodes()
         + metricsResponse.getRebootedNodes());
     metrics.setActiveNodes(metrics.getActiveNodes()
         + metricsResponse.getActiveNodes());
     metrics.setShutdownNodes(metrics.getShutdownNodes()
         + metricsResponse.getShutdownNodes());
   }

   /**
    * Extract from HttpServletRequest the MediaType in output.
    */
   protected static <T> String getMediaTypeFromHttpServletRequest(
       HttpServletRequest request, final Class<T> returnType) {
     if (request == null) {
       // By default we return XML for REST call without HttpServletRequest
       return MediaType.APPLICATION_XML;
     }
     // TODO
     if (!returnType.equals(Response.class)) {
       return MediaType.APPLICATION_XML;
     }
     String header = request.getHeader(HttpHeaders.ACCEPT);
     if (header == null || header.equals("*")) {
       // By default we return JSON
       return MediaType.APPLICATION_JSON;
     }
     return header;
   }

 }
	/**
	* 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.hadoop.yarn.server.router.webapp;

	import static javax.servlet.http.HttpServletResponse.SC_NO_CONTENT;
	import static javax.servlet.http.HttpServletResponse.SC_OK;

	import java.io.IOException;
	import java.security.PrivilegedExceptionAction;
	import java.util.ArrayList;
	import java.util.HashMap;
	import java.util.LinkedHashMap;
	import java.util.List;
	import java.util.Map;
	import java.util.Map.Entry;

	import javax.servlet.http.HttpServletRequest;
	import javax.ws.rs.core.HttpHeaders;
	import javax.ws.rs.core.MediaType;
	import javax.ws.rs.core.MultivaluedMap;
	import javax.ws.rs.core.Response;
	import javax.ws.rs.core.Response.ResponseBuilder;

	import org.apache.hadoop.security.UserGroupInformation;
	import org.apache.hadoop.yarn.api.records.YarnApplicationState;
	import org.apache.hadoop.yarn.server.resourcemanager.webapp.RMWebAppUtil;
	import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.AppInfo;
	import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.AppsInfo;
	import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.ClusterMetricsInfo;
	import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.NodeInfo;
	import org.apache.hadoop.yarn.server.resourcemanager.webapp.dao.NodesInfo;
	import org.apache.hadoop.yarn.server.uam.UnmanagedApplicationManager;
	import org.apache.hadoop.yarn.webapp.BadRequestException;
	import org.apache.hadoop.yarn.webapp.ForbiddenException;
	import org.apache.hadoop.yarn.webapp.NotFoundException;
	import org.slf4j.Logger;
	import org.slf4j.LoggerFactory;

	import com.sun.jersey.api.ConflictException;
	import com.sun.jersey.api.client.Client;
	import com.sun.jersey.api.client.ClientResponse;
	import com.sun.jersey.api.client.WebResource;
	import com.sun.jersey.api.client.WebResource.Builder;
	import com.sun.jersey.core.util.MultivaluedMapImpl;

	/**
	* The Router webservice util class.
	*/
	public final class RouterWebServiceUtil {

	private static String user = "YarnRouter";

	private static final Logger LOG =
	LoggerFactory.getLogger(RouterWebServiceUtil.class.getName());

	private final static String PARTIAL_REPORT = "Partial Report ";

	/** Disable constructor. */
	private RouterWebServiceUtil() {
	}

	/**
	* Creates and performs a REST call to a specific WebService.
	*
	* @param webApp the address of the remote webap
	* @param hsr the servlet request
	* @param returnType the return type of the REST call
	* @param <T> Type of return object.
	* @param method the HTTP method of the REST call
	* @param targetPath additional path to add to the webapp address
	* @param formParam the form parameters as input for a specific REST call
	* @param additionalParam the query parameters as input for a specific REST
	* call in case the call has no servlet request
	* @return the retrieved entity from the REST call
	*/
	protected static <T> T genericForward(
	final String webApp, final HttpServletRequest hsr,
	final Class<T> returnType, final HTTPMethods method,
	final String targetPath, final Object formParam,
	final Map<String, String[]> additionalParam) {

	UserGroupInformation callerUGI = null;

	if (hsr != null) {
	callerUGI = RMWebAppUtil.getCallerUserGroupInformation(hsr, true);
	} else {
	// user not required
	callerUGI = UserGroupInformation.createRemoteUser(user);

	}

	if (callerUGI == null) {
	LOG.error("Unable to obtain user name, user not authenticated");
	return null;
	}

	try {
	return callerUGI.doAs(new PrivilegedExceptionAction<T>() {
	@SuppressWarnings("unchecked")
	@Override
	public T run() {

	Map<String, String[]> paramMap = null;

	// We can have hsr or additionalParam. There are no case with both.
	if (hsr != null) {
	paramMap = hsr.getParameterMap();
	} else if (additionalParam != null) {
	paramMap = additionalParam;
	}

	ClientResponse response = RouterWebServiceUtil.invokeRMWebService(
	webApp, targetPath, method,
	(hsr == null) ? null : hsr.getPathInfo(), paramMap, formParam,
	getMediaTypeFromHttpServletRequest(hsr, returnType));
	if (Response.class.equals(returnType)) {
	return (T) RouterWebServiceUtil.clientResponseToResponse(response);
	}
	// YARN RM can answer with Status.OK or it throws an exception
	if (response.getStatus() == SC_OK) {
	return response.getEntity(returnType);
	}
	if (response.getStatus() == SC_NO_CONTENT) {
	try {
	return returnType.getConstructor().newInstance();
	} catch (RuntimeException \| ReflectiveOperationException e) {
	LOG.error("Cannot create empty entity for {}", returnType, e);
	}
	}
	RouterWebServiceUtil.retrieveException(response);
	return null;
	}
	});
	} catch (InterruptedException e) {
	return null;
	} catch (IOException e) {
	return null;
	}
	}

	/**
	* Performs an invocation of a REST call on a remote RMWebService.
	*
	* @param additionalParam
	*/
	private static ClientResponse invokeRMWebService(String webApp, String path,
	HTTPMethods method, String additionalPath,
	Map<String, String[]> queryParams, Object formParam, String mediaType) {
	Client client = Client.create();

	WebResource webResource = client.resource(webApp).path(path);

	if (additionalPath != null && !additionalPath.isEmpty()) {
	webResource = webResource.path(additionalPath);
	}

	if (queryParams != null && !queryParams.isEmpty()) {
	MultivaluedMap<String, String> paramMap = new MultivaluedMapImpl();

	for (Entry<String, String[]> param : queryParams.entrySet()) {
	String[] values = param.getValue();
	for (int i = 0; i < values.length; i++) {
	paramMap.add(param.getKey(), values[i]);
	}
	}
	webResource = webResource.queryParams(paramMap);
	}

	Builder builder = null;
	if (formParam != null) {
	builder = webResource.entity(formParam, mediaType);
	builder = builder.accept(mediaType);
	} else {
	builder = webResource.accept(mediaType);
	}

	ClientResponse response = null;

	switch (method) {
	case DELETE:
	response = builder.delete(ClientResponse.class);
	break;
	case GET:
	response = builder.get(ClientResponse.class);
	break;
	case POST:
	response = builder.post(ClientResponse.class);
	break;
	case PUT:
	response = builder.put(ClientResponse.class);
	break;
	default:
	break;
	}

	return response;
	}

	public static Response clientResponseToResponse(ClientResponse r) {
	if (r == null) {
	return null;
	}
	// copy the status code
	ResponseBuilder rb = Response.status(r.getStatus());
	// copy all the headers
	for (Entry<String, List<String>> entry : r.getHeaders().entrySet()) {
	for (String value : entry.getValue()) {
	rb.header(entry.getKey(), value);
	}
	}
	// copy the entity
	rb.entity(r.getEntityInputStream());
	// return the response
	return rb.build();
	}

	public static void retrieveException(ClientResponse response) {
	String serverErrorMsg = response.getEntity(String.class);
	int status = response.getStatus();
	if (status == 400) {
	throw new BadRequestException(serverErrorMsg);
	}
	if (status == 403) {
	throw new ForbiddenException(serverErrorMsg);
	}
	if (status == 404) {
	throw new NotFoundException(serverErrorMsg);
	}
	if (status == 409) {
	throw new ConflictException(serverErrorMsg);
	}

	}

	/**
	* Merges a list of AppInfo grouping by ApplicationId. Our current policy is
	* to merge the application reports from the reacheable SubClusters. Via
	* configuration parameter, we decide whether to return applications for which
	* the primary AM is missing or to omit them.
	*
	* @param appsInfo a list of AppInfo to merge
	* @param returnPartialResult if the merge AppsInfo should contain partial
	* result or not
	* @return the merged AppsInfo
	*/
	public static AppsInfo mergeAppsInfo(ArrayList<AppInfo> appsInfo,
	boolean returnPartialResult) {
	AppsInfo allApps = new AppsInfo();

	Map<String, AppInfo> federationAM = new HashMap<String, AppInfo>();
	Map<String, AppInfo> federationUAMSum = new HashMap<String, AppInfo>();
	for (AppInfo a : appsInfo) {
	// Check if this AppInfo is an AM
	if (a.getAMHostHttpAddress() != null) {
	// Insert in the list of AM
	federationAM.put(a.getAppId(), a);
	// Check if there are any UAM found before
	if (federationUAMSum.containsKey(a.getAppId())) {
	// Merge the current AM with the found UAM
	mergeAMWithUAM(a, federationUAMSum.get(a.getAppId()));
	// Remove the sum of the UAMs
	federationUAMSum.remove(a.getAppId());
	}
	// This AppInfo is an UAM
	} else {
	if (federationAM.containsKey(a.getAppId())) {
	// Merge the current UAM with its own AM
	mergeAMWithUAM(federationAM.get(a.getAppId()), a);
	} else if (federationUAMSum.containsKey(a.getAppId())) {
	// Merge the current UAM with its own UAM and update the list of UAM
	federationUAMSum.put(a.getAppId(),
	mergeUAMWithUAM(federationUAMSum.get(a.getAppId()), a));
	} else {
	// Insert in the list of UAM
	federationUAMSum.put(a.getAppId(), a);
	}
	}
	}

	// Check the remaining UAMs are depending or not from federation
	for (AppInfo a : federationUAMSum.values()) {
	if (returnPartialResult \|\| (a.getName() != null
	&& !(a.getName().startsWith(UnmanagedApplicationManager.APP_NAME)
	\|\| a.getName().startsWith(PARTIAL_REPORT)))) {
	federationAM.put(a.getAppId(), a);
	}
	}

	allApps.addAll(new ArrayList<AppInfo>(federationAM.values()));
	return allApps;
	}

	private static AppInfo mergeUAMWithUAM(AppInfo uam1, AppInfo uam2) {
	AppInfo partialReport = new AppInfo();
	partialReport.setAppId(uam1.getAppId());
	partialReport.setName(PARTIAL_REPORT + uam1.getAppId());
	// We pick the status of the first uam
	partialReport.setState(uam1.getState());
	// Merge the newly partial AM with UAM1 and then with UAM2
	mergeAMWithUAM(partialReport, uam1);
	mergeAMWithUAM(partialReport, uam2);
	return partialReport;
	}

	private static void mergeAMWithUAM(AppInfo am, AppInfo uam) {
	am.setPreemptedResourceMB(
	am.getPreemptedResourceMB() + uam.getPreemptedResourceMB());
	am.setPreemptedResourceVCores(
	am.getPreemptedResourceVCores() + uam.getPreemptedResourceVCores());
	am.setNumNonAMContainerPreempted(am.getNumNonAMContainerPreempted()
	+ uam.getNumNonAMContainerPreempted());
	am.setNumAMContainerPreempted(
	am.getNumAMContainerPreempted() + uam.getNumAMContainerPreempted());
	am.setPreemptedMemorySeconds(
	am.getPreemptedMemorySeconds() + uam.getPreemptedMemorySeconds());
	am.setPreemptedVcoreSeconds(
	am.getPreemptedVcoreSeconds() + uam.getPreemptedVcoreSeconds());

	if (am.getState() == YarnApplicationState.RUNNING
	&& uam.getState() == am.getState()) {

	am.getResourceRequests().addAll(uam.getResourceRequests());

	am.setAllocatedMB(am.getAllocatedMB() + uam.getAllocatedMB());
	am.setAllocatedVCores(am.getAllocatedVCores() + uam.getAllocatedVCores());
	am.setReservedMB(am.getReservedMB() + uam.getReservedMB());
	am.setReservedVCores(am.getReservedVCores() + uam.getReservedMB());
	am.setRunningContainers(
	am.getRunningContainers() + uam.getRunningContainers());
	am.setMemorySeconds(am.getMemorySeconds() + uam.getMemorySeconds());
	am.setVcoreSeconds(am.getVcoreSeconds() + uam.getVcoreSeconds());
	}
	}

	/**
	* Deletes all the duplicate NodeInfo by discarding the old instances.
	*
	* @param nodes a list of NodeInfo to check for duplicates
	* @return a NodesInfo that contains a list of NodeInfos without duplicates
	*/
	public static NodesInfo deleteDuplicateNodesInfo(ArrayList<NodeInfo> nodes) {
	NodesInfo nodesInfo = new NodesInfo();

	Map<String, NodeInfo> nodesMap = new LinkedHashMap<>();
	for (NodeInfo node : nodes) {
	String nodeId = node.getNodeId();
	// If the node already exists, it could be an old instance
	if (nodesMap.containsKey(nodeId)) {
	// Check if the node is an old instance
	if (nodesMap.get(nodeId).getLastHealthUpdate() < node
	.getLastHealthUpdate()) {
	nodesMap.put(node.getNodeId(), node);
	}
	} else {
	nodesMap.put(node.getNodeId(), node);
	}
	}
	nodesInfo.addAll(new ArrayList<NodeInfo>(nodesMap.values()));
	return nodesInfo;
	}

	/**
	* Adds all the values from the second ClusterMetricsInfo to the first one.
	*
	* @param metrics the ClusterMetricsInfo we want to update
	* @param metricsResponse the ClusterMetricsInfo we want to add to the first
	* param
	*/
	public static void mergeMetrics(ClusterMetricsInfo metrics,
	ClusterMetricsInfo metricsResponse) {
	metrics.setAppsSubmitted(
	metrics.getAppsSubmitted() + metricsResponse.getAppsSubmitted());
	metrics.setAppsCompleted(
	metrics.getAppsCompleted() + metricsResponse.getAppsCompleted());
	metrics.setAppsPending(
	metrics.getAppsPending() + metricsResponse.getAppsPending());
	metrics.setAppsRunning(
	metrics.getAppsRunning() + metricsResponse.getAppsRunning());
	metrics.setAppsFailed(
	metrics.getAppsFailed() + metricsResponse.getAppsFailed());
	metrics.setAppsKilled(
	metrics.getAppsKilled() + metricsResponse.getAppsKilled());

	metrics.setReservedMB(
	metrics.getReservedMB() + metricsResponse.getReservedMB());
	metrics.setAvailableMB(
	metrics.getAvailableMB() + metricsResponse.getAvailableMB());
	metrics.setAllocatedMB(
	metrics.getAllocatedMB() + metricsResponse.getAllocatedMB());

	metrics.setReservedVirtualCores(metrics.getReservedVirtualCores()
	+ metricsResponse.getReservedVirtualCores());
	metrics.setAvailableVirtualCores(metrics.getAvailableVirtualCores()
	+ metricsResponse.getAvailableVirtualCores());
	metrics.setAllocatedVirtualCores(metrics.getAllocatedVirtualCores()
	+ metricsResponse.getAllocatedVirtualCores());

	metrics.setContainersAllocated(metrics.getContainersAllocated()
	+ metricsResponse.getContainersAllocated());
	metrics.setContainersReserved(metrics.getReservedContainers()
	+ metricsResponse.getReservedContainers());
	metrics.setContainersPending(metrics.getPendingContainers()
	+ metricsResponse.getPendingContainers());

	metrics.setTotalMB(metrics.getTotalMB()
	+ metricsResponse.getTotalMB());
	metrics.setTotalVirtualCores(metrics.getTotalVirtualCores()
	+ metricsResponse.getTotalVirtualCores());
	metrics.setTotalNodes(metrics.getTotalNodes()
	+ metricsResponse.getTotalNodes());
	metrics.setLostNodes(metrics.getLostNodes()
	+ metricsResponse.getLostNodes());
	metrics.setUnhealthyNodes(metrics.getUnhealthyNodes()
	+ metricsResponse.getUnhealthyNodes());
	metrics.setDecommissioningNodes(metrics.getDecommissioningNodes()
	+ metricsResponse.getDecommissioningNodes());
	metrics.setDecommissionedNodes(metrics.getDecommissionedNodes()
	+ metricsResponse.getDecommissionedNodes());
	metrics.setRebootedNodes(metrics.getRebootedNodes()
	+ metricsResponse.getRebootedNodes());
	metrics.setActiveNodes(metrics.getActiveNodes()
	+ metricsResponse.getActiveNodes());
	metrics.setShutdownNodes(metrics.getShutdownNodes()
	+ metricsResponse.getShutdownNodes());
	}

	/**
	* Extract from HttpServletRequest the MediaType in output.
	*/
	protected static <T> String getMediaTypeFromHttpServletRequest(
	HttpServletRequest request, final Class<T> returnType) {
	if (request == null) {
	// By default we return XML for REST call without HttpServletRequest
	return MediaType.APPLICATION_XML;
	}
	// TODO
	if (!returnType.equals(Response.class)) {
	return MediaType.APPLICATION_XML;
	}
	String header = request.getHeader(HttpHeaders.ACCEPT);
	if (header == null \|\| header.equals("*")) {
	// By default we return JSON
	return MediaType.APPLICATION_JSON;
	}
	return header;
	}

	}