/**
* 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.hdfs.server.namenode;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.MD5MD5CRC32FileChecksum;
import org.apache.hadoop.hdfs.DFSClient;
import org.apache.hadoop.hdfs.DFSConfigKeys;
import org.apache.hadoop.hdfs.HdfsConfiguration;
import org.apache.hadoop.hdfs.protocol.DatanodeID;
import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
import org.apache.hadoop.hdfs.server.common.JspHelper;
import org.apache.hadoop.hdfs.server.datanode.DataNode;
import org.apache.hadoop.hdfs.server.datanode.DatanodeJspHelper;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.util.ServletUtil;
import org.znerd.xmlenc.XMLOutputter;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.URL;
/**
* Servlets for file checksum
*/
@InterfaceAudience.Private
public class FileChecksumServlets {
/**
* Redirect file checksum queries to an appropriate datanode.
*/
@InterfaceAudience.Private
public static class RedirectServlet extends DfsServlet {
/**
* For java.io.Serializable
*/
private static final long serialVersionUID = 1L;
/**
* Create a redirection URL
*/
private URL createRedirectURL(UserGroupInformation ugi, DatanodeID host,
HttpServletRequest request, NameNode nn) throws IOException {
final String hostname =
host instanceof DatanodeInfo ? ((DatanodeInfo) host).getHostName() :
host.getIpAddr();
final String scheme = request.getScheme();
final int port = "https".equals(scheme) ? (Integer) getServletContext()
.getAttribute(DFSConfigKeys.DFS_DATANODE_HTTPS_PORT_KEY) :
host.getInfoPort();
final String encodedPath =
ServletUtil.getRawPath(request, "/fileChecksum");
String dtParam = "";
if (UserGroupInformation.isSecurityEnabled()) {
String tokenString =
ugi.getTokens().iterator().next().encodeToUrlString();
dtParam = JspHelper.getDelegationTokenUrlParam(tokenString);
}
String addr = nn.getNameNodeAddressHostPortString();
String addrParam =
JspHelper.getUrlParam(JspHelper.NAMENODE_ADDRESS, addr);
return new URL(scheme, hostname, port,
"/getFileChecksum" + encodedPath + '?' +
"ugi=" + ServletUtil.encodeQueryValue(ugi.getShortUserName()) +
dtParam + addrParam);
}
@Override
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
final ServletContext context = getServletContext();
final Configuration conf = NameNodeHttpServer.getConfFromContext(context);
final UserGroupInformation ugi = getUGI(request, conf);
final NameNode namenode =
NameNodeHttpServer.getNameNodeFromContext(context);
final DatanodeID datanode = NamenodeJspHelper.getRandomDatanode(namenode);
try {
response.sendRedirect(
createRedirectURL(ugi, datanode, request, namenode).toString());
} catch (IOException e) {
response.sendError(400, e.getMessage());
}
}
}
/**
* Get FileChecksum
*/
@InterfaceAudience.Private
public static class GetServlet extends DfsServlet {
/**
* For java.io.Serializable
*/
private static final long serialVersionUID = 1L;
@Override
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
final PrintWriter out = response.getWriter();
final String path =
ServletUtil.getDecodedPath(request, "/getFileChecksum");
final XMLOutputter xml = new XMLOutputter(out, "UTF-8");
xml.declaration();
final ServletContext context = getServletContext();
final DataNode datanode = (DataNode) context.getAttribute("datanode");
final Configuration conf = new HdfsConfiguration(datanode.getConf());
try {
final DFSClient dfs = DatanodeJspHelper
.getDFSClient(request, datanode, conf, getUGI(request, conf));
final MD5MD5CRC32FileChecksum checksum = dfs.getFileChecksum(path);
MD5MD5CRC32FileChecksum.write(xml, checksum);
} catch (IOException ioe) {
writeXml(ioe, path, xml);
} catch (InterruptedException e) {
writeXml(e, path, xml);
}
xml.endDocument();
}
}
}