org.apache.hadoop.hdfs.qjournal.server.JournalNodeHttpServer.java Source code

Introduction

Here is the source code for org.apache.hadoop.hdfs.qjournal.server.JournalNodeHttpServer.java

Source

/**
 * 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.qjournal.server;

import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_ADMIN;
import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_JOURNALNODE_KEYTAB_FILE_KEY;
import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_JOURNALNODE_INTERNAL_SPNEGO_USER_NAME_KEY;

import java.io.IOException;
import java.net.InetSocketAddress;

import javax.servlet.ServletContext;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hdfs.DFSConfigKeys;
import org.apache.hadoop.hdfs.DFSUtil;
import org.apache.hadoop.hdfs.server.common.JspHelper;
import org.apache.hadoop.http.HttpServer;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.security.authorize.AccessControlList;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.security.SecurityUtil;

/**
 * Encapsulates the HTTP server started by the Journal Service.
 */
@InterfaceAudience.Private
public class JournalNodeHttpServer {
    public static final Log LOG = LogFactory.getLog(JournalNodeHttpServer.class);

    public static final String JN_ATTRIBUTE_KEY = "localjournal";

    private HttpServer httpServer;
    private int infoPort;
    private JournalNode localJournalNode;

    private final Configuration conf;

    JournalNodeHttpServer(Configuration conf, JournalNode jn) {
        this.conf = conf;
        this.localJournalNode = jn;
    }

    void start() throws IOException {
        final InetSocketAddress bindAddr = getAddress(conf);

        // initialize the webserver for uploading/downloading files.
        LOG.info("Starting web server as: " + SecurityUtil.getServerPrincipal(
                conf.get(DFS_JOURNALNODE_INTERNAL_SPNEGO_USER_NAME_KEY), bindAddr.getHostName()));

        int tmpInfoPort = bindAddr.getPort();
        httpServer = new HttpServer("journal", bindAddr.getHostName(), tmpInfoPort, tmpInfoPort == 0, conf,
                new AccessControlList(conf.get(DFS_ADMIN, " "))) {
            {
                if (UserGroupInformation.isSecurityEnabled()) {
                    initSpnego(conf, DFS_JOURNALNODE_INTERNAL_SPNEGO_USER_NAME_KEY,
                            DFSUtil.getSpnegoKeytabKey(conf, DFS_JOURNALNODE_KEYTAB_FILE_KEY));
                }
            }
        };
        httpServer.setAttribute(JN_ATTRIBUTE_KEY, localJournalNode);
        httpServer.setAttribute(JspHelper.CURRENT_CONF, conf);
        httpServer.addInternalServlet("getJournal", "/getJournal", GetJournalEditServlet.class, true);
        httpServer.start();

        // The web-server port can be ephemeral... ensure we have the correct info
        infoPort = httpServer.getPort();

        LOG.info("Journal Web-server up at: " + bindAddr + ":" + infoPort);
    }

    void stop() throws IOException {
        if (httpServer != null) {
            try {
                httpServer.stop();
            } catch (Exception e) {
                throw new IOException(e);
            }
        }
    }

    /**
     * Return the actual address bound to by the running server.
     */
    public InetSocketAddress getAddress() {
        InetSocketAddress addr = httpServer.getListenerAddress();
        assert addr.getPort() != 0;
        return addr;
    }

    private static InetSocketAddress getAddress(Configuration conf) {
        String addr = conf.get(DFSConfigKeys.DFS_JOURNALNODE_HTTP_ADDRESS_KEY,
                DFSConfigKeys.DFS_JOURNALNODE_HTTP_ADDRESS_DEFAULT);
        return NetUtils.createSocketAddr(addr, DFSConfigKeys.DFS_JOURNALNODE_HTTP_PORT_DEFAULT,
                DFSConfigKeys.DFS_JOURNALNODE_HTTP_ADDRESS_KEY);
    }

    public static Journal getJournalFromContext(ServletContext context, String jid) throws IOException {
        JournalNode jn = (JournalNode) context.getAttribute(JN_ATTRIBUTE_KEY);
        return jn.getOrCreateJournal(jid);
    }

    public static Configuration getConfFromContext(ServletContext context) {
        return (Configuration) context.getAttribute(JspHelper.CURRENT_CONF);
    }
}