/**
    * 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.hbase.http;
  
  import java.util.HashMap;
  
  import org.apache.commons.logging.impl.Log4JLogger;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogConfigurationException;
  import org.apache.commons.logging.LogFactory;
  import org.apache.log4j.Appender;
  import org.apache.log4j.Logger;
  import org.mortbay.jetty.NCSARequestLog;
  import org.mortbay.jetty.RequestLog;
  
  /**
   * RequestLog object for use with Http
   */
  public class HttpRequestLog {
  
    private static final Log LOG = LogFactory.getLog(HttpRequestLog.class);
    private static final HashMap<String, String> serverToComponent;
  
    static {
      serverToComponent = new HashMap<String, String>();
      serverToComponent.put("master", "master");
      serverToComponent.put("region", "regionserver");
    }
  
    public static RequestLog getRequestLog(String name) {
  
      String lookup = serverToComponent.get(name);
      if (lookup != null) {
        name = lookup;
      }
      String loggerName = "http.requests." + name;
      String appenderName = name + "requestlog";
      Log logger = LogFactory.getLog(loggerName);
  
      if (logger instanceof Log4JLogger) {
        Log4JLogger httpLog4JLog = (Log4JLogger)logger;
        Logger httpLogger = httpLog4JLog.getLogger();
        Appender appender = null;
  
        try {
          appender = httpLogger.getAppender(appenderName);
        } catch (LogConfigurationException e) {
          LOG.warn("Http request log for " + loggerName
              + " could not be created");
          throw e;
        }
  
        if (appender == null) {
          LOG.info("Http request log for " + loggerName
              + " is not defined");
          return null;
        }
  
        if (appender instanceof HttpRequestLogAppender) {
          HttpRequestLogAppender requestLogAppender
            = (HttpRequestLogAppender)appender;
          NCSARequestLog requestLog = new NCSARequestLog();
          requestLog.setFilename(requestLogAppender.getFilename());
          requestLog.setRetainDays(requestLogAppender.getRetainDays());
          return requestLog;
        } else {
          LOG.warn("Jetty request log for " + loggerName
              + " was of the wrong class");
          return null;
        }
      }
      else {
        LOG.warn("Jetty request log can only be enabled using Log4j");
        return null;
      }
    }
  }