content: /*
   * 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.asterix.external.input.record.reader.http;
  
  import java.util.Collections;
  import java.util.List;
  import java.util.Map;
  
  import org.apache.asterix.common.exceptions.CompilationException;
  import org.apache.asterix.common.external.IExternalFilterEvaluatorFactory;
  import org.apache.asterix.external.api.IExternalDataRuntimeContext;
  import org.apache.asterix.external.api.IRecordReader;
  import org.apache.asterix.external.api.IRecordReaderFactory;
  import org.apache.asterix.external.util.ExternalDataConstants;
  import org.apache.asterix.external.util.FeedUtils;
  import org.apache.commons.lang3.tuple.Pair;
  import org.apache.hyracks.algebricks.common.constraints.AlgebricksAbsolutePartitionConstraint;
  import org.apache.hyracks.algebricks.common.exceptions.AlgebricksException;
  import org.apache.hyracks.api.application.IServiceContext;
  import org.apache.hyracks.api.exceptions.HyracksDataException;
  import org.apache.hyracks.api.exceptions.IWarningCollector;
  import org.apache.hyracks.http.server.HttpServerConfigBuilder;
  
  public class HttpServerRecordReaderFactory implements IRecordReaderFactory<char[]> {
      private static final long serialVersionUID = -66399726369366305L;
  
      private static final String KEY_CONFIGURATION_ADDRESSES = "addresses";
      private static final String KEY_CONFIGURATION_PATH = "path";
      private static final String KEY_CONFIGURATION_QUEUE_SIZE = "queue_size";
  
      private static final List<String> recordReaderNames =
              Collections.singletonList(ExternalDataConstants.KEY_ADAPTER_NAME_HTTP);
  
      private String entryPoint;
      private String addrValue;
      private int queueSize;
      private Map<String, String> configurations;
      private List<Pair<String, Integer>> serverAddrs;
  
      @Override
      public IRecordReader<? extends char[]> createRecordReader(IExternalDataRuntimeContext context)
              throws HyracksDataException {
          try {
              return new HttpServerRecordReader(serverAddrs.get(context.getPartition()).getRight(), entryPoint, queueSize,
                      HttpServerConfigBuilder.createDefault());
          } catch (Exception e) {
              throw HyracksDataException.create(e);
          }
      }
  
      @Override
      public Class<?> getRecordClass() {
          return char[].class;
      }
  
      @Override
      public List<String> getRecordReaderNames() {
          return recordReaderNames;
      }
  
      @Override
      public AlgebricksAbsolutePartitionConstraint getPartitionConstraint() {
          return FeedUtils.addressToAbsolutePartitionConstraints(serverAddrs);
      }
  
      private String getConfigurationValue(String key, boolean required) throws CompilationException {
          String value = configurations.get(key);
          if (value == null && required) {
              throw new CompilationException("Required configuration missing: " + key);
          }
          return value;
      }
  
      @Override
      public void configure(IServiceContext ctx, Map<String, String> configuration, IWarningCollector warningCollector,
              IExternalFilterEvaluatorFactory filterEvaluatorFactory) throws AlgebricksException {
          this.configurations = configuration;
          // necessary configs
          addrValue = getConfigurationValue(KEY_CONFIGURATION_ADDRESSES, true);
          serverAddrs = FeedUtils.extractHostsPorts(getConfigurationValue(ExternalDataConstants.KEY_MODE, true), ctx,
                  addrValue);
          // optional configs
          String queueSizeStr = getConfigurationValue(KEY_CONFIGURATION_QUEUE_SIZE, false);
          queueSize = queueSizeStr == null ? 0 : Integer.valueOf(queueSizeStr);
          entryPoint = getConfigurationValue(KEY_CONFIGURATION_PATH, false);
      }
  }
  