branch-1.2/ambari-server/src/main/java/org/apache/ambari/server/api/services/BaseRequest.java

/**
 * 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.ambari.server.api.services;

import org.apache.ambari.server.api.predicate.InvalidQueryException;
import org.apache.ambari.server.api.predicate.PredicateCompiler;
import org.apache.ambari.server.api.resources.*;
import org.apache.ambari.server.api.services.parsers.JsonPropertyParser;
import org.apache.ambari.server.api.services.parsers.RequestBodyParser;
import org.apache.ambari.server.api.services.serializers.JsonSerializer;
import org.apache.ambari.server.api.services.serializers.ResultSerializer;
import org.apache.ambari.server.controller.internal.TemporalInfoImpl;
import org.apache.ambari.server.controller.spi.Predicate;
import org.apache.ambari.server.controller.spi.TemporalInfo;

import javax.ws.rs.core.HttpHeaders;
import javax.ws.rs.core.UriInfo;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * Request implementation.
 */
public abstract class BaseRequest implements Request {

  /**
   * URI information
   */
  private UriInfo m_uriInfo;

  /**
   * Http headers
   */
  private HttpHeaders m_headers;

  /**
   * Http Body
   */
  private String m_body;


  /**
   * Associated resource definition
   */
  private ResourceInstance m_resource;


  /**
   * Constructor.
   *
   * @param headers      http headers
   * @param body         http body
   * @param uriInfo      uri information
   * @param resource     associated resource definition
   */
  public BaseRequest(HttpHeaders headers, String body, UriInfo uriInfo, ResourceInstance resource) {

    m_headers  = headers;
    m_body     = body;
    m_uriInfo  = uriInfo;
    m_resource = resource;
  }

  @Override
  public ResourceInstance getResource() {
    return m_resource;
  }

  @Override
  public String getURI() {
    try {
      return URLDecoder.decode(m_uriInfo.getRequestUri().toASCIIString(), "UTF-8");
    } catch (UnsupportedEncodingException e) {
      throw new RuntimeException("Unable to decode URI: " + e, e);
    }
  }

  @Override
  public int getAPIVersion() {
    return 0;
  }

  @Override
  public Predicate getQueryPredicate() throws InvalidQueryException {
    String uri     = getURI();
    int    qsBegin = uri.indexOf("?");

    return (qsBegin == -1) ? null :
        getPredicateCompiler().compile(uri.substring(qsBegin + 1));
  }

  @Override
  public Map<String, TemporalInfo> getFields() {
    Map<String, TemporalInfo> mapProperties;
    String partialResponseFields = m_uriInfo.getQueryParameters().getFirst("fields");
    if (partialResponseFields == null) {
      mapProperties = Collections.emptyMap();
    } else {
      Set<String> setMatches = new HashSet<String>();
      // Pattern basically splits a string using ',' as the deliminator unless ',' is between '[' and ']'.
      // Actually, captures char sequences between ',' and all chars between '[' and ']' including ','.
      Pattern re = Pattern.compile("[^,\\[]*?\\[[^\\]]*?\\]|[^,]+");
      Matcher m = re.matcher(partialResponseFields);
      while (m.find()){
        for (int groupIdx = 0; groupIdx < m.groupCount() + 1; groupIdx++) {
          setMatches.add(m.group(groupIdx));
        }
      }

      mapProperties = new HashMap<String, TemporalInfo>(setMatches.size());
      for (String field : setMatches) {
        TemporalInfo temporalInfo = null;
        if (field.contains("[")) {
          String[] temporalData = field.substring(field.indexOf('[') + 1,
              field.indexOf(']')).split(",");
          field = field.substring(0, field.indexOf('['));
          long start = Long.parseLong(temporalData[0].trim());
          long end   = -1;
          long step  = -1;
          if (temporalData.length >= 2) {
            end = Long.parseLong(temporalData[1].trim());
            if (temporalData.length == 3) {
              step = Long.parseLong(temporalData[2].trim());
            }
          }
          temporalInfo = new TemporalInfoImpl(start, end, step);
        }
        mapProperties.put(field, temporalInfo);
      }
    }

    return mapProperties;
  }

  @Override
  public Map<String, List<String>> getHttpHeaders() {
    return m_headers.getRequestHeaders();
  }

  @Override
  public String getHttpBody() {
    return m_body;
  }

  @Override
  public Set<Map<String, Object>> getHttpBodyProperties() {
    return getHttpBodyParser().parse(getHttpBody());
  }

  @Override
  public ResultSerializer getResultSerializer() {
    return new JsonSerializer();
  }

  @Override
  public ResultPostProcessor getResultPostProcessor() {
    return new ResultPostProcessorImpl(this);
  }

  protected RequestBodyParser getHttpBodyParser() {
    return new JsonPropertyParser();
  }

  protected PredicateCompiler getPredicateCompiler() {
    return new PredicateCompiler();
  }
}