content: /*
   * Copyright 2013 Agorava
   *
   * Licensed 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.agorava.oauth.helpers.extractors;
  
  import org.agorava.api.exception.OAuthParametersMissingException;
  import org.agorava.api.extractor.ExtractorType;
  import org.agorava.api.extractor.StringExtractor;
  import org.agorava.api.oauth.OAuthRequest;
  import org.agorava.api.rest.HttpParameters;
  import org.agorava.api.service.OAuthEncoder;
  import org.agorava.api.service.Preconditions;
  import org.agorava.rest.HttpParametersImpl;
  
  import static org.agorava.api.extractor.ExtractorType.Type.OAUTH1_BASE_STRING;
  
  /**
   * Default implementation of {@link org.agorava.api.extractor.StringExtractor}. Conforms to OAuth 1.0a
   *
   * @author Pablo Fernandez
   */
  @ExtractorType(OAUTH1_BASE_STRING)
  public class BaseStringExtractor implements StringExtractor {
  
      private static final String AMPERSAND_SEPARATED_STRING = "%s&%s&%s";
  
      /**
       * {@inheritDoc}
       */
      public String extract(OAuthRequest request) {
          checkPreconditions(request);
          String verb = OAuthEncoder.encode(request.getVerb().name());
          String url = OAuthEncoder.encode(request.getSanitizedUrl());
          String params = getSortedAndEncodedParams(request);
          return String.format(AMPERSAND_SEPARATED_STRING, verb, url, params);
      }
  
      private String getSortedAndEncodedParams(OAuthRequest request) {
          HttpParameters params = new HttpParametersImpl();
          params.addAll(request.getQueryStringParams());
          params.addAll(request.getBodyParams());
          params.addAll(new HttpParametersImpl(request.getOauthParameters()));
          return params.asOauthBaseString();
      }
  
      private void checkPreconditions(OAuthRequest request) {
          Preconditions.checkNotNull(request, "Cannot extract base string from null object");
  
          if (request.getOauthParameters() == null || request.getOauthParameters().size() <= 0) {
              throw new OAuthParametersMissingException(request);
          }
      }
  }
  