content: /*
   * Copyright 2010 Proofpoint, Inc.
   *
   * 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 io.airlift.http.client;
  
  import com.google.common.collect.ImmutableSet;
  import com.google.common.net.MediaType;
  import com.google.common.primitives.Ints;
  import io.airlift.json.JsonCodec;
  
  import java.util.Set;
  
  import static com.google.common.net.HttpHeaders.CONTENT_TYPE;
  import static io.airlift.http.client.ResponseHandlerUtils.propagate;
  import static io.airlift.http.client.ResponseHandlerUtils.readResponseBytes;
  import static java.nio.charset.StandardCharsets.UTF_8;
  
  public class JsonResponseHandler<T>
          implements ResponseHandler<T, RuntimeException>
  {
      private static final MediaType MEDIA_TYPE_JSON = MediaType.create("application", "json");
  
      public static <T> JsonResponseHandler<T> createJsonResponseHandler(JsonCodec<T> jsonCodec)
      {
          return new JsonResponseHandler<>(jsonCodec);
      }
  
      public static <T> JsonResponseHandler<T> createJsonResponseHandler(JsonCodec<T> jsonCodec, int firstSuccessfulResponseCode, int... otherSuccessfulResponseCodes)
      {
          return new JsonResponseHandler<>(jsonCodec, firstSuccessfulResponseCode, otherSuccessfulResponseCodes);
      }
  
      private final JsonCodec<T> jsonCodec;
      private final Set<Integer> successfulResponseCodes;
  
      private JsonResponseHandler(JsonCodec<T> jsonCodec)
      {
          this(jsonCodec, 200, 201, 202, 203, 204, 205, 206);
      }
  
      private JsonResponseHandler(JsonCodec<T> jsonCodec, int firstSuccessfulResponseCode, int... otherSuccessfulResponseCodes)
      {
          this.jsonCodec = jsonCodec;
          this.successfulResponseCodes = ImmutableSet.<Integer>builder().add(firstSuccessfulResponseCode).addAll(Ints.asList(otherSuccessfulResponseCodes)).build();
      }
  
      @Override
      public T handleException(Request request, Exception exception)
      {
          throw propagate(request, exception);
      }
  
      @Override
      public T handle(Request request, Response response)
      {
          if (!successfulResponseCodes.contains(response.getStatusCode())) {
              throw new UnexpectedResponseException(
                      String.format("Expected response code to be %s, but was %d", successfulResponseCodes, response.getStatusCode()),
                      request,
                      response);
          }
  
          String contentType = response.getHeader(CONTENT_TYPE);
          if (contentType == null) {
              throw new UnexpectedResponseException("Content-Type is not set for response", request, response);
          }
          if (!MediaType.parse(contentType).is(MEDIA_TYPE_JSON)) {
              throw new UnexpectedResponseException("Expected application/json response from server but got " + contentType, request, response);
          }
  
          byte[] bytes = readResponseBytes(request, response);
  
          try {
              return jsonCodec.fromJson(bytes);
          }
          catch (IllegalArgumentException e) {
              String json = new String(bytes, UTF_8);
              throw new IllegalArgumentException(String.format("Unable to create %s from JSON response: <%s>", jsonCodec.getType(), json), e);
          }
      }
  }
  