ErrorResponseBuilder.java

/*
   Copyright (c) 2012 LinkedIn Corp.

   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.
 */

/**
 * $Id: $
 */

package com.linkedin.restli.internal.server.response;


import com.linkedin.data.template.RecordTemplate;
import com.linkedin.r2.message.rest.RestRequest;
import com.linkedin.restli.common.EmptyRecord;
import com.linkedin.restli.common.ErrorDetails;
import com.linkedin.restli.common.ErrorResponse;
import com.linkedin.restli.common.ProtocolVersion;
import com.linkedin.restli.common.ResourceMethod;
import com.linkedin.restli.common.RestConstants;
import com.linkedin.restli.internal.common.HeaderUtil;
import com.linkedin.restli.internal.common.ProtocolVersionUtil;
import com.linkedin.restli.internal.server.RoutingResult;
import com.linkedin.restli.server.ErrorResponseFormat;
import com.linkedin.restli.server.RestLiResponseData;
import com.linkedin.restli.server.RestLiServiceException;

import java.io.PrintWriter;
import java.io.StringWriter;
import java.net.HttpCookie;
import java.util.Collections;
import java.util.List;
import java.util.Map;


/**
 * @author Josh Walker
 * @version $Revision: $
 */
public final class ErrorResponseBuilder implements RestLiResponseBuilder
{
  public static final String DEFAULT_INTERNAL_ERROR_MESSAGE = "INTERNAL SERVER ERROR";
  private final ErrorResponseFormat _errorResponseFormat;
  private final String _internalErrorMessage;

  public ErrorResponseBuilder()
  {
    this(ErrorResponseFormat.defaultFormat());
  }

  public ErrorResponseBuilder(ErrorResponseFormat errorResponseFormat)
  {
    this(errorResponseFormat, DEFAULT_INTERNAL_ERROR_MESSAGE);
  }

  public ErrorResponseBuilder(ErrorResponseFormat errorResponseFormat, String internalErrorMessage)
  {
    _errorResponseFormat = errorResponseFormat;
    _internalErrorMessage = internalErrorMessage;
  }

  public String getInternalErrorMessage()
  {
    return _internalErrorMessage;
  }

  public ErrorResponse buildErrorResponse(RestLiServiceException result)
  {
    return buildErrorResponse(result, result.hasOverridingErrorResponseFormat() ? result.getOverridingFormat() : _errorResponseFormat);
  }

  private ErrorResponse buildErrorResponse(RestLiServiceException result, ErrorResponseFormat errorResponseFormat)
  {
    ErrorResponse er = new ErrorResponse();
    if (errorResponseFormat.showStatusCodeInBody())
    {
      er.setStatus(result.getStatus().getCode());
    }

    if (errorResponseFormat.showMessage() && result.getMessage() != null)
    {
      er.setMessage(result.getMessage());
    }
    if (errorResponseFormat.showServiceErrorCode() && result.hasServiceErrorCode())
    {
      er.setServiceErrorCode(result.getServiceErrorCode());
    }
    if (errorResponseFormat.showDetails() && result.hasErrorDetails())
    {
      er.setErrorDetails(new ErrorDetails(result.getErrorDetails()));
    }

    if (errorResponseFormat.showStacktrace())
    {
      StringWriter sw = new StringWriter();
      PrintWriter pw = new PrintWriter(sw);
      result.printStackTrace(pw);
      er.setStackTrace(sw.toString());

      er.setExceptionClass(result.getClass().getName());
    }

    if (errorResponseFormat.showExceptionClass())
    {
      er.setExceptionClass(result.getClass().getName());
    }

    return er;
  }

  @Override
  public PartialRestResponse buildResponse(RoutingResult routingResult, RestLiResponseData responseData)
  {
    ErrorResponse errorResponse = buildErrorResponse(responseData.getServiceException());
    return new PartialRestResponse.Builder().headers(responseData.getHeaders()).cookies(responseData.getCookies()).status(responseData.getStatus())
                                            .entity(errorResponse).build();
  }

  @Override
  public RestLiResponseData buildRestLiResponseData(RestRequest request,
                                                    RoutingResult routingResult,
                                                    Object object,
                                                    Map<String, String> headers,
                                                    List<HttpCookie> cookies)
  {
    RestLiServiceException exceptionResult = (RestLiServiceException) object;
    if (_errorResponseFormat.showHeaders())
    {
      final ProtocolVersion protocolVersion = ProtocolVersionUtil.extractProtocolVersion(headers);
      headers.put(HeaderUtil.getErrorResponseHeaderName(protocolVersion), RestConstants.HEADER_VALUE_ERROR);
    }
    final ResourceMethod type;
    if (routingResult != null && routingResult.getResourceMethod() != null)
    {
      type = routingResult.getResourceMethod().getMethodType();
    }
    else
    {
      RestLiResponseDataImpl responseData = new RestLiResponseDataImpl(exceptionResult, headers, cookies);
      return responseData;
    }

    RestLiResponseDataImpl responseData = new RestLiResponseDataImpl(exceptionResult, headers, cookies);
    responseData.setResponseEnvelope(EnvelopeBuilderUtil.buildBlankResponseEnvelope(type, responseData));

    return responseData;
  }
}