app/com/vangav/vos_instagram/controllers/get_photo/HandlerGetPhoto.java

/**
 * "First, solve the problem. Then, write the code. -John Johnson"
 * "Or use Vangav M"
 * www.vangav.com
 * */

/**
 * MIT License
 *
 * Copyright (c) 2016 Vangav
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 * */

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 * Facebook Group: Vangav Open Source - Backend
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package com.vangav.vos_instagram.controllers.get_photo;

import java.nio.ByteBuffer;
import java.util.UUID;

import com.datastax.driver.core.ResultSet;
import com.vangav.backend.content.formatting.EncodingInl;
import com.vangav.backend.exceptions.BadRequestException;
import com.vangav.backend.exceptions.VangavException.ExceptionClass;
import com.vangav.backend.play_framework.request.Request;
import com.vangav.backend.play_framework.request.RequestJsonBody;
import com.vangav.backend.play_framework.request.response.ResponseBody;
import com.vangav.vos_instagram.cassandra_keyspaces.ig_blobs.PhotosBlobs;
import com.vangav.vos_instagram.common.Authenticator;
import com.vangav.vos_instagram.controllers.CommonPlayHandler;

/**
 * GENERATED using ControllersGeneratorMain.java
 */
/**
 * HandlerGetPhoto
 *   handles request-to-response processing
 *   also handles after response processing (if any)
 * */
public class HandlerGetPhoto extends CommonPlayHandler {

  private static final String kName = "GetPhoto";

  @Override
  protected String getName () {

    return kName;
  }

  @Override
  protected RequestJsonBody getRequestJson () {

    return new RequestGetPhoto();
  }

  @Override
  protected ResponseBody getResponseBody () {

    return new ResponseGetPhoto();
  }
  
  @Override
  protected Authenticator getRequestAuthenticator (
    final RequestJsonBody requestJsonBody) throws Exception {
    
    return
      new Authenticator(
        ((RequestGetPhoto)requestJsonBody).device_token,
        ((RequestGetPhoto)requestJsonBody).user_id,
        ((RequestGetPhoto)requestJsonBody).access_token);
  }

  @Override
  protected void processRequest (final Request request) throws Exception {

    // use the following request Object to process the request and set
    //   the response to be returned
    RequestGetPhoto requestGetPhoto =
      (RequestGetPhoto)request.getRequestJsonBody();
    
    // select photo from database
    
    ResultSet resultSet =
      PhotosBlobs.i().executeSyncSelect(
        UUID.fromString(requestGetPhoto.photo_id) );
    
    if (resultSet.isExhausted() == true) {
      
      throw new BadRequestException(
        408,
        1,
        "Photo with photo_id ["
          + requestGetPhoto.photo_id
          + "] doesn't exist, request issued by user_id ["
          + requestGetPhoto.user_id
          + "] from device_token ["
          + requestGetPhoto.device_token
          + "]",
        ExceptionClass.INVALID);
    }
    
    // Extract photo
    ByteBuffer photoByteBuffer =
      resultSet.one().getBytes(PhotosBlobs.kPhotoColumnName);
    
    // decode photo
    String photoString =
      EncodingInl.decodeStringFromByteBuffer(photoByteBuffer);

    // set response
    ((ResponseGetPhoto)request.getResponseBody() ).set(
      requestGetPhoto.request_tracking_id,
      photoString);
  }
}