Unit of Work usage question [Answered]RSS

• • Reply
  cenk1536

  Member

  521 Points

  2685 Posts

  Unit of Work usage question

  Jul 01, 2019 07:29 AM|cenk1536|LINK

  Hello,

  I have a solution which has class libraries (business entities, business service, data models) and a web api project. I am using generic repository and unit of work. I am trying to implement my logic inside of business service as follows;

  using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Net;
  using System.Net.Http;
  using System.Threading.Tasks;
  using System.Transactions;
  using AutoMapper;
  using BusinessEntities;
  using BusinessService.Utility;
  using DataModels;
  using Newtonsoft.Json;
  
  namespace BusinessService
  {
      public class GameServices : IGameServices
      {
          private readonly UnitOfWork _unitOfWork;
  
          /// <summary>
          /// Public constructor.
          /// </summary>
          public GameServices(UnitOfWork unitOfWork)
          {
              _unitOfWork = unitOfWork;
          }
          
          /// <summary>
          /// Creates a product
          /// </summary>
          /// <param name="requestDto"></param>
          /// <returns></returns>
          public async Task<GameConfirmResponse> GamePurchase(RequestDto requestDto)
          {
              using (var scope = new TransactionScope())
              {
  
                  //Transform DTO into GameRequest for calling Razer Initiate
                  var config = new MapperConfiguration(cfg => {
                      cfg.CreateMap<RequestDto, GameRequest>();
                  });
                  var iMapper = config.CreateMapper();
                  var gameRequest = iMapper.Map<RequestDto, GameRequest>(requestDto);
                 
                  gameRequest = Utilities.CreateSignature(gameRequest, RequestType.Initiate);
                  //Unique reference ID
                  gameRequest.referenceId = Guid.NewGuid().ToString();
                  try
                  {
                      //Add request into database
                      _unitOfWork.GameRepository.Insert(gameRequest);
                  }
                  catch (Exception e)
                  {
                      
                      throw e;
                  }
                  
  
                  #region Call Razer initiate
  
                  var response = await Utilities.CallRazer(gameRequest, "purchaseinitiation");
                  //Read response
                  var htmlResponse = await response.Content.ReadAsStringAsync();
  
                  var gameResponse = JsonConvert.DeserializeObject<GameResponse>(htmlResponse);
                  //Adding response into database
                  _unitOfWork.GameResponseRepository.Insert(gameResponse);
                  
                  if (gameResponse.initiationResultCode == "00")
                  {
  
                  }
                  #endregion
                  await _unitOfWork.SaveAsync();
                  
                  var gameConfirmResponse = Mapper.Map<RequestDto, GameConfirmResponse>(requestDto);
                  scope.Complete();
                  
                  return gameConfirmResponse;
              }
          }
  
          
          public enum RequestType
          {
              Initiate = 0,
              Confirm = 1
              
          }
  
      }
  }
  

  I am getting this error; System.InvalidOperationException: The model backing the 'GameContext' context has changed since the database was created. Consider using Code First Migrations to update the database. My plan was to add changes to the database and at the end save all the changes once for all. What is the proper way to do it?

  Keep your friends close and your enemies even closer
• • Reply
  PatriceSc

  All-Star

  47220 Points

  17437 Posts

  Re: Unit of Work usage question

  Jul 01, 2019 07:41 AM|PatriceSc|LINK

  Hi,

  It is unrelated to updating data. It means you changed the GameContext without applying changes to the underlying database. See https://docs.microsoft.com/en-us/ef/ef6/modeling/code-first/migrations/

  You are using code first to define your db structure ?

• • Reply
  cenk1536

  Member

  521 Points

  2685 Posts

  Re: Unit of Work usage question

  Jul 01, 2019 07:47 AM|cenk1536|LINK

  yes PatriceSc, I am using code first approach.

  Here is my insert in generic repository.

  public virtual void Insert(TEntity entity)
          {
              dbSet.Add(entity);
          }

  I don't get it after every add should I use;

  await _unitOfWork.SaveAsync();

  I think there was a change in the table fields :)

  Keep your friends close and your enemies even closer