How to partial update entity - aspnetboilerplate

Question

May someone show an example with a partial update entity? All examples into git/docs/stack have only update method, which replaces all fields, even I sending null.
It looks like I need to use HttpPatch and json-patch. But it's so much extra code...
UserEntity
public class User: AbpUser<User>
{
[Required(AllowEmptyStrings = true)]
[StringLength(MaxNameLength)]
public override string Name { get; set; }
[Required(AllowEmptyStrings = true)]
[StringLength(MaxNameLength)]
public override string Surname { get; set; }
public string FatherName { get; set; }
public DateTime BirthDate { get; set; }
public long? DepartmentId { get; set; }
public long? ManagerId { get; set; }
public long? PositionId { get; set; }
public override string FullName => $"{Surname} {Name} {FatherName}";
}
CreateUserDto
{
"name": "Test",
"surname": "Test",
"emailAddress": "test#test.test"
}
UpdateUserDto
{
"id": 1,
"name": "Василий",
"surname": "Пупкин",
"fatherName": "Иванович",
"birthDate": "1993-02-21",
"emailAddress": "vasiliyp#test.test",
"phonenumber": "[phone]",
"departmentId": 1,
"positionId" : 1
}
Second UpdateUserDto
{
"id": 1,
"name": "Василий",
"surname": "Пупкин",
"fatherName": "Иванович"
}
After the second update I want to get a partial update, but it updates all fields include those I do not send. For example, PositionId will be null, instead of 1.
UserAppService
public override async Task<UserDto> UpdateAsync(UpdateUserDto input)
{
var user = await _userManager.GetUserByIdAsync(input.Id);
MapToEntity(input, user);
return await GetAsync(input);
}
protected override async void MapToEntity(UpdateUserDto input, User user)
{
ObjectMapper.Map(input, user);
user.SetNormalizedNames();
if (!user.DepartmentId.HasValue || user.DepartmentId == 0) return;
var department = await _departmentRepository.GetAsync((long)user.DepartmentId);
user.ManagerId = department.ManagerId;
}
Update
Yesterday I find a way: it needs to customize automapper that to merge models.
Configuration.Modules.AbpAutoMapper().Configurators.Add(
cfg => cfg.ForAllMaps((obj, cnfg) => cnfg.ForAllMembers(
opts => opts.Condition((src, dest, srcMember) => srcMember != null))));
But there are problems:
All value types into DTO must be nullable because the automapper will get default values.
Even though I have defined DateTime as nullable, the automatic conversion converts it to the default (DateTime). I have not yet found a way to fix this without a crutch.
if(input.BirthDate == null) input.BirthDate = user.BirthDate;
UPDATE 2
[AutoMapTo(typeof(User))]
public class UpdateUserDto : EntityDto<long>
{
[StringLength(AbpUserBase.MaxNameLength)]
public string Name { get; set; }
[StringLength(AbpUserBase.MaxSurnameLength)]
public string Surname { get; set; }
public string FatherName { get; set; }
public DateTime? BirthDate { get; set; }
[EmailAddress]
[StringLength(AbpUserBase.MaxEmailAddressLength)]
public string EmailAddress { get; set; }
public string PhoneNumber { get; set; }
public long? DepartmentId { get; set; }
public long? PositionId { get; set; }
}

Answer 1

you can create new Dto with specific fields and create new Update function for that.

Answer 2

As you have pointed out, all values in the update DTO must be declared nullable, or it will be assigned default values.
Then you also need to convert nullable type to using destination value instead.
// example for int, double and DateTime
CreateMap<int?, int>().ConvertUsing((src, dest) => src ?? dest);
CreateMap<double?, double>().ConvertUsing((src, dest) => src ?? dest);
CreateMap<DateTime?, DateTime>().ConvertUsing((src, dest) => src ?? dest);
// ignore if null
CreateMap<UpdateDTO, UpdateEntity>()
.ForAllMembers(opts => opts.Condition((src, dest, srcMember) => srcMember != null));