Abp.RelatedDtoLoader

An Abp module that help you automatically load related DTO (like ProductDto in OrderDto) under DDD.

Installation

1. Install the following NuGet packages. (see how)

   • EasyAbp.Abp.RelatedDtoLoader
   • EasyAbp.Abp.RelatedDtoLoader.Abstractions

2. Add DependsOn(typeof(AbpRelatedDtoLoaderModule)) attribute to configure the module dependencies. (see how)

Usage

1. Make your Order entity (or aggregate root) like this.

   public class Order : AggregateRoot<Guid>
   {
       public virtual Guid ProductId { get; protected set; }
   
       // do not add navigation properties to other aggregate roots!
       // public virtual Product Product { get; set; }
   
       protected Order() { }
   
       public Order(Guid id, Guid productId) : base(id)
       {
           ProductId = productId;
       }
   }

2. Add RelatedDto attribute in OrderDto.

   public class OrderDto : EntityDto<Guid>
   {
   	public Guid ProductId { get; set; }
   
   	//Automatic matching rules $"{nameof(Product)}Id"
   	[RelatedDto]
   	public ProductDto Product { get; set; }
   
   	//Manually matching the ProductId
   	[RelatedDto(nameof(ProductId))]
   	public ProductDto ProductInfo { get; set; }
   }

3. Create MyProjectRelatedDtoLoaderProfile and add a rule.

   public class MyProjectRelatedDtoLoaderProfile : RelatedDtoLoaderProfile
   {
   	public MyRelatedDtoLoaderProfile()
   	{
   		// the following example gets entities from a repository and maps them to DTOs.
   		UseRepositoryLoader<ProductDto, Product>();
   
   		// or load it by a customized function.
   		UseLoader(GetOrderDtosAsync);
   
   		// a target type need to be enabled to load its related Dtos properties.
   		// LoadForDto<OrderDto>();
   	}
   }

4. Configure the RelatedDtoLoader to use the profile.

   public override void ConfigureServices(ServiceConfigurationContext context)
   {
   	// ...
   
   	Configure<RelatedDtoLoaderOptions>(options =>
   	{
   		// add the Profile
   		options.AddProfile<MyProjectRelatedDtoLoaderProfile>();
   	});
   
   	// ...
   }

5. Enable the target type to load its related Dto properties.

   either in the Profile

   public class MyProjectRelatedDtoLoaderProfile : RelatedDtoLoaderProfile
   {
   	public MyRelatedDtoLoaderProfile()
   	{
   		// ...
   
   		// a target type need to be enabled to load its related Dtos properties.
   		LoadForDto<OrderDto>();
   	}
   }

   or via RegisterTargetDtosInModule method of RelatedDtoLoaderOptions

   public override void ConfigureServices(ServiceConfigurationContext context)
   {
   	// ...
   
   	Configure<RelatedDtoLoaderOptions>(options =>
   	{                                
   		// adding module will auto register all the target dto types which contain any property with RelatedDto attribute.
   		options.LoadForDtosInModule<MyApplicationContractsModule>();
   	});
   
   	// ...
   }

6. Try to get OrderDto with ProductDto.

   public class OrderAppService : ApplicationService, IOrderAppService
   {
   	private readonly IRelatedDtoLoader _relatedDtoLoader;
   	private readonly IRepository<Order, Guid> _orderRepository;
   
   	public OrderAppService(IRelatedDtoLoader relatedDtoLoader, IRepository<Order, Guid> orderRepository)
   	{
   		_relatedDtoLoader = relatedDtoLoader;
   		_orderRepository = orderRepository;
   	}
   
   	public async Task<OrderDto> GetAsync(Guid id)
   	{
   		var order = await _orderRepository.GetAsync(id);
   
   		var orderDto = ObjectMapper.Map<Order, OrderDto>(order);
   
   		//LoadAsync
   		return await _relatedDtoLoader.LoadAsync(orderDto);   // orderDto.Product should have been loaded.
   	}
   	
   	protected override async Task<List<OrderDto>> MapToGetListOutputDtosAsync(List<Order> entities)
   	{
   		var orderDtos = await base.MapToGetListOutputDtosAsync(entities);
   		
   		//LoadListAsync
   		return (await _relatedDtoLoader.LoadListAsync(orderDtos)).ToList(); // OrderDto.Product should have been loaded.
   	}
   }

See more: Custom DTO source examples.

Roadmap

• Custom DTO source
• Support one-to-many relation
• Support non Guid keys
• Support multi module development
• Support nested DTOs loading
• Get duplicate DTO from memory
• DTO cache
• An option to enable loading deleted DTO
• Unit test

Thanks @wakuflair and @itryan for their contribution in the first version.