From b794eae22fc3b2d81b70ed1b2d0ea9c964e1bc9a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Halil=20=C4=B0brahim=20Kalkan?= Date: Wed, 22 Jul 2020 19:08:26 +0300 Subject: [PATCH] Update Part-10.md --- docs/en/Tutorials/Part-10.md | 222 ++++++++++++++++++++++++++++++++++- 1 file changed, 221 insertions(+), 1 deletion(-) diff --git a/docs/en/Tutorials/Part-10.md b/docs/en/Tutorials/Part-10.md index da2ba59bcb..6b934bacb8 100644 --- a/docs/en/Tutorials/Part-10.md +++ b/docs/en/Tutorials/Part-10.md @@ -228,4 +228,224 @@ You can now run the `.DbMigrator` console application to **seed** the initial da ## Application Layer -TODO \ No newline at end of file +We will change the `BookAppService` to support the Author relation. + +### Data Transfer Objects + +Let's begin from the DTOs. + +#### BookDto + +Open the `BookDto` class in the `Books` folder of the `Acme.BookStore.Application.Contracts` project and add the following properties: + +```csharp +public Guid AuthorId { get; set; } +public string AuthorName { get; set; } +``` + +The final `BookDto` class should be following: + +```csharp +using System; +using Volo.Abp.Application.Dtos; + +namespace Acme.BookStore.Books +{ + public class BookDto : AuditedEntityDto + { + public Guid AuthorId { get; set; } + + public string AuthorName { get; set; } + + public string Name { get; set; } + + public BookType Type { get; set; } + + public DateTime PublishDate { get; set; } + + public float Price { get; set; } + } +} +``` + +#### CreateUpdateBookDto + +Open the `CreateUpdateBookDto` class in the `Books` folder of the `Acme.BookStore.Application.Contracts` project and add an `AuthorId` property as shown: + +````csharp +public Guid AuthorId { get; set; } +```` + +#### AuthorLookupDto + +Create a new class, `AuthorLookupDto`, inside the `Books` folder of the `Acme.BookStore.Application.Contracts` project: + +````csharp +using System; +using Volo.Abp.Application.Dtos; + +namespace Acme.BookStore.Books +{ + public class AuthorLookupDto : EntityDto + { + public string Name { get; set; } + } +} +```` + +This will be used in a new method will be added to the `IBookAppService`. + +### IBookAppService + +Open the `IBookAppService` interface in the `Books` folder of the `Acme.BookStore.Application.Contracts` project and add a new method, named `GetAuthorLookupAsync`, as shown below: + +````csharp +using System; +using System.Threading.Tasks; +using Volo.Abp.Application.Dtos; +using Volo.Abp.Application.Services; + +namespace Acme.BookStore.Books +{ + public interface IBookAppService : + ICrudAppService< //Defines CRUD methods + BookDto, //Used to show books + Guid, //Primary key of the book entity + PagedAndSortedResultRequestDto, //Used for paging/sorting + CreateUpdateBookDto> //Used to create/update a book + { + // ADD the NEW METHOD + Task> GetAuthorLookupAsync(); + } +} +```` + +This new method will be used from the UI to get a list of authors and fill a dropdown list to select the author of a book. + +### BookAppService + +Open the `BookAppService` interface in the `Books` folder of the `Acme.BookStore.Application` project and replace the file content with the following code: + +```csharp +using System; +using System.Collections.Generic; +using System.Linq; +using System.Threading.Tasks; +using Acme.BookStore.Authors; +using Acme.BookStore.Permissions; +using Microsoft.AspNetCore.Authorization; +using Volo.Abp.Application.Dtos; +using Volo.Abp.Application.Services; +using Volo.Abp.Domain.Entities; +using Volo.Abp.Domain.Repositories; + +namespace Acme.BookStore.Books +{ + [Authorize(BookStorePermissions.Books.Default)] + public class BookAppService : + CrudAppService< + Book, //The Book entity + BookDto, //Used to show books + Guid, //Primary key of the book entity + PagedAndSortedResultRequestDto, //Used for paging/sorting + CreateUpdateBookDto>, //Used to create/update a book + IBookAppService //implement the IBookAppService + { + private readonly IAuthorRepository _authorRepository; + + public BookAppService( + IRepository repository, + IAuthorRepository authorRepository) + : base(repository) + { + _authorRepository = authorRepository; + GetPolicyName = BookStorePermissions.Books.Default; + GetListPolicyName = BookStorePermissions.Books.Default; + CreatePolicyName = BookStorePermissions.Books.Create; + UpdatePolicyName = BookStorePermissions.Books.Edit; + DeletePolicyName = BookStorePermissions.Books.Create; + } + + public override async Task GetAsync(Guid id) + { + //Prepare a query to join books and authors + var query = from book in Repository + join author in _authorRepository on book.AuthorId equals author.Id + where book.Id == id + select new { book, author }; + + //Execute the query and get the book with author + var queryResult = await AsyncExecuter.FirstOrDefaultAsync(query); + if (queryResult == null) + { + throw new EntityNotFoundException(typeof(Book), id); + } + + var bookDto = ObjectMapper.Map(queryResult.book); + bookDto.AuthorName = queryResult.author.Name; + return bookDto; + } + + public override async Task> + GetListAsync(PagedAndSortedResultRequestDto input) + { + //Prepare a query to join books and authors + var query = from book in Repository + join author in _authorRepository on book.AuthorId equals author.Id + orderby input.Sorting + select new {book, author}; + + query = query + .Skip(input.SkipCount) + .Take(input.MaxResultCount); + + //Execute the query and get a list + var queryResult = await AsyncExecuter.ToListAsync(query); + + //Convert the query result to a list of BookDto objects + var bookDtos = queryResult.Select(x => + { + var bookDto = ObjectMapper.Map(x.book); + bookDto.AuthorName = x.author.Name; + return bookDto; + }).ToList(); + + //Get the total count with another query + var totalCount = await Repository.GetCountAsync(); + + return new PagedResultDto( + totalCount, + bookDtos + ); + } + + public async Task> GetAuthorLookupAsync() + { + var authors = await _authorRepository.GetListAsync(); + + return new ListResultDto( + ObjectMapper.Map, List>(authors) + ); + } + } +} +``` + +Let's see the changes we've done: + +* Added `[Authorize(BookStorePermissions.Books.Default)]` to authorize the methods we've newly added/overrode (remember, authorize attribute is valid for all the methods of the class when it is declared for a class). +* Injected `IAuthorRepository` to query from the authors. +* Overrode the `GetAsync` method of the base `CrudAppService`, which returns a single `BookDto` object with the given `id`. + * Used a simple LINQ expression to join books and authors and query them together for the given book id. + * Used `AsyncExecuter.FirstOrDefaultAsync(...)` to execute the query and get a result. `AsyncExecuter` was previously used in the `AuthorAppService`. Check the [repository documentation](../Repositories.md) to understand why we've used it. + * Throws an `EntityNotFoundException` which results an `HTTP 404` (not found) result if requested book was not present in the database. + * Finally, created a `BookDto` object using the `ObjectMapper`, then assigning the `AuthorName` manually. +* Overrode the `GetListAsync` method of the base `CrudAppService`, which returns a list of books. The logic is similar to the previous method, so you can easily understand the code. +* Created a new method: `GetAuthorLookupAsync`. This simple gets all the authors. The UI uses this method to fill a dropdown list and select and author while creating/editing books. + + + + + +### Object to Object Mapping Configuration +