verbosify bad desision

.gitignore

@@ -0,0 +1,2 @@
+bin/
+obj/

Aggregators/BookAggregator.cs

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+using System;
+using example_csharp_app.Interfaces;
+using example_csharp_app.Models.Mapper;
+using example_csharp_app.Models.Request;
+using example_csharp_app.Models.Response;
+
+namespace example_csharp_app.Aggregators;
+
+public class BookAggregator : IBookAggregator
+{
+    private readonly IBookService _bookService;
+
+    public BookAggregator(IBookService bookService)
+    {
+        _bookService = bookService;
+    }
+
+    public async Task<BookOperationResponse> AddBookAsync(BookCreateRequest request)
+    {
+        var result = await _bookService.AddBookAsync(request.MapToModel());
+        return new BookOperationResponse()
+        {
+            IsSuccess = result > 0
+        };
+    }
+
+    public async Task<BookSingleResponse> GetBookAsync(Guid bookId)
+    {
+        var book = await _bookService.GetBookAsync(bookId);
+        return new BookSingleResponse()
+        {
+            Book = book
+        };
+    }
+
+    public async Task<BookListResponse> GetBookListAsync(BookFilterRequest request)
+    {
+        // should make separate filter object, but feel lazy
+        var bookList = await _bookService.GetBooksAsync(request);
+        return new BookListResponse()
+        {
+            Books = bookList  
+        };
+    }
+
+    public async Task<BookOperationResponse> RemoveBookAsync(Guid bookId)
+    {
+        var result = await _bookService.RemoveBookAsync(bookId);
+        return new BookOperationResponse()
+        {
+            IsSuccess = result > 0  
+        };
+    }
+
+    public async Task<BookOperationResponse> UpdateBookAsync(BookUpdateRequest request)
+    {
+        var result = await _bookService.UpdateBookAsync(request.Id, request.MapToModel());
+        return new BookOperationResponse()
+        {
+            IsSuccess = result > 0
+        };
+    }
+}

Controllers/BookController.cs

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+using example_csharp_app.Interfaces;
+using example_csharp_app.Models.Request;
+using example_csharp_app.Models.Response;
+using Microsoft.AspNetCore.Mvc;
+using Swashbuckle.AspNetCore.Annotations;
+
+namespace example_csharp_app.Controllers
+{
+    [Route("api/[controller]")]
+    [ApiController]
+    public class BookController : ControllerBase
+    {
+        private readonly IBookAggregator _bookAggregator;
+
+        public BookController(IBookAggregator bookAggregator)
+        {
+            _bookAggregator = bookAggregator;
+        }
+
+        [SwaggerResponse(200, "Получить список книг", typeof(BookListResponse))]
+        [HttpGet()]
+        public async Task<IActionResult> GetList([FromQuery]BookFilterRequest request)
+        {
+            var bookList = await _bookAggregator.GetBookListAsync(request);
+            return Ok(bookList);
+        }
+
+        [SwaggerResponse(200, "Получить список книг", typeof(BookSingleResponse))]
+        [HttpGet("{bookId}")]
+        public async Task<IActionResult> GetBook([FromRoute] Guid bookId)
+        {
+            var result = await _bookAggregator.GetBookAsync(bookId);
+            return Ok(result);
+        }
+
+        [SwaggerResponse(200, "Добавить книгу", typeof(BookOperationResponse))]
+        [HttpPost()]
+        public async Task<IActionResult> AddBook([FromBody]BookCreateRequest request)
+        {
+            var result = await _bookAggregator.AddBookAsync(request);
+            return Ok(result);
+        }
+
+        [SwaggerResponse(200, "Обновить книгу", typeof(BookOperationResponse))]
+        [HttpPut()]
+        public async Task<IActionResult> UpdateBook([FromBody]BookUpdateRequest request)
+        {
+            var result = await _bookAggregator.UpdateBookAsync(request);
+            return Ok(result);
+        }
+
+        [SwaggerResponse(200, "Удалить книгу", typeof(BookOperationResponse))]
+        [HttpDelete("{bookId}")]
+        public async Task<IActionResult> RemoveBook([FromRoute]Guid bookId)
+        {
+            var result = await _bookAggregator.RemoveBookAsync(bookId);
+            return Ok(result);
+        }
+    }
+}

Database/Connector/AppDbContext.cs

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+using example_csharp_app.Dto;
+using Microsoft.EntityFrameworkCore;
+using System;
+
+namespace example_app.Database.Connector;
+
+public class AppDbContext(DbContextOptions<AppDbContext> options) : DbContext(options)
+{
+    public DbSet<BookDto> Books { set; get; }
+
+    protected override void OnModelCreating(ModelBuilder builder)
+    {
+        base.OnModelCreating(builder);
+
+        builder.Entity<BookDto>()
+            .ToTable("Books")
+            .HasKey(x => x.Id);
+
+        builder.Entity<BookDto>()
+            .Property(x => x.Author)
+            .IsRequired();
+        builder.Entity<BookDto>()
+            .Property(x => x.Title)
+            .IsRequired();
+        builder.Entity<BookDto>()
+            .Property(x => x.YearPublished)
+            .IsRequired();
+        builder.Entity<BookDto>()
+            .Property(x => x.BookIndex)
+            .IsRequired();
+
+        builder.Entity<BookDto>()
+            .Property(x => x.BookIndex)
+            .HasColumnType("xml");
+    }
+}

Dto/BookDto.cs

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+using System;
+using System.ComponentModel.DataAnnotations;
+
+namespace example_csharp_app.Dto;
+
+public class BookDto
+{
+    // Для описания модели использовал fluent api в AppDbContext
+    public Guid Id { set; get; }
+    public string Title { set; get; } = string.Empty;
+    public string Author { set; get; } = string.Empty;
+    public DateTime YearPublished { set; get; }
+    public string BookIndex { set; get; } = string.Empty;
+}

ErrorLogMiddleware.cs

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+using System;
+
+namespace example_csharp_app;
+
+public class ErrorLogMiddleware
+{
+    private readonly RequestDelegate _next;
+
+    public ErrorLogMiddleware(RequestDelegate next)
+    {
+        _next = next;
+    }
+
+    public async Task Invoke(HttpContext httpContext, IConfiguration configuration)
+    {
+        try 
+        {
+            await _next(httpContext);
+            return;
+        } 
+        catch (Exception)
+        {
+            // todo: logme
+            httpContext.Response.StatusCode = 500;
+        }
+    }
+}

Filters/XmlAttributeFilter.cs

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+using System;
+using System.ComponentModel.DataAnnotations;
+using System.Windows.Markup;
+using System.Xml;
+
+namespace example_csharp_app.Filters;
+
+[AttributeUsage(AttributeTargets.Property | AttributeTargets.Field | AttributeTargets.Parameter, AllowMultiple = false)]
+public class XmlAttribute : ValidationAttribute
+{
+
+    public XmlAttribute(): base("Passed string is not XML")
+    {}
+
+    /// <summary>
+    ///     Override of <see cref="ValidationAttribute.IsValid(object)" />
+    /// </summary>
+    /// <param name="value">The value to test</param>
+    /// <returns>
+    ///     Returns <see langword="false" /> if the <paramref name="value" /> is null or an empty string.
+    ///     If <see cref="AllowEmptyStrings" /> then <see langword="true" /> is returned for empty strings.
+    /// </returns>
+    public override bool IsValid(object? value)
+    {
+        if (value is null || value is not string)
+        {
+            return false;
+        }
+
+        string possiblyXml = ((string)value).Trim();
+        if (!possiblyXml.StartsWith('<') && !possiblyXml.EndsWith('>')) 
+        {
+            return false;
+        }
+        XmlDocument xml = new XmlDocument();
+        try
+        {
+            xml.LoadXml(possiblyXml);
+        }
+        catch (XmlException e)
+        {
+            // logme?
+            return false;
+        }
+
+        return true;
+    }
+    
+}

Interfaces/IBookAggregator.cs

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+using System;
+using example_csharp_app.Models.Request;
+using example_csharp_app.Models.Response;
+
+namespace example_csharp_app.Interfaces;
+
+public interface IBookAggregator
+{
+    Task<BookListResponse> GetBookListAsync(BookFilterRequest request);
+    Task<BookSingleResponse> GetBookAsync(Guid bookId);
+    Task<BookOperationResponse> UpdateBookAsync(BookUpdateRequest request);
+    Task<BookOperationResponse> AddBookAsync(BookCreateRequest request);
+    Task<BookOperationResponse> RemoveBookAsync(Guid bookId);
+}

Interfaces/IBookRepository.cs

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+using System;
+using example_csharp_app.Dto;
+using example_csharp_app.Models.Request;
+
+namespace example_csharp_app.Interfaces;
+
+public interface IBookRepository
+{
+    Task<int> AddBookAsync(BookDto dto);
+    Task<int> RemoveBookAsync(BookDto dto);
+    Task<BookDto?> GetBookAsync(Guid bookId, bool enableEdit = true);
+    Task<IReadOnlyCollection<BookDto>> GetBookListAsync(BookFilterRequest request);
+    Task<int> UpdateBookAsync(BookDto dto);
+}

Interfaces/IBookService.cs

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+using System;
+using example_csharp_app.Models.Model;
+using example_csharp_app.Models.Request;
+
+namespace example_csharp_app.Interfaces;
+
+public interface IBookService
+{
+    Task<IReadOnlyCollection<BookModel>> GetBooksAsync(BookFilterRequest request);
+    Task<BookModel?> GetBookAsync(Guid bookId);
+    Task<int> UpdateBookAsync(Guid bookId, BookUpdateModel model);
+    Task<int> AddBookAsync(BookCreateModel model);
+    Task<int> RemoveBookAsync(Guid bookId);
+}

Migrations/20260925040202_init.Designer.cs

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+// <auto-generated />
+using System;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+using example_app.Database.Connector;
+
+#nullable disable
+
+namespace example_csharp_app.Migrations
+{
+    [DbContext(typeof(AppDbContext))]
+    [Migration("20260925040202_init")]
+    partial class init
+    {
+        /// <inheritdoc />
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "10.0.12")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("example_csharp_app.Dto.BookDto", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("uuid");
+
+                    b.Property<string>("Author")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<string>("BookIndex")
+                        .IsRequired()
+                        .HasColumnType("xml");
+
+                    b.Property<string>("Title")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<DateTime>("YearPublished")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("Books", (string)null);
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

Migrations/20260925040202_init.cs

@@ -0,0 +1,37 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace example_csharp_app.Migrations
+{
+    /// <inheritdoc />
+    public partial class init : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "Books",
+                columns: table => new
+                {
+                    Id = table.Column<Guid>(type: "uuid", nullable: false),
+                    Title = table.Column<string>(type: "text", nullable: false),
+                    Author = table.Column<string>(type: "text", nullable: false),
+                    YearPublished = table.Column<DateTime>(type: "timestamp with time zone", nullable: false),
+                    BookIndex = table.Column<string>(type: "xml", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_Books", x => x.Id);
+                });
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "Books");
+        }
+    }
+}

Migrations/AppDbContextModelSnapshot.cs

@@ -0,0 +1,53 @@
+// <auto-generated />
+using System;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+using example_app.Database.Connector;
+
+#nullable disable
+
+namespace example_csharp_app.Migrations
+{
+    [DbContext(typeof(AppDbContext))]
+    partial class AppDbContextModelSnapshot : ModelSnapshot
+    {
+        protected override void BuildModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "10.0.12")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("example_csharp_app.Dto.BookDto", b =>
+                {
+                    b.Property<Guid>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("uuid");
+
+                    b.Property<string>("Author")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<string>("BookIndex")
+                        .IsRequired()
+                        .HasColumnType("xml");
+
+                    b.Property<string>("Title")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<DateTime>("YearPublished")
+                        .HasColumnType("timestamp with time zone");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("Books", (string)null);
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

Models/Mapper/BookMapper.cs

@@ -0,0 +1,32 @@
+using System;
+using example_csharp_app.Dto;
+using example_csharp_app.Models.Model;
+
+namespace example_csharp_app.Models.Mapper;
+
+public static class BookMapper
+{
+    public static BookModel MapToModel(this BookDto dto)
+    {
+        return new BookModel()
+        {
+            Author = dto.Author,
+            BookIndex = dto.BookIndex,
+            Id = dto.Id,
+            Title = dto.Title,
+            YearPublished = dto.YearPublished
+        };
+    }
+
+    public static BookDto MapToDto(this BookCreateModel model)
+    {
+        return new BookDto()
+        {
+            Id = Guid.NewGuid(),
+            Author = model.Author,
+            BookIndex = model.BookIndex,
+            Title = model.Title,
+            YearPublished = model.YearPublished
+        };
+    }
+}

Models/Mapper/RequestMapper.cs

@@ -0,0 +1,30 @@
+using System;
+using example_csharp_app.Models.Model;
+using example_csharp_app.Models.Request;
+
+namespace example_csharp_app.Models.Mapper;
+
+public static class RequestMapper
+{
+    public static BookCreateModel MapToModel(this BookCreateRequest request)
+    {
+        return new BookCreateModel()
+        {
+            Author = request.Author,
+            BookIndex = request.BookIndex.Trim(),
+            Title = request.Title,
+            YearPublished = request.YearPublished
+        };
+    }
+
+    public static BookUpdateModel MapToModel(this BookUpdateRequest request)
+    {
+        return new BookUpdateModel()
+        {
+            Author = request.Author,
+            BookIndex = request.BookIndex.Trim(),
+            Title = request.Title,
+            YearPublished = request.YearPublished
+        };
+    }
+}

Models/Model/BookCreateModel.cs

@@ -0,0 +1,11 @@
+using System;
+
+namespace example_csharp_app.Models.Model;
+
+public class BookCreateModel
+{
+    public string Title { set; get; } = string.Empty;
+    public string Author { set; get; } = string.Empty;
+    public DateTime YearPublished { set; get; }
+    public string BookIndex { set; get; } = string.Empty;
+}

Models/Model/BookModel.cs

@@ -0,0 +1,12 @@
+using System;
+
+namespace example_csharp_app.Models.Model;
+
+public class BookModel
+{
+    public Guid Id { set; get; }
+    public string Title { set; get; } = string.Empty;
+    public string Author { set; get; } = string.Empty;
+    public DateTime YearPublished { set; get; }
+    public string BookIndex { set; get; } = string.Empty;
+}

Models/Model/BookUpdateModel.cs

@@ -0,0 +1,11 @@
+using System;
+
+namespace example_csharp_app.Models.Model;
+
+public class BookUpdateModel
+{
+    public string Title { set; get; } = string.Empty;
+    public string Author { set; get; } = string.Empty;
+    public DateTime YearPublished { set; get; }
+    public string BookIndex { set; get; } = string.Empty;
+}

Models/Request/BookCreateRequest.cs

@@ -0,0 +1,17 @@
+using System;
+using System.ComponentModel.DataAnnotations;
+using example_csharp_app.Filters;
+
+namespace example_csharp_app.Models.Request;
+
+public class BookCreateRequest
+{
+    [Required]
+    public string Title { set; get; } = string.Empty;
+    [Required]
+    public string Author { set; get; } = string.Empty;
+    [Required]
+    public DateTime YearPublished { set; get; }
+    [Required, Xml]
+    public string BookIndex { set; get; } = string.Empty;
+}

Models/Request/BookFilterRequest.cs

@@ -0,0 +1,10 @@
+using System;
+
+namespace example_csharp_app.Models.Request;
+
+public class BookFilterRequest
+{
+    public string? Author { set; get; }
+    public string? Index { set; get; }
+    public string? Title { set; get; }
+}

Models/Request/BookUpdateRequest.cs

@@ -0,0 +1,19 @@
+using System;
+using System.ComponentModel.DataAnnotations;
+using example_csharp_app.Filters;
+
+namespace example_csharp_app.Models.Request;
+
+public class BookUpdateRequest
+{
+    [Required]
+    public Guid Id { set; get; } = Guid.Empty;
+    [Required]
+    public string Title { set; get; } = string.Empty;
+    [Required]
+    public string Author { set; get; } = string.Empty;
+    [Required]
+    public DateTime YearPublished { set; get; }
+    [Required, Xml]
+    public string BookIndex { set; get; } = string.Empty;
+}

Models/Response/BookListResponse.cs

@@ -0,0 +1,9 @@
+using System;
+using example_csharp_app.Models.Model;
+
+namespace example_csharp_app.Models.Response;
+
+public class BookListResponse
+{
+    public IReadOnlyCollection<BookModel> Books { set; get; } = [];
+}

Models/Response/BookOperationResponse.cs

@@ -0,0 +1,8 @@
+using System;
+
+namespace example_csharp_app.Models.Response;
+
+public class BookOperationResponse
+{
+    public bool IsSuccess { set; get; }
+}

Models/Response/BookSingleResponse.cs

@@ -0,0 +1,9 @@
+using System;
+using example_csharp_app.Models.Model;
+
+namespace example_csharp_app.Models.Response;
+
+public class BookSingleResponse
+{
+    public BookModel? Book { set; get; }
+}

Program.cs

@@ -0,0 +1,83 @@
+
+using example_app.Database.Connector;
+using example_csharp_app;
+using example_csharp_app.Aggregators;
+using example_csharp_app.Interfaces;
+using example_csharp_app.Repositories;
+using example_csharp_app.Services;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+
+
+namespace Program 
+{
+    public static class Program
+    {
+        private static void SetupDi(IServiceCollection services, IConfiguration configuration)
+        {
+            services.AddCors();
+
+            services.AddScoped<IBookAggregator, BookAggregator>();
+            services.AddScoped<IBookService, BookService>();
+            services.AddScoped<IBookRepository, BookRepository>();
+            services.AddDbContext<AppDbContext>(
+                (provider, builder) => 
+                {
+                    //var settings = provider.GetRequiredService<IOptions<DbSettings>>(); // эта версия лучше
+                    var connectionString = configuration.GetValue<string>("ConnectionStrings:DefaultConnection");
+                    builder.UseNpgsql(connectionString);
+                }, 
+                ServiceLifetime.Transient
+            );
+        }
+
+        public static int Main(string[] args)
+        {
+            try
+            {
+                var configurationBuilder = (new ConfigurationBuilder())
+                                            .SetBasePath(Environment.CurrentDirectory)
+                                            .AddJsonFile("appsettings.json", false, true)
+                                            .AddJsonFile("appsettings.{environmentName}", true, true)
+                                            .AddEnvironmentVariables()
+                                            .AddCommandLine(args);
+
+                var builder = WebApplication.CreateBuilder(args);
+                var configuration = configurationBuilder.Build();
+                
+                builder.Services.AddControllers();
+                builder.Services.AddSwaggerGen();
+
+                SetupDi(builder.Services, configuration);
+                
+            
+                var app = builder.Build();
+                //if(app.Environment.IsDevelopment())
+                //{
+                    app.UseSwagger();
+                    app.UseSwaggerUI();
+                //}
+                app.MapControllers();
+                app.UseMiddleware<ErrorLogMiddleware>();
+                //app.UseHttpsRedirection();
+                
+                app.Run();
+
+            } catch (Exception)
+            {
+                // log
+            }
+            finally
+            {
+                // flush log
+            }
+
+            return 0;
+            
+        }
+    }
+}
+
+
+

Properties/launchSettings.json

@@ -0,0 +1,23 @@
+{
+  "$schema": "https://json.schemastore.org/launchsettings.json",
+  "profiles": {
+    "http": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": false,
+      "applicationUrl": "http://localhost:5222",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "https": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": false,
+      "applicationUrl": "https://localhost:7189;http://localhost:5222",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    }
+  }
+}

README.md

@@ -1,2 +1,2 @@
-# example-csharp-app
-
+# example-csharp-app
+

Repositories/BookRepository.cs

@@ -0,0 +1,75 @@
+using System;
+using example_app.Database.Connector;
+using example_csharp_app.Dto;
+using example_csharp_app.Interfaces;
+using Microsoft.EntityFrameworkCore;
+using System.Linq;
+using example_csharp_app.Models.Request;
+
+namespace example_csharp_app.Repositories;
+
+public class BookRepository : IBookRepository
+{
+    private readonly AppDbContext _dbContext;
+
+    public BookRepository(AppDbContext dbContext)
+    {
+        _dbContext = dbContext;
+    }
+
+    public async Task<int> AddBookAsync(BookDto dto)
+    {
+        _dbContext.Add(dto);
+        return await _dbContext.SaveChangesAsync();
+    }
+
+    public async Task<BookDto?> GetBookAsync(Guid bookId, bool enableEdit = true)
+    {
+        var query = _dbContext.Books.Where(x => x.Id == bookId);
+        if(enableEdit == false)
+        {
+            query = query.AsNoTracking();
+        }
+        return await query.FirstOrDefaultAsync();
+    }
+
+    public async Task<IReadOnlyCollection<BookDto>> GetBookListAsync(BookFilterRequest request)
+    {
+        IQueryable<BookDto> query = _dbContext.Books.AsNoTracking();
+        if(request.Author != null)
+        {
+            query = query.Where(x => x.Author.Contains(request.Author));
+        }
+        if(request.Title != null)
+        {
+            query = query.Where(x => x.Title.Contains(request.Title));
+        }
+        if(request.Index != null)
+        {
+            var interminentQuery = await query.ToListAsync();
+            return interminentQuery.Where(x => x.BookIndex.Contains(request.Index)).ToList(); 
+            // решение плохое, но для поиска более хорошего нужно время
+            // возможно, потребуется изменить тип поля, либо раскидывать xml по другим таблицам.
+            // также возможно что в TransactSql этот момент учтен и поиск будет работать нативно
+            // но TransactSql у меня не раскатан, а Postgre уже стоит и крутится; так быстрее и проще в текущей ситуации
+
+            // xml ~~ xml - operation does not exist
+            //query = query.Where(x => x.BookIndex.Contains(request.Index));
+        }
+
+        return await query.ToListAsync(); // можно возвращать query как IEnumerable, но в некоторых случаях это будет приводить к исключению
+                                            // например если контекст инжектится фабрикой
+    }
+
+    public async Task<int> RemoveBookAsync(BookDto dto)
+    {
+        _dbContext.Books.Remove(dto);
+        return await _dbContext.SaveChangesAsync();
+    }
+
+    public async Task<int> UpdateBookAsync(BookDto dto)
+    {
+        _dbContext.Books.Update(dto);
+        return await _dbContext.SaveChangesAsync();
+    }
+}

Services/BookService.cs

@@ -0,0 +1,61 @@
+using System;
+using example_csharp_app.Dto;
+using example_csharp_app.Interfaces;
+using example_csharp_app.Models.Mapper;
+using example_csharp_app.Models.Model;
+using example_csharp_app.Models.Request;
+
+namespace example_csharp_app.Services;
+
+public class BookService : IBookService
+{  
+    private readonly IBookRepository _bookRepository;
+
+    public BookService(IBookRepository bookRepository)
+    {
+        _bookRepository = bookRepository;
+    }
+
+    public async Task<int> AddBookAsync(BookCreateModel model)
+    {
+        var dto = model.MapToDto();
+        var result = await _bookRepository.AddBookAsync(dto);
+        return result;
+    }
+
+    public async Task<BookModel?> GetBookAsync(Guid bookId)
+    {
+        var result = await _bookRepository.GetBookAsync(bookId, enableEdit: false);
+        return result?.MapToModel();
+    }
+
+    public async Task<IReadOnlyCollection<BookModel>> GetBooksAsync(BookFilterRequest request)
+    {
+        var result = await _bookRepository.GetBookListAsync(request);
+        return result.Select(x => x.MapToModel()).ToList();
+    }
+
+    public async Task<int> RemoveBookAsync(Guid bookId)
+    {
+        var book = await GetBookForEdit(bookId);
+        return await _bookRepository.RemoveBookAsync(book);
+    }
+
+    public async Task<int> UpdateBookAsync(Guid bookId, BookUpdateModel model)
+    {
+        var book = await GetBookForEdit(bookId);
+        
+        book.Author = model.Author;
+        book.BookIndex = model.BookIndex;
+        book.Title = model.Title;
+        book.YearPublished = model.YearPublished;
+
+        return await _bookRepository.UpdateBookAsync(book);
+    }
+
+    private async Task<BookDto> GetBookForEdit(Guid bookId)
+    {
+        var book = await _bookRepository.GetBookAsync(bookId);
+        return book ?? throw new ArgumentException();
+    }
+}

example-csharp-app.csproj

@@ -0,0 +1,23 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <RootNamespace>example_csharp_app</RootNamespace>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.EntityFrameworkCore" Version="10.0.12" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="10.0.12" />
+    <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="10.0.3" />
+    <PackageReference Include="Swashbuckle.AspNetCore" Version="10.2.3" />
+    <PackageReference Include="Swashbuckle.AspNetCore.SwaggerUI" Version="10.2.3" />
+    <PackageReference Include="Microsoft.Extensions.Configuration" Version="10.0.12" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.Binder" Version="10.0.12" />
+    <PackageReference Include="Swashbuckle.AspNetCore.Swagger" Version="10.2.3" />
+    <PackageReference Include="Swashbuckle.AspNetCore.SwaggerGen" Version="10.2.3" />
+    <PackageReference Include="Swashbuckle.AspNetCore.Annotations" Version="10.2.3" />
+  </ItemGroup>
+
+</Project>