Add initial implementation of product management API

.gitignore

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+bin/
+obj/
+/packages/
+riderModule.iml
+/_ReSharper.Caches/

EndavaTask.Tests/EndavaTask.Tests.csproj

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+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <TargetFramework>net10.0</TargetFramework>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+        <IsPackable>false</IsPackable>
+    </PropertyGroup>
+
+    <ItemGroup>
+        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
+        <PackageReference Include="Moq" Version="4.20.72" />
+        <PackageReference Include="xunit" Version="2.9.0" />
+        <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2" />
+    </ItemGroup>
+
+    <ItemGroup>
+        <ProjectReference Include="..\EndavaTask\EndavaTask.csproj" />
+    </ItemGroup>
+
+</Project>

EndavaTask.Tests/EntityDtoMappingsTests.cs

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+using EndavaTask.Contracts;
+using EndavaTask.Dtos;
+using EndavaTask.Mappings;
+using EndavaTask.Models;
+using Xunit;
+
+namespace EndavaTask.Tests;
+
+public class EntityDtoMappingsTests
+{
+    [Fact]
+    public void Product_ToDto_And_ToEntity_Roundtrip_Works()
+    {
+        var entity = new Product
+        {
+            Id = Guid.NewGuid(),
+            Name = "Keyboard",
+            Price = 90m,
+            CategoryId = Guid.NewGuid()
+        };
+
+        var dto = entity.ToDto();
+        var mappedBack = dto.ToEntity();
+
+        Assert.Equal(entity.Id, dto.Id);
+        Assert.Equal(entity.Name, dto.Name);
+        Assert.Equal(entity.Price, dto.Price);
+        Assert.Equal(entity.CategoryId, dto.CategoryId);
+
+        Assert.Equal(entity.Id, mappedBack.Id);
+        Assert.Equal(entity.Name, mappedBack.Name);
+        Assert.Equal(entity.Price, mappedBack.Price);
+        Assert.Equal(entity.CategoryId, mappedBack.CategoryId);
+    }
+
+    [Fact]
+    public void Category_ToDto_And_ToEntity_Roundtrip_Works()
+    {
+        var entity = new Category
+        {
+            Id = Guid.NewGuid(),
+            Name = "Home",
+            Description = "Home essentials"
+        };
+
+        var dto = entity.ToDto();
+        var mappedBack = dto.ToEntity();
+
+        Assert.Equal(entity.Id, dto.Id);
+        Assert.Equal(entity.Name, dto.Name);
+        Assert.Equal(entity.Description, dto.Description);
+
+        Assert.Equal(entity.Id, mappedBack.Id);
+        Assert.Equal(entity.Name, mappedBack.Name);
+        Assert.Equal(entity.Description, mappedBack.Description);
+    }
+
+    [Fact]
+    public void PagedProducts_ToDto_MapsMetadataAndItems()
+    {
+        var paged = new PagedResult<Product>
+        {
+            Items =
+            [
+                new Product { Id = Guid.NewGuid(), Name = "Laptop", Price = 1200m, CategoryId = Guid.NewGuid() },
+                new Product { Id = Guid.NewGuid(), Name = "Monitor", Price = 300m, CategoryId = Guid.NewGuid() }
+            ],
+            PageNumber = 2,
+            PageSize = 2,
+            TotalCount = 5,
+            TotalPages = 3
+        };
+
+        var dtoPaged = paged.ToDto();
+
+        Assert.Equal(2, dtoPaged.Items.Count);
+        Assert.Equal(2, dtoPaged.PageNumber);
+        Assert.Equal(2, dtoPaged.PageSize);
+        Assert.Equal(5, dtoPaged.TotalCount);
+        Assert.Equal(3, dtoPaged.TotalPages);
+
+        var first = Assert.IsType<ProductDto>(dtoPaged.Items.First());
+        Assert.Equal("Laptop", first.Name);
+    }
+}

EndavaTask.Tests/InMemoryProductRepositoryTests.cs

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+using EndavaTask.Contracts;
+using EndavaTask.Data;
+using Xunit;
+
+namespace EndavaTask.Tests;
+
+public class InMemoryProductRepositoryTests
+{
+    private readonly InMemoryProductRepository _repository = new();
+
+    [Fact]
+    public void GetFilteredProducts_FiltersByNameCategoryAndPriceRange_WithPagination()
+    {
+        var filter = new ProductFilterQuery
+        {
+            Name = "mon",
+            CategoryId = Guid.Parse("aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"),
+            MinPrice = 200m,
+            MaxPrice = 350m
+        };
+
+        var result = _repository.GetFilteredProducts(filter, new PaginationQuery { PageNumber = 1, PageSize = 10 });
+
+        Assert.Single(result.Items);
+        
+        var product = Assert.Single(result.Items);
+        
+        Assert.Equal("Monitor", product.Name);
+        Assert.Equal(1, result.TotalCount);
+        Assert.Equal(1, result.TotalPages);
+    }
+
+    [Fact]
+    public void GetFilteredProducts_ReturnsPagedData_WhenNoFilters()
+    {
+        var result = _repository.GetFilteredProducts(new ProductFilterQuery(), new PaginationQuery { PageNumber = 2, PageSize = 2 });
+
+        Assert.Equal(2, result.Items.Count);
+        Assert.Equal(5, result.TotalCount);
+        Assert.Equal(3, result.TotalPages);
+        Assert.Equal(2, result.PageNumber);
+        Assert.Equal(2, result.PageSize);
+    }
+}

EndavaTask.Tests/ProductServiceTests.cs

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+using EndavaTask.Contracts;
+using EndavaTask.Data;
+using EndavaTask.Dtos;
+using EndavaTask.Exceptions;
+using EndavaTask.Models;
+using EndavaTask.Services;
+using Moq;
+using Xunit;
+
+namespace EndavaTask.Tests;
+
+public class ProductServiceTests
+{
+    [Fact]
+    public void GetProducts_WithRepositoryResult_MapsAndReturnsPagedResult()
+    {
+        var categoryId = Guid.Parse("aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa");
+        var repositoryMock = new Mock<IProductRepository>();
+        
+        repositoryMock
+            .Setup(r => r.CategoryExists(categoryId))
+            .Returns(true);
+        
+        repositoryMock
+            .Setup(r => r.GetFilteredProducts(It.IsAny<ProductFilterQuery>(), It.IsAny<PaginationQuery>()))
+            .Returns(new PagedResult<Product>
+            {
+                Items =
+                [
+                    new Product { Id = Guid.NewGuid(), Name = "Laptop", Price = 1200m, CategoryId = categoryId },
+                    new Product { Id = Guid.NewGuid(), Name = "Headphones", Price = 180m, CategoryId = categoryId }
+                ],
+                PageNumber = 1,
+                PageSize = 2,
+                TotalCount = 3,
+                TotalPages = 2
+            });
+
+        var service = new ProductService(repositoryMock.Object);
+        var result = service.GetProducts(new ProductFilterQuery { CategoryId = categoryId }, new PaginationQuery { PageNumber = 1, PageSize = 2 });
+        var value = Assert.IsType<PagedResult<ProductDto>>(result);
+
+        Assert.Equal(2, value.Items.Count);
+        Assert.Equal(3, value.TotalCount);
+        Assert.Equal(2, value.TotalPages);
+    }
+
+    [Fact]
+    public void UpdateProduct_WithRepositoryEntity_ReturnsMappedDto()
+    {
+        var productId = Guid.Parse("55555555-5555-5555-5555-555555555555");
+        var categoryId = Guid.Parse("aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa");
+        
+        var repositoryMock = new Mock<IProductRepository>();
+        
+        repositoryMock
+            .Setup(r => r.UpdateProduct(productId, It.IsAny<UpdateProductRequest>()))
+            .Returns(new Product
+            {
+                Id = productId,
+                Name = "Updated Monitor",
+                Price = 350m,
+                CategoryId = categoryId
+            });
+
+        var service = new ProductService(repositoryMock.Object);
+        var result = service.UpdateProduct(productId, new UpdateProductRequest { Name = "Updated Monitor", Price = 350m });
+        var value = Assert.IsType<ProductDto>(result);
+
+        Assert.Equal("Updated Monitor", value.Name);
+        Assert.Equal(350m, value.Price);
+    }
+
+    [Fact]
+    public void GetProducts_WithUnknownCategory_ThrowsValidationException()
+    {
+        var repositoryMock = new Mock<IProductRepository>();
+        
+        repositoryMock
+            .Setup(r => r.CategoryExists(It.IsAny<Guid>()))
+            .Returns(false);
+
+        var service = new ProductService(repositoryMock.Object);
+
+        var exception = Assert.Throws<ApiValidationException>(() =>
+            service.GetProducts(new ProductFilterQuery { CategoryId = Guid.NewGuid() }, new PaginationQuery()));
+
+        Assert.True(exception.Errors.ContainsKey(nameof(ProductFilterQuery.CategoryId)));
+    }
+}

EndavaTask.sln

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+
+Microsoft Visual Studio Solution File, Format Version 12.00
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "EndavaTask", "EndavaTask\EndavaTask.csproj", "{56A4768E-E9F6-4C1B-8DDF-5BB907A84E15}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "EndavaTask.Tests", "EndavaTask.Tests\EndavaTask.Tests.csproj", "{C1248566-E881-41AE-9260-B943D0DC3BB1}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{56A4768E-E9F6-4C1B-8DDF-5BB907A84E15}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{56A4768E-E9F6-4C1B-8DDF-5BB907A84E15}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{56A4768E-E9F6-4C1B-8DDF-5BB907A84E15}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{56A4768E-E9F6-4C1B-8DDF-5BB907A84E15}.Release|Any CPU.Build.0 = Release|Any CPU
+		{C1248566-E881-41AE-9260-B943D0DC3BB1}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C1248566-E881-41AE-9260-B943D0DC3BB1}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C1248566-E881-41AE-9260-B943D0DC3BB1}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C1248566-E881-41AE-9260-B943D0DC3BB1}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+EndGlobal

EndavaTask/Contracts/PagedResult.cs

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+namespace EndavaTask.Contracts;
+
+/// <summary>
+/// Generic paged response container.
+/// </summary>
+public class PagedResult<T>
+{
+    /// <summary>
+    /// Items returned for the current page.
+    /// </summary>
+    public required IReadOnlyCollection<T> Items { get; init; }
+
+    /// <summary>
+    /// Current page number.
+    /// </summary>
+    public required int PageNumber { get; init; }
+
+    /// <summary>
+    /// Requested page size.
+    /// </summary>
+    public required int PageSize { get; init; }
+
+    /// <summary>
+    /// Total number of items matching the filter.
+    /// </summary>
+    public required int TotalCount { get; init; }
+
+    /// <summary>
+    /// Total number of pages for the current page size.
+    /// </summary>
+    public required int TotalPages { get; init; }
+}

EndavaTask/Contracts/PaginationQuery.cs

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+using System.ComponentModel.DataAnnotations;
+
+namespace EndavaTask.Contracts;
+
+/// <summary>
+/// Standard pagination query parameters.
+/// </summary>
+public class PaginationQuery
+{
+    /// <summary>
+    /// Page number to return, starting from 1.
+    /// </summary>
+    [Range(1, int.MaxValue)]
+    public int PageNumber { get; init; } = 1;
+
+    /// <summary>
+    /// Number of items per page. Max allowed value is 100.
+    /// </summary>
+    [Range(1, 100)]
+    public int PageSize { get; init; } = 10;
+}

EndavaTask/Contracts/ProductFilterQuery.cs

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+using System.ComponentModel.DataAnnotations;
+
+namespace EndavaTask.Contracts;
+
+/// <summary>
+/// Query parameters used to filter products.
+/// </summary>
+public class ProductFilterQuery : IValidatableObject
+{
+    /// <summary>
+    /// Returns products whose name contains this value (case-insensitive).
+    /// </summary>
+    [StringLength(100, MinimumLength = 1)]
+    public string? Name { get; init; }
+
+    /// <summary>
+    /// Returns products that belong to the specified category id.
+    /// </summary>
+    public Guid? CategoryId { get; init; }
+
+    /// <summary>
+    /// Minimum product price (inclusive).
+    /// </summary>
+    [Range(0, double.MaxValue)]
+    public decimal? MinPrice { get; init; }
+
+    /// <summary>
+    /// Maximum product price (inclusive).
+    /// </summary>
+    [Range(0, double.MaxValue)]
+    public decimal? MaxPrice { get; init; }
+
+    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
+    {
+        if (CategoryId.HasValue && CategoryId.Value == Guid.Empty)
+        {
+            yield return new ValidationResult(
+                "CategoryId must not be an empty GUID.",
+                [nameof(CategoryId)]);
+        }
+
+        if (MinPrice.HasValue && MaxPrice.HasValue && MinPrice.Value > MaxPrice.Value)
+        {
+            yield return new ValidationResult(
+                "MinPrice must be less than or equal to MaxPrice.",
+                [nameof(MinPrice), nameof(MaxPrice)]);
+        }
+    }
+}

EndavaTask/Contracts/UpdateProductRequest.cs

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+using System.ComponentModel.DataAnnotations;
+
+namespace EndavaTask.Contracts;
+
+/// <summary>
+/// Request payload for updating a product.
+/// </summary>
+public class UpdateProductRequest
+{
+    /// <summary>
+    /// New product name.
+    /// </summary>
+    [StringLength(100, MinimumLength = 1)]
+    public string? Name { get; init; }
+
+    /// <summary>
+    /// New product price.
+    /// </summary>
+    [Range(0, double.MaxValue)]
+    public decimal? Price { get; init; }
+}

EndavaTask/Controllers/ProductsController.cs

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+using EndavaTask.Contracts;
+using EndavaTask.Dtos;
+using EndavaTask.Services;
+using Microsoft.AspNetCore.Mvc;
+
+namespace EndavaTask.Controllers;
+
+[ApiController]
+[Route("api/v1/[controller]")]
+public class ProductsController(IProductService productService) : ControllerBase
+{
+    /// <summary>
+    /// Returns products filtered by optional criteria and paginated.
+    /// </summary>
+    /// <param name="filter">Filtering parameters such as name, category and price range.</param>
+    /// <param name="pagination">Pagination parameters.</param>
+    /// <returns>A paged list of products that match the filter.</returns>
+    [HttpGet]
+    [ProducesResponseType(typeof(PagedResult<ProductDto>), StatusCodes.Status200OK)]
+    [ProducesResponseType(typeof(ValidationProblemDetails), StatusCodes.Status400BadRequest)]
+    public ActionResult<PagedResult<ProductDto>> GetProducts([FromQuery] ProductFilterQuery filter, [FromQuery] PaginationQuery pagination)
+    {
+        return Ok(productService.GetProducts(filter, pagination));
+    }
+
+    /// <summary>
+    /// Updates an existing product's name and/or price.
+    /// </summary>
+    /// <param name="id">Product identifier.</param>
+    /// <param name="request">Fields to update.</param>
+    /// <returns>The updated product.</returns>
+    [HttpPut("{id:guid}")]
+    [ProducesResponseType(typeof(ProductDto), StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status404NotFound)]
+    [ProducesResponseType(typeof(ValidationProblemDetails), StatusCodes.Status400BadRequest)]
+    public ActionResult<ProductDto> UpdateProduct(Guid id, [FromBody] UpdateProductRequest request)
+    {
+        return Ok(productService.UpdateProduct(id, request));
+    }
+}

EndavaTask/Dtos/CategoryDto.cs

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+namespace EndavaTask.Dtos;
+
+/// <summary>
+/// Category data transfer object.
+/// </summary>
+public class CategoryDto
+{
+    /// <summary>
+    /// Unique category identifier.
+    /// </summary>
+    public Guid Id { get; init; }
+
+    /// <summary>
+    /// Category name.
+    /// </summary>
+    public required string Name { get; init; }
+
+    /// <summary>
+    /// Category description.
+    /// </summary>
+    public required string Description { get; init; }
+}

EndavaTask/Dtos/ProductDto.cs

@@ -0,0 +1,27 @@
+namespace EndavaTask.Dtos;
+
+/// <summary>
+/// Product data transfer object.
+/// </summary>
+public class ProductDto
+{
+    /// <summary>
+    /// Unique product identifier.
+    /// </summary>
+    public Guid Id { get; init; }
+
+    /// <summary>
+    /// Product name.
+    /// </summary>
+    public required string Name { get; init; }
+
+    /// <summary>
+    /// Product price.
+    /// </summary>
+    public decimal Price { get; init; }
+
+    /// <summary>
+    /// Identifier of the category this product belongs to.
+    /// </summary>
+    public Guid CategoryId { get; init; }
+}

EndavaTask/EndavaTask.csproj

@@ -0,0 +1,14 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+    <PropertyGroup>
+        <TargetFramework>net10.0</TargetFramework>
+        <Nullable>enable</Nullable>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <GenerateDocumentationFile>true</GenerateDocumentationFile>
+    </PropertyGroup>
+
+    <ItemGroup>
+        <PackageReference Include="Swashbuckle.AspNetCore" Version="6.6.2" />
+    </ItemGroup>
+
+</Project>

EndavaTask/EndavaTask.http

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+@EndavaTask_HostAddress = http://localhost:5262
+
+### Filter + paginate products
+GET {{EndavaTask_HostAddress}}/api/v1/products?name=mon&categoryId=aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa&minPrice=100&maxPrice=500&pageNumber=1&pageSize=10
+Accept: application/json
+
+### Update product name and/or price
+PUT {{EndavaTask_HostAddress}}/api/v1/products/55555555-5555-5555-5555-555555555555
+Content-Type: application/json
+
+{
+  "name": "Ultra Monitor",
+  "price": 349.99
+}

EndavaTask/Exceptions/ApiNotFoundException.cs

@@ -0,0 +1,3 @@
+namespace EndavaTask.Exceptions;
+
+public class ApiNotFoundException(string message) : Exception(message);

EndavaTask/Exceptions/ApiValidationException.cs

@@ -0,0 +1,6 @@
+namespace EndavaTask.Exceptions;
+
+public class ApiValidationException(IReadOnlyDictionary<string, string[]> errors) : Exception("Validation failed.")
+{
+    public IReadOnlyDictionary<string, string[]> Errors { get; } = errors;
+}

EndavaTask/Extensions/PaginationExtensions.cs

@@ -0,0 +1,27 @@
+using EndavaTask.Contracts;
+
+namespace EndavaTask.Extensions;
+
+public static class PaginationExtensions
+{
+    public static PagedResult<T> ToPagedResult<T>(this IEnumerable<T> source, PaginationQuery pagination)
+    {
+        var items = source.ToArray();
+        var totalCount = items.Length;
+        var totalPages = totalCount == 0 ? 0 : (int)Math.Ceiling(totalCount / (double)pagination.PageSize);
+
+        var pagedItems = items
+            .Skip((pagination.PageNumber - 1) * pagination.PageSize)
+            .Take(pagination.PageSize)
+            .ToArray();
+
+        return new PagedResult<T>
+        {
+            Items = pagedItems,
+            PageNumber = pagination.PageNumber,
+            PageSize = pagination.PageSize,
+            TotalCount = totalCount,
+            TotalPages = totalPages
+        };
+    }
+}

EndavaTask/Mappings/EntityDtoMappings.cs

@@ -0,0 +1,62 @@
+using EndavaTask.Contracts;
+using EndavaTask.Dtos;
+using EndavaTask.Models;
+
+namespace EndavaTask.Mappings;
+
+public static class EntityDtoMappings
+{
+    public static ProductDto ToDto(this Product entity)
+    {
+        return new ProductDto
+        {
+            Id = entity.Id,
+            Name = entity.Name,
+            Price = entity.Price,
+            CategoryId = entity.CategoryId
+        };
+    }
+
+    public static Product ToEntity(this ProductDto dto)
+    {
+        return new Product
+        {
+            Id = dto.Id,
+            Name = dto.Name,
+            Price = dto.Price,
+            CategoryId = dto.CategoryId
+        };
+    }
+
+    public static CategoryDto ToDto(this Category entity)
+    {
+        return new CategoryDto
+        {
+            Id = entity.Id,
+            Name = entity.Name,
+            Description = entity.Description
+        };
+    }
+
+    public static Category ToEntity(this CategoryDto dto)
+    {
+        return new Category
+        {
+            Id = dto.Id,
+            Name = dto.Name,
+            Description = dto.Description
+        };
+    }
+
+    public static PagedResult<ProductDto> ToDto(this PagedResult<Product> pagedResult)
+    {
+        return new PagedResult<ProductDto>
+        {
+            Items = pagedResult.Items.Select(i => i.ToDto()).ToArray(),
+            PageNumber = pagedResult.PageNumber,
+            PageSize = pagedResult.PageSize,
+            TotalCount = pagedResult.TotalCount,
+            TotalPages = pagedResult.TotalPages
+        };
+    }
+}

EndavaTask/Middleware/ExceptionHandlingMiddleware.cs

@@ -0,0 +1,72 @@
+using System.Text.Json;
+using EndavaTask.Exceptions;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.ModelBinding;
+
+namespace EndavaTask.Middleware;
+
+public class ExceptionHandlingMiddleware(RequestDelegate next, ILogger<ExceptionHandlingMiddleware> logger, IHostEnvironment environment)
+{
+    public async Task InvokeAsync(HttpContext context)
+    {
+        try
+        {
+            await next(context);
+        }
+        catch (Exception exception)
+        {
+            logger.LogError(exception, "Unhandled exception while processing {Method} {Path}", context.Request.Method, context.Request.Path);
+
+            var details = BuildProblemDetails(context, exception);
+
+            context.Response.StatusCode = details.Status ?? StatusCodes.Status500InternalServerError;
+            context.Response.ContentType = "application/problem+json";
+            details.Extensions["traceId"] = context.TraceIdentifier;
+
+            var json = JsonSerializer.Serialize(details);
+            await context.Response.WriteAsync(json);
+        }
+    }
+
+    private ProblemDetails BuildProblemDetails(HttpContext context, Exception exception)
+    {
+        switch (exception)
+        {
+            case ApiValidationException validationException:
+            {
+                var modelState = new ModelStateDictionary();
+                foreach (var error in validationException.Errors)
+                {
+                    foreach (var message in error.Value)
+                    {
+                        modelState.AddModelError(error.Key, message);
+                    }
+                }
+
+                return new ValidationProblemDetails(modelState)
+                {
+                    Status = StatusCodes.Status400BadRequest,
+                    Title = "Validation failed",
+                    Detail = "One or more validation errors occurred.",
+                    Instance = context.Request.Path
+                };
+            }
+            case ApiNotFoundException:
+                return new ProblemDetails
+                {
+                    Status = StatusCodes.Status404NotFound,
+                    Title = "Resource not found",
+                    Detail = exception.Message,
+                    Instance = context.Request.Path
+                };
+            default:
+                return new ProblemDetails
+                {
+                    Status = StatusCodes.Status500InternalServerError,
+                    Title = "Unexpected server error",
+                    Detail = environment.IsDevelopment() ? exception.Message : "An unexpected error occurred.",
+                    Instance = context.Request.Path
+                };
+        }
+    }
+}

EndavaTask/Middleware/ExceptionHandlingMiddlewareExtensions.cs

@@ -0,0 +1,9 @@
+namespace EndavaTask.Middleware;
+
+public static class ExceptionHandlingMiddlewareExtensions
+{
+    public static IApplicationBuilder UseGlobalExceptionHandling(this IApplicationBuilder app)
+    {
+        return app.UseMiddleware<ExceptionHandlingMiddleware>();
+    }
+}

EndavaTask/Models/Category.cs

@@ -0,0 +1,22 @@
+namespace EndavaTask.Models;
+
+/// <summary>
+/// Product category entity.
+/// </summary>
+public class Category
+{
+    /// <summary>
+    /// Unique category identifier.
+    /// </summary>
+    public Guid Id { get; init; }
+
+    /// <summary>
+    /// Category name.
+    /// </summary>
+    public required string Name { get; init; }
+
+    /// <summary>
+    /// Category description.
+    /// </summary>
+    public required string Description { get; init; }
+}

EndavaTask/Models/Product.cs

@@ -0,0 +1,27 @@
+namespace EndavaTask.Models;
+
+/// <summary>
+/// Product entity.
+/// </summary>
+public class Product
+{
+    /// <summary>
+    /// Unique product identifier.
+    /// </summary>
+    public Guid Id { get; init; }
+
+    /// <summary>
+    /// Product name.
+    /// </summary>
+    public required string Name { get; set; }
+
+    /// <summary>
+    /// Product price.
+    /// </summary>
+    public decimal Price { get; set; }
+
+    /// <summary>
+    /// Identifier of the category this product belongs to.
+    /// </summary>
+    public Guid CategoryId { get; init; }
+}

EndavaTask/Program.cs

@@ -0,0 +1,32 @@
+using System.Reflection;
+using EndavaTask.Data;
+using EndavaTask.Middleware;
+using EndavaTask.Services;
+
+var builder = WebApplication.CreateBuilder(args);
+
+builder.Services.AddControllers();
+builder.Services.AddEndpointsApiExplorer();
+builder.Services.AddSwaggerGen(options =>
+{
+    var xmlFileName = $"{Assembly.GetExecutingAssembly().GetName().Name}.xml";
+    var xmlPath = Path.Combine(AppContext.BaseDirectory, xmlFileName);
+    options.IncludeXmlComments(xmlPath);
+});
+builder.Services.AddSingleton<IProductRepository, InMemoryProductRepository>();
+builder.Services.AddScoped<IProductService, ProductService>();
+
+var app = builder.Build();
+
+if (app.Environment.IsDevelopment())
+{
+    app.UseSwagger();
+    app.UseSwaggerUI();
+}
+
+app.UseGlobalExceptionHandling();
+app.UseHttpsRedirection();
+app.UseAuthorization();
+app.MapControllers();
+
+app.Run();

EndavaTask/Properties/launchSettings.json

@@ -0,0 +1,25 @@
+{
+  "$schema": "https://json.schemastore.org/launchsettings.json",
+  "profiles": {
+    "http": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "launchUrl": "swagger",
+      "applicationUrl": "http://localhost:5262",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "https": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "launchUrl": "swagger",
+      "applicationUrl": "https://localhost:7079;http://localhost:5262",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    }
+  }
+}

EndavaTask/Repositories/InMemoryProductRepository.cs

@@ -0,0 +1,78 @@
+using EndavaTask.Contracts;
+using EndavaTask.Extensions;
+using EndavaTask.Models;
+
+namespace EndavaTask.Data;
+
+public class InMemoryProductRepository : IProductRepository
+{
+    private readonly List<Category> _categories =
+    [
+        new() { Id = Guid.Parse("aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"), Name = "Electronics", Description = "Devices and gadgets" },
+        new() { Id = Guid.Parse("bbbbbbbb-bbbb-bbbb-bbbb-bbbbbbbbbbbb"), Name = "Books", Description = "Printed and digital books" },
+        new() { Id = Guid.Parse("cccccccc-cccc-cccc-cccc-cccccccccccc"), Name = "Home", Description = "Home essentials" }
+    ];
+
+    private readonly List<Product> _products =
+    [
+        new() { Id = Guid.Parse("11111111-1111-1111-1111-111111111111"), Name = "Laptop", Price = 1200m, CategoryId = Guid.Parse("aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa") },
+        new() { Id = Guid.Parse("22222222-2222-2222-2222-222222222222"), Name = "Headphones", Price = 180m, CategoryId = Guid.Parse("aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa") },
+        new() { Id = Guid.Parse("33333333-3333-3333-3333-333333333333"), Name = "Clean Code", Price = 42m, CategoryId = Guid.Parse("bbbbbbbb-bbbb-bbbb-bbbb-bbbbbbbbbbbb") },
+        new() { Id = Guid.Parse("44444444-4444-4444-4444-444444444444"), Name = "Desk Lamp", Price = 35m, CategoryId = Guid.Parse("cccccccc-cccc-cccc-cccc-cccccccccccc") },
+        new() { Id = Guid.Parse("55555555-5555-5555-5555-555555555555"), Name = "Monitor", Price = 300m, CategoryId = Guid.Parse("aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa") }
+    ];
+
+    public PagedResult<Product> GetFilteredProducts(ProductFilterQuery filter, PaginationQuery pagination)
+    {
+        IEnumerable<Product> query = _products;
+
+        if (!string.IsNullOrWhiteSpace(filter.Name))
+        {
+            var nameFilter = filter.Name.Trim();
+            query = query.Where(p => p.Name.Contains(nameFilter, StringComparison.OrdinalIgnoreCase));
+        }
+
+        if (filter.CategoryId.HasValue)
+        {
+            query = query.Where(p => p.CategoryId == filter.CategoryId.Value);
+        }
+
+        if (filter.MinPrice.HasValue)
+        {
+            query = query.Where(p => p.Price >= filter.MinPrice.Value);
+        }
+
+        if (filter.MaxPrice.HasValue)
+        {
+            query = query.Where(p => p.Price <= filter.MaxPrice.Value);
+        }
+
+        return query.ToPagedResult(pagination);
+    }
+
+    public Product? UpdateProduct(Guid id, UpdateProductRequest request)
+    {
+        var product = _products.SingleOrDefault(p => p.Id == id);
+        if (product is null)
+        {
+            return null;
+        }
+
+        if (request.Name is not null)
+        {
+            product.Name = request.Name.Trim();
+        }
+
+        if (request.Price.HasValue)
+        {
+            product.Price = request.Price.Value;
+        }
+
+        return product;
+    }
+
+    public bool CategoryExists(Guid categoryId)
+    {
+        return _categories.Any(c => c.Id == categoryId);
+    }
+}

EndavaTask/Repositories/Interfaces/IProductRepository.cs

@@ -0,0 +1,11 @@
+using EndavaTask.Contracts;
+using EndavaTask.Models;
+
+namespace EndavaTask.Data;
+
+public interface IProductRepository
+{
+    PagedResult<Product> GetFilteredProducts(ProductFilterQuery filter, PaginationQuery pagination);
+    Product? UpdateProduct(Guid id, UpdateProductRequest request);
+    bool CategoryExists(Guid categoryId);
+}

EndavaTask/Services/Interfaces/IProductService.cs

@@ -0,0 +1,10 @@
+using EndavaTask.Contracts;
+using EndavaTask.Dtos;
+
+namespace EndavaTask.Services;
+
+public interface IProductService
+{
+    PagedResult<ProductDto> GetProducts(ProductFilterQuery filter, PaginationQuery pagination);
+    ProductDto UpdateProduct(Guid id, UpdateProductRequest request);
+}

EndavaTask/Services/ProductService.cs

@@ -0,0 +1,61 @@
+using EndavaTask.Contracts;
+using EndavaTask.Data;
+using EndavaTask.Dtos;
+using EndavaTask.Exceptions;
+using EndavaTask.Mappings;
+
+namespace EndavaTask.Services;
+
+public class ProductService(IProductRepository repository) : IProductService
+{
+    public PagedResult<ProductDto> GetProducts(ProductFilterQuery filter, PaginationQuery pagination)
+    {
+        var errors = new Dictionary<string, string[]>();
+
+        if (filter.MinPrice.HasValue && filter.MaxPrice.HasValue && filter.MinPrice > filter.MaxPrice)
+        {
+            errors[nameof(filter.MinPrice)] = ["MinPrice must be less than or equal to MaxPrice."];
+        }
+
+        if (filter.CategoryId.HasValue && !repository.CategoryExists(filter.CategoryId.Value))
+        {
+            errors[nameof(filter.CategoryId)] = ["CategoryId does not exist."];
+        }
+
+        if (errors.Count > 0)
+        {
+            throw new ApiValidationException(errors);
+        }
+
+        return repository.GetFilteredProducts(filter, pagination).ToDto();
+    }
+
+    public ProductDto UpdateProduct(Guid id, UpdateProductRequest request)
+    {
+        var errors = new Dictionary<string, string[]>();
+
+        if (request.Name is null && request.Price is null)
+        {
+            errors[string.Empty] = ["At least one field (name or price) must be provided."];
+        }
+
+        if (request.Name != null && string.IsNullOrWhiteSpace(request.Name))
+        {
+            errors[nameof(request.Name)] = ["Name cannot be empty."];
+        }
+
+        if (errors.Count > 0)
+        {
+            throw new ApiValidationException(errors);
+        }
+
+        var entity = repository.UpdateProduct(id, request);
+        
+        if (entity is null)
+        {
+            throw new ApiNotFoundException($"Product with id '{id}' was not found.");
+        }
+
+        return entity.ToDto();
+    }
+}

EndavaTask/appsettings.Development.json

@@ -0,0 +1,8 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  }
+}

EndavaTask/appsettings.json

@@ -0,0 +1,9 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "AllowedHosts": "*"
+}