Add CRUDs and validation/controllers

src/Imprink.Application/Domains/Users/DeleteUserRoleHandler.cs

@@ -0,0 +1,43 @@
+using Imprink.Application.Exceptions;
+using Imprink.Application.Users.Dtos;
+using MediatR;
+
+namespace Imprink.Application.Domains.Users;
+
+public record DeleteUserRoleCommand(string Sub, Guid RoleId) : IRequest<UserRoleDto?>;
+
+public class DeleteUserRoleHandler(IUnitOfWork uw) : IRequestHandler<DeleteUserRoleCommand, UserRoleDto?>
+{
+    public async Task<UserRoleDto?> Handle(DeleteUserRoleCommand request, CancellationToken cancellationToken)
+    {
+        await uw.BeginTransactionAsync(cancellationToken);
+
+        try
+        {
+            if (!await uw.UserRepository.UserExistsAsync(request.Sub, cancellationToken))
+                throw new NotFoundException("User with ID: " + request.Sub + " does not exist.");
+
+            var existingUserRole = await uw.UserRoleRepository.GetUserRoleAsync(request.Sub, request.RoleId, cancellationToken);
+            
+            if (existingUserRole == null)
+                throw new NotFoundException($"User role not found for user {request.Sub} and role {request.RoleId}");
+
+            var removedRole = await uw.UserRoleRepository.RemoveUserRoleAsync(existingUserRole, cancellationToken);
+
+            await uw.SaveAsync(cancellationToken);
+            await uw.CommitTransactionAsync(cancellationToken);
+            
+            return new UserRoleDto
+            {
+                UserId = removedRole.UserId,
+                RoleId = removedRole.RoleId
+            };
+        }
+        catch
+        {
+            await uw.RollbackTransactionAsync(cancellationToken);
+            throw;
+        }
+        
+    }
+}