get all categories

Diligent.WebAPI.Business/MappingProfiles/CategoryMappingProfile.cs

             #endregion
 
             #region Model to DTO
+            CreateMap<Category, TreeCategoryItem>();
             #endregion
         }
     }

Diligent.WebAPI.Business/Services/CategoryService.cs

 
             return dto;
         }
+
+        public async Task<List<TreeCategoryItem>> GetAllCategories()
+        {
+            var res = await _context.Categories.Include(k => k.ParentCategory).ToListAsync();
+            return _mapper.Map<List<TreeCategoryItem>>(res);
+        }
     }
 }

Diligent.WebAPI.Business/Services/Interfaces/ICategoryService.cs

         Task<CategoriesParentChild> GetRootCategories(int userId,int categoryId);
         Task<Category> GetCategoryEntityById(int? id);
         Task<List<IsGrantedCategory>> GetCategories(int userId);
+        Task<List<TreeCategoryItem>> GetAllCategories();
     }
 }

Diligent.WebAPI.Contracts/DTOs/Categories/TreeCategoryItem.cs

+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Diligent.WebAPI.Contracts.DTOs.Categories
+{
+    public class TreeCategoryItem
+    {
+        public int Id { get; set; }
+
+        public string Name { get; set; }
+        public TreeCategoryItem? ParentCategory { get; set; } = null;
+    }
+}

Diligent.WebAPI.Host/Controllers/V1/CategoriesController.cs

         [HttpGet("granted-categories")]
         public async Task<IActionResult> GetCategories(int userId) =>
             Ok(await _categoryService.GetCategories(userId));
+
+        [HttpGet("all-categories")]
+        public async Task<IActionResult> GetAllCategories() =>
+            Ok(await _categoryService.GetAllCategories());
     }
 }