reorganization of database layer

UserService.DatabaseLayer/Repository/IRepository.cs

@@ -0,0 +1,38 @@
+using System;
+using System.Collections.Generic;
+using System.Linq.Expressions;
+using System.Threading;
+using System.Threading.Tasks;
+using UserService.DatabaseLayer.DataModels;
+
+namespace UserService.DatabaseLayer.Repository
+{
+    public interface IRepository<T> where T : Node
+    {
+        Task<IReadOnlyList<T>> GetAllAsync(CancellationToken token = default);
+        Task<T?> GetAsync(Expression<Func<T, bool>> predicate, CancellationToken token = default);
+        Task AddAsync(T entity, CancellationToken token = default);
+        Task UpdateAsync(T entity, CancellationToken token = default);
+        Task DeleteAsync(T entity, CancellationToken token = default);
+    }
+
+    public interface IOrganizationUnitsRepository : IRepository<OrganizationUnit>
+    {
+
+    }
+
+    public interface ISecurityGroupsRepository : IRepository<SecurityGroup>
+    {
+
+    }
+
+    public interface IUsersRepository : IRepository<User>
+    {
+
+    }
+
+    public interface INodesRepository : IRepository<Node>
+    {
+
+    }
+}