private async static Task SeedTopics(int userId, ITopicRepository repository) { List <Topic> topics = new List <Topic>() { new Topic() { Name = "Others", OwnerId = null }, new Topic() { Name = "Food", OwnerId = null }, new Topic() { Name = "Transport", OwnerId = null }, new Topic() { Name = "Health", OwnerId = null }, new Topic() { Name = "Sport", OwnerId = userId } }; await repository.AddRange(topics); await repository.SaveChangesAsync(); }