Should I seed Identity database with Roles or Claims of type Role? - asp.net-core

Question

I am writing an ASP.NET Core 1.1 web application. Now I am trying to setup my database so that it is ready for use but I am stomped at something that seems basic...
I am pretty familiar with Roles and somewhat with Claims. I know I can create a Claim of type ClaimTypes.Role. But when I am going to seed my Identity database with users, roles, etc. I am not clear on these items:
Should I just create standard Roles using RoleManager only?
Should I create a Claim of ClaimTypes.Role only?
Should I do both for the system to work?
For example, I want to have roles Admin, Owner, Employee and Plain.
Admin
identity:full
Owner
identity:medium
billing:full
Employee
identity:low
billing:view
Plain
identity:low
By the way, the roles I want to create (each having one or more permissions as claims) should be valid for use in authorization (with the Authorize attribute on the controller).

Answer 1

In my opinion - If you starting new project use Claims only.
Perhaps it's easier to understand and use the Roles using RoleManager, but Claims are more generic, flexible and powerful.
Claims are a little bit harder to start, but then they are very easy to use, especially in the custom policy-based authorization or authorization handlers (for example in a resource-based authorization).
Please read more:
Claims-Based Authorization
Custom Policy-Based Authorization
Resource Based Authorization
View Based Authorization
And small example how to create a custom policy using the Claims:
In Startup.cs
services.AddAuthorization(options =>
{
options.AddPolicy("Employee", p =>
{
p.RequireAuthenticatedUser();
p.RequireClaim(ClaimTypes.Role, "Employee");
p.Build();
});
});