Support for multiple Roles

[gkama]

Overview
Add support for multiple roles for a user in the JWT. This will include a database changes - schema, etc.

For example, the roles object in the JWT should look like this

{
  "iss": "https://www.jerriepelser.com",
  "aud": "blog-readers",
  "sub": "123456",
  "exp": 1499863217,
  "roles": [ "Admin", "SuperUser" ]
}

Use it as [Authorize(Roles = "")]

public class ValuesController : Controller
{
    [Authorize(Roles = "Admin")]
    [HttpGet("ping/admin")]
    public string PingAdmin()
    {
        return "Pong";
    }
}

Current
The User and Client entities have a RoleId reference (as a foreign key) to the Role entity. This is a one-to-one relationship

Solution
Remove the current relationship between the User, Client and Role entities. Create 2 new entities - UserRole and ClientRole. These will store a one-to-many relationship between a UserId / ClientId and RoleId

Task breakdown
When all tasks are completed, then this will reach the definition of done

• Create separate UserRole entity that stores UserId and RoleId. Foreign keys from User and Role entities
• Create separate ClientRole entity that stores ClientId and RoleId. Foreign keys from Client and Role entities
• Populate UserRole and ClientRole entities and PostgreSQL tables
• Add functionality to get the many roles stored in the entities
• Add those claims in the JWT generation and is returned to the end-user
• Feature flag?
• Remove RoleId from User entity
• Remove RoleId from Client entity
• Add / update unit tests
• Perform integration tests