ProfileService.cs

using System.Linq;
using System.Security.Claims;
using IdentityModel;
using IdentityServer4.Models;
using IdentityServer4.Services;
using System.Threading.Tasks;
using BlazorTemplate.Server.Models;
using IdentityServer4.Extensions;
using Microsoft.AspNetCore.Identity;

namespace BlazorTemplate.Server
{
    public class ProfileService : IProfileService
    {
        private readonly IUserClaimsPrincipalFactory<ApplicationUser> _claimsFactory;
        private readonly UserManager<ApplicationUser> _userManager;

        public ProfileService(UserManager<ApplicationUser> userManager, IUserClaimsPrincipalFactory<ApplicationUser> claimsFactory)
        {
            _userManager = userManager;
            _claimsFactory = claimsFactory;
        }

        public async Task GetProfileDataAsync(ProfileDataRequestContext context)
        {
            var sub = context.Subject.GetSubjectId();
            var user = await _userManager.FindByIdAsync(sub);
            var principal = await _claimsFactory.CreateAsync(user);
            var claims = principal.Claims.ToList();
            
            var nameClaim = context.Subject.FindAll(JwtClaimTypes.Name);
            
            var roles = await _userManager.GetRolesAsync(user);
            var roleClaims = roles.Select(role => new Claim(JwtClaimTypes.Role, role));
            
            claims = claims.Where(claim => context.RequestedClaimTypes.Contains(claim.Type)).ToList();

            // Add custom claims in token here based on user properties or any other source
            claims.Add(new Claim("username", user.UserName ?? string.Empty));
            claims.AddRange(nameClaim);
            claims.AddRange(roleClaims); 
            context.IssuedClaims = claims;
        }

        public async Task IsActiveAsync(IsActiveContext context)
        {
            var sub = context.Subject.GetSubjectId();
            var user = await _userManager.FindByIdAsync(sub);
            context.IsActive = user != null;
        }
    }
}