promiscuity/microservices/AuthApi/Services/JwtTokenService.cs

using AuthApi.Models;
using Microsoft.IdentityModel.Tokens;
using System.IdentityModel.Tokens.Jwt;
using System.Security.Claims;
using System.Text;

namespace AuthApi.Services;

public class JwtTokenService
{
    private readonly IConfiguration _cfg;

    public JwtTokenService(IConfiguration cfg) => _cfg = cfg;

    public (string Token, string Jti, DateTime ExpiresUtc) Generate(User user)
    {
        var key = Encoding.UTF8.GetBytes(_cfg["Jwt:Key"] ?? throw new InvalidOperationException("Jwt:Key missing"));
        var issuer = _cfg["Jwt:Issuer"] ?? "GameAuthApi";
        var audience = _cfg["Jwt:Audience"] ?? issuer;
        var credentials = new SigningCredentials(new SymmetricSecurityKey(key), SecurityAlgorithms.HmacSha256);
        var jti = Guid.NewGuid().ToString("N");
        var claims = new[]
        {
            new Claim(ClaimTypes.Name, user.Username),
            new Claim(ClaimTypes.NameIdentifier, user.Id),
            new Claim(ClaimTypes.Role, user.Role),
            new Claim(JwtRegisteredClaimNames.Jti, jti)
        };
        var expiresUtc = DateTime.UtcNow.AddMinutes(15);
        var token = new JwtSecurityToken(issuer, audience, claims, expires: expiresUtc, signingCredentials: credentials);
        return (new JwtSecurityTokenHandler().WriteToken(token), jti, expiresUtc);
    }
}