DigitalData.Core/DigitalData.Core.Security/JwtSignatureHandler.cs

using AutoMapper;
using DigitalData.Core.Abstractions.Security;
using DigitalData.Core.Security.Config;
using Microsoft.Extensions.Options;
using Microsoft.IdentityModel.Tokens;
using System.IdentityModel.Tokens.Jwt;

namespace DigitalData.Core.Security
{
    public class JwtSignatureHandler<TPrincipal> : JwtSecurityTokenHandler, IJwtSignatureHandler<TPrincipal>
    {
        private readonly ClaimDescriptor<TPrincipal> _claimDescriptor;

        private readonly IMapper _mapper;

        private readonly ICryptoFactory _cryptoFactory;

        public JwtSignatureHandler(IOptions<ClaimDescriptor<TPrincipal>> claimDescriptorOptions, IMapper mapper, ICryptoFactory cryptoFactory)
        {
            _claimDescriptor = claimDescriptorOptions.Value;
            _mapper = mapper;
            _cryptoFactory = cryptoFactory;
        }

        public SecurityToken CreateToken(TPrincipal subject, IAsymmetricTokenDescriptor descriptor)
        {
            var sDescriptor = _mapper.Map(descriptor);
            sDescriptor.Claims = _claimDescriptor.CreateClaims?.Invoke(subject);
            sDescriptor.Subject = _claimDescriptor.CreateSubject?.Invoke(subject);
            return CreateToken(sDescriptor);
        }

        public SecurityToken CreateToken(TPrincipal subject, string issuer, string audience)
        {
            var descriptor = _cryptoFactory.TokenDescriptors.Get(issuer: issuer, audience: audience)
                ?? throw new InvalidOperationException($"No or multiple token description found for issuer '{issuer}' and audience '{audience}'.");
            return CreateToken(subject: subject, descriptor: descriptor);
        }

        public SecurityToken CreateToken(TPrincipal subject, string apiRoute)
        {
            var desc = _cryptoFactory.TokenDescriptors.SingleOrDefault(desc => desc.ApiRoute == apiRoute)
                ?? throw new InvalidOperationException($"No or multiple token description found for api route '{apiRoute}'.");

            return CreateToken(subject: subject, descriptor: desc);
        }

        public string WriteToken(SecurityTokenDescriptor descriptor) => WriteToken(CreateToken(descriptor));

        public string WriteToken(TPrincipal subject, IAsymmetricTokenDescriptor descriptor)
            => WriteToken(CreateToken(subject: subject, descriptor: descriptor));

        public string WriteToken(TPrincipal subject, string issuer, string audience)
            => WriteToken(CreateToken(subject: subject, issuer: issuer, audience: audience));

        public string WriteToken(TPrincipal subject, string apiRoute) => WriteToken(CreateToken(subject: subject, apiRoute: apiRoute));
    }
}