Generate a JWT token

Token.cs

using System.IdentityModel.Tokens.Jwt;
using System.Security.Claims;
using System.Security.Principal;
using System.Text;
using Microsoft.IdentityModel.Tokens;

namespace Example
{
    class Token
    {
        public string GenerateToken(IIdentity identity)
        {
            var key = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(_configuration["API:Key"]));

            var tokenDescriptor = new SecurityTokenDescriptor
            {
                Audience = _configuration["API:Audience"],
                Issuer = _configuration["API:Issuer"],
                SigningCredentials = new SigningCredentials(key, SecurityAlgorithms.HmacSha256),
                Subject = new ClaimsIdentity(identity)
            };

            var handler = new JwtSecurityTokenHandler();
            var token = handler.CreateJwtSecurityToken(tokenDescriptor);
            var encoded = handler.WriteToken(token);

            return encoded;
        }
    }
}