JwtHelper.cs

using System;
using System.Collections.Generic;
using System.IdentityModel.Tokens.Jwt;
using System.Linq;
using System.Security.Claims;
using System.Text;
using System.Threading.Tasks;
using Core.WebApi.Library;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Options;
using Microsoft.IdentityModel.Tokens;
using JwtRegisteredClaimNames = Microsoft.IdentityModel.JsonWebTokens.JwtRegisteredClaimNames;

namespace Core3.xWebApi
{
    public class JwtHelper
    {
        public JwtHelper()
        {
        }

        public static string IssueJWT(TokenModelJWT tokenModel)
        {
            var dateTime = DateTime.UtcNow;
            string iss = ConfigManager.Configuration.GetSection("Audience:Issuer").Value;
            string aud = ConfigManager.Configuration.GetSection("Audience:Audience").Value;
            string secret = ConfigManager.Configuration.GetSection("Audience:Secret").Value;

            var claims = new List<Claim>()
            {
                //下边为Claim的默认配置
                new Claim(JwtRegisteredClaimNames.Jti, tokenModel.Uid.ToString()),
                new Claim(JwtRegisteredClaimNames.Iat, $"{new DateTimeOffset(DateTime.Now).ToUnixTimeSeconds()}"),
                new Claim(JwtRegisteredClaimNames.Nbf,$"{new DateTimeOffset(DateTime.Now).ToUnixTimeSeconds()}") ,
                //这个就是过期时间，目前是过期100秒，可自定义，注意JWT有自己的缓冲过期时间
                new Claim (JwtRegisteredClaimNames.Exp,$"{new DateTimeOffset(DateTime.Now.AddSeconds(100)).ToUnixTimeSeconds()}"),
                new Claim(JwtRegisteredClaimNames.Iss,iss),
                new Claim(JwtRegisteredClaimNames.Aud,aud),

                //new Claim(ClaimTypes.Role,tokenModel.Role),//为了解决一个用户多个角色(比如：Admin,System)，用下边的方法
            };
            claims.AddRange(tokenModel.Role.Split(',').Select(s => new Claim(ClaimTypes.Role, s)));
            //秘钥 (SymmetricSecurityKey 对安全性的要求，密钥的长度太短会报出异常)
            var key = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(secret));
            var creds = new SigningCredentials(key, SecurityAlgorithms.HmacSha256);
            var jwt = new JwtSecurityToken(
                issuer: iss,
                claims: claims,
                audience: aud,
                expires: DateTime.Now.AddMinutes(10),
                signingCredentials: creds);

            var jwtHandler = new JwtSecurityTokenHandler();
            var encodedJwt = jwtHandler.WriteToken(jwt);

            return encodedJwt;
        }
    }
}