ABP Vnext IdentityServer4扩展微信小程序授权登录

abp vnext IdentityServer4 使用IExtensionGrantValidator接口进行的授权登入扩展，按照以下代码可实现，欢迎交流指正。
微信返回数据字段类- Code2Session 类

public class Code2Session
{
  /// 

  /// 用户唯一标识
  /// 
  public string openid { get; set; }
  /// 

  /// 会话密钥
  /// 
  public string session_key { get; set; }
  /// 

  /// 用户在开放平台的唯一标识符，若当前小程序已绑定到微信开放平台帐号下会返回
  /// 
  public string unionid { get; set; }
  /// 

  /// 错误码
  /// 
  public int errcode { get; set; }
  /// 

  /// 错误信息
  /// 
  public string  errmsg { get; set; } 
}

在HttpApi.Host新建类

using IdentityServer4.Validation;
using Microsoft.AspNetCore.Identity;
using System;
using System.Collections.Generic;
using System.Security.Claims;
using System.Threading.Tasks;
using Volo.Abp.Identity;
using Volo.Abp.Json;
using System.Net.Http;

namespace Demo
{
    public class ExtensionGrantTypes
    {
        //扩展授权名称
        public const string WeChatGrantType = "wechat_code";
    }

    public class WeChatGrantValidator : IExtensionGrantValidator
    {
        public string GrantType => ExtensionGrantTypes.WeChatGrantType;

        private readonly UserManager<Volo.Abp.Identity.IdentityUser> _userManager;
        private readonly IJsonSerializer _jsonSerializer;

        public WeChatGrantValidator(
            UserManager<Volo.Abp.Identity.IdentityUser> userLoginManager,
            IJsonSerializer jsonSerializer)
        { 
            _userManager = userLoginManager;
            _jsonSerializer = jsonSerializer;
        }
        public async Task ValidateAsync(ExtensionGrantValidationContext context)
        {
            string code = context.Request.Raw.Get("Code");
            if (string.IsNullOrEmpty(code)) 
            { 
                context.Result = new GrantValidationResult(IdentityServer4.Models.TokenRequestErrors.InvalidGrant);
            }
            //微信开发平台验证
            string _appid = "自己的appid";
            string _secret = "自己的secret";

            string url = string.Format(
                "https://api.weixin.qq.com/sns/jscode2session?appid={0}&secret={1}&js_code={2}&grant_type=authorization_code",
                _appid,
                _secret,
                code);
            HttpClient client = new HttpClient();
            HttpResponseMessage response = client.GetAsync(url).Result;
            if (response.IsSuccessStatusCode)
            {
                string resContent = response.Content.ReadAsStringAsync().Result;
                var code2session  = _jsonSerializer.Deserialize<Code2Session>(resContent);
                switch (code2session.errcode)
	            {
	                case 0:
	                    string providerKey = code2session.openid;
	                    context.Result = await ServerValidate("WeChat", providerKey);
	                    break;
	                default:context.Result = new GrantValidationResult(
	                    IdentityServer4.Models.TokenRequestErrors.InvalidGrant,
	                    "wechat:"+code2session.errmsg);
	                    break;
	            } 
            }
            else
                context.Result = new GrantValidationResult(IdentityServer4.Models.TokenRequestErrors.InvalidGrant);
                
                       
        }
        readonly DateTime DateTime1970 = new DateTime(1970, 1, 1).ToLocalTime();
        /// 

        /// 服务器验证并输出用户信息，以便自动生成token
        /// 
        /// 
        /// 
        /// 
        private async Task<GrantValidationResult> ServerValidate(string loginProvider,string providerKey)
        {
            var user = await _userManager.FindByLoginAsync(loginProvider, providerKey);
            if (user == null)
                return new GrantValidationResult(IdentityServer4.Models.TokenRequestErrors.InvalidGrant);

            var principal = new ClaimsPrincipal();
            List<ClaimsIdentity> claimsIdentity = new List<ClaimsIdentity>();
            ClaimsIdentity identity = new ClaimsIdentity();
            identity.AddClaim(new Claim("sub", user.Id.ToString()));
            identity.AddClaim(new Claim("tenantid", user.TenantId.ToString()));
            identity.AddClaim(new Claim("idp", "local"));
            identity.AddClaim(new Claim("amr", loginProvider));

            long authTime = (long)(DateTime.Now.ToLocalTime() - DateTime1970).TotalSeconds;
            identity.AddClaim(new Claim("auth_time", authTime.ToString()));

            claimsIdentity.Add(identity);
            principal.AddIdentities(claimsIdentity);

            return new GrantValidationResult(principal);
        }
    }
}

在HttpApiHostModule.cs 文件中添加注册

public override void PreConfigureServices(ServiceConfigurationContext context)
{
    context.Services.PreConfigure<IIdentityServerBuilder>(
        builder =>
        {
            builder.AddExtensionGrantValidator<WeChatGrantValidator>();
        });
}

在Domain项目中的identityServer 文件夹中的种子数据添加grantTypes（CreateClientAsync（）下）

grantTypes: new[] { "password", "client_credentials", "authorization_code", "wechat_code" },

请求地址和参数

host:/connect/token
methon:POST
media type:aplication/x-www-form-urlencoded
body:
	grant_type=wechat_code
	code=微信小程序提供的code
	client_id=自己项目的client_id
	scope=自己项目 openid offline_access

钉钉可参考本文进行IdentityServer4扩展授权登录，欢迎交流指正,谢谢阅读。