.net core identity集成微信授权登录

最快的方式是直接nuget安装AspNetCore.Authentication.WeChat包。

想要知道是如何实现的，可以看下面github上面的源码。

源码在这里：https://github.com/china-live/QQConnect

使用方式：

1. 安装nuget的包以后，在startup.cs中添加微信授权认证并配置appId和AppSecret，使用缓存保存State数据（微信State Too Long 报错 由于微信的设置，state最多128字节，但是默认生成的state会超出限制，所以需要加入缓存）

   iservices.AddAuthentication().AddWeChat(options =>
               {
                   options.AppId = Configuration["WeixinSetting:WeixinAppId"];
                   options.AppSecret = Configuration["WeixinSetting:WeixinAppSecret"];
                   options.UseCachedStateDataFormat = true;
               });

2. 新建一个Controller，编写action

           /// <summary>
           /// 微信授权登录
           /// </summary>
           /// <param name="returnUrl">用户尝试进入的需要登录的页面</param>
           /// <returns></returns>
           [AllowAnonymous]
           public ActionResult WxLogin(string returnUrl)
           {
   
               string redirectUrl = Url.Action("BaseCallback",
                   new { ReturnUrl = returnUrl });
   
               var properties = signInManager
                   .ConfigureExternalAuthenticationProperties("WeChat", redirectUrl);
               return new ChallengeResult("WeChat", properties);
           }
   
           /// <summary>
           /// 回调
           /// </summary>
           /// <param name="provider"></param>
           /// <param name="returnUrl">用户最初尝试进入的页面</param>
           /// <returns></returns>
           [AllowAnonymous]
           public async Task<IActionResult> BaseCallback(string provider = null, string returnUrl = "/")
           {
               try
               {
                   ExternalLoginInfo info = await signInManager.GetExternalLoginInfoAsync();
                   if (info == null)
                   {
                       return RedirectToAction(nameof(Login));
                   }
                   var result = await signInManager.ExternalLoginSignInAsync(
                       info.LoginProvider, info.ProviderKey, false);
                   if (result.Succeeded)
                   {
                       return Redirect(returnUrl);
                   }
                   else
                   {
                       Account user = new Account
                       {
                           OpenId = info.Principal.FindFirst(ClaimTypes.NameIdentifier).Value,
                           UserName =
                               info.Principal.FindFirst(ClaimTypes.NameIdentifier).Value
                       };
                       IdentityResult identResult = await userManager.CreateAsync(user);
                       if (identResult.Succeeded)
                       {
                           identResult = await userManager.AddLoginAsync(user, info);
                           if (identResult.Succeeded)
                           {
                               await signInManager.SignInAsync(user, false);
                               return Redirect(returnUrl);
                           }
                       }
                       return AccessDenied();
                   }
               }
               catch (Exception ex)
               {
                   return Content("发生错误：" + ex);
               }
           }