C# PostAsync to/Token返回内部服务器错误

我有一个web Api，其中包含到启动中登录令牌设置的路由。身份验证如下：

        PublicClientId = "self";
        OAuthOptions = new OAuthAuthorizationServerOptions
        {
            TokenEndpointPath = new PathString("/Token"),
            Provider = new ApplicationOAuthProvider(PublicClientId),
            AuthorizeEndpointPath = new PathString("/api/Account/ExternalLogin"),
            AccessTokenExpireTimeSpan = TimeSpan.FromDays(1),
            AllowInsecureHttp = false
        };

将我的api登录请求路由到此处：

    [OverrideAuthentication]
    [HostAuthentication(DefaultAuthenticationTypes.ExternalCookie)]
    [AllowAnonymous]
    [Route("ExternalLogin", Name = "ExternalLogin")]
    public async Task<IHttpActionResult> GetExternalLogin(string provider, string error = null)
    {
     Authorize stuff...
    }

使用登录内容：

        var values = new Dictionary<string, string>();
        values.Add("grant_type", "password");
        values.Add("username", "usernamehere");
        values.Add("password", "passwordhere");
        var loginContent = new FormUrlEncodedContent(values); 

我收到一个（400）错误的请求。不知道下一步该做什么

我必须让令牌身份验证工作。。。没有安全性，无法发布。；）

更新：

我应该补充一点，我正在使用自定义UserStore作为标识

更新2:客户端

    public static HttpClient GetClient()
    {

        HttpClient Client = new HttpClient();

        Client.BaseAddress = new Uri(Ics2Constants.ICS2APIBaseAddress);
        Client.DefaultRequestHeaders.Accept.Clear();
        Client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

        return Client;
    }

然后使用：

using (var client = ICS2HttpClient.GetClient())
        {
            //TESTING:
            await ICS2HttpClient.Authenticate(client);

            //... more stuff after authentication 
        }   

---

身份验证包含PostAsync

Authorize属性不应置于获取令牌的任何方法之上，它应该是匿名的，以防其他人犯与我相同的愚蠢错误：

GrantResourceOwnerCredentials是验证用户/密码并分发访问令牌时/令牌路由到的位置

在我的例子中，下面的代码位于ApplicationAuthProvider.cs的Providers目录中

public class ApplicationOAuthProvider : OAuthAuthorizationServerProvider
{
    private readonly string _publicClientId;

    public ApplicationOAuthProvider(string publicClientId)
    {
        if (publicClientId == null)
        {
            throw new ArgumentNullException("publicClientId");
        }

        _publicClientId = publicClientId;
    }

    public override async Task GrantResourceOwnerCredentials(OAuthGrantResourceOwnerCredentialsContext context)
    {
       // use the userManager to find the user, check credentials, grab roles, etc.  
    }

如果有人需要更多帮助，我可以发布更多细节。我知道解决所有细节对我来说是一件痛苦的事

---

再来一张。我在mySQL Identity stuff的基础上编写了定制的Identity stuff

你能在实例化客户端的地方添加代码吗？我觉得自己很笨。我应该在GrantResourceOwnerCredentials中查找令牌请求。我有一些逻辑，需要根据我的自定义身份进行更新。。。旧逻辑失败并返回内部服务器错误。。。在外面找不到合适的地方。

using (var client = ICS2HttpClient.GetClient())
        {
            //TESTING:
            await ICS2HttpClient.Authenticate(client);

            //... more stuff after authentication 
        }   

public class ApplicationOAuthProvider : OAuthAuthorizationServerProvider
{
    private readonly string _publicClientId;

    public ApplicationOAuthProvider(string publicClientId)
    {
        if (publicClientId == null)
        {
            throw new ArgumentNullException("publicClientId");
        }

        _publicClientId = publicClientId;
    }

    public override async Task GrantResourceOwnerCredentials(OAuthGrantResourceOwnerCredentialsContext context)
    {
       // use the userManager to find the user, check credentials, grab roles, etc.  
    }