c# - 调用 API : How to provide these parameters (key, 随机数和签名)

Question

我正在尝试实现一个 API。通常这很简单，但是这个给我带来了问题。 但是，我很确定问题出在我身上，而不是 API。

此特定 API 的网址:

https://www.bitstamp.net/api/

我想对“账户余额”进行 POST 调用。目前我得到以下答案:

{"error": "Missing key, signature and nonce parameters"}

我试着用下面的代码来做:

        var path = "https://www.bitstamp.net/api/user_transactions";
        var nonce = GetNonce();
        var signature = GetSignature(nonce);

        using (WebClient client = new WebClient())
        {

            byte[] response = client.UploadValues(path, new NameValueCollection()
           {
               { "key", Constants.ThirdParty.BitStamp.ApiKey },
               { "signature", signature },
               { "nonce", nonce},

           });
            var str = System.Text.Encoding.Default.GetString(response);
        }

        return 0.0m;

这是我的两个辅助函数:

    private string GetSignature(int nonce)
    {
        string msg = string.Format("{0}{1}{2}", nonce,
            Constants.ThirdParty.BitStamp.ClientId,
            Constants.ThirdParty.BitStamp.ApiKey);

        return HelperFunctions.sign(Constants.ThirdParty.BitStamp.ApiSecret, msg);
    }

    public static int GetNonce()
    {
        return (int) (DateTime.Now - new DateTime(1970, 1, 1)).TotalSeconds;
    }

我的加密签名函数是这个:

    public static String sign(String key, String stringToSign)
    {
        System.Text.ASCIIEncoding encoding = new System.Text.ASCIIEncoding();

        byte[] keyByte = encoding.GetBytes(key);
        HMACSHA256 hmacsha256 = new HMACSHA256(keyByte);

        return Convert.ToBase64String(hmacsha256.ComputeHash(encoding.GetBytes(stringToSign)));
    }

知道为什么我会收到“缺少 key ”错误吗？有什么明显的我做错了吗(可能是:))？

编辑:

Fiddler 告诉我我发布了以下数据:

key=mykeymykey&signature=PwhdkSek6GP%2br%2bdd%2bS5aU1MryXgrfOD4fLH05D7%2fRLQ%3d&nonce=1382299103%2c21055

编辑#2:

生成签名的更新代码:

private string GetSignature(int nonce)
    {
        string msg = string.Format("{0}{1}{2}", nonce,
            Constants.ThirdParty.BitStamp.ClientId,
            Constants.ThirdParty.BitStamp.ApiKey);

        return HelperFunctions.ByteArrayToString(HelperFunctions.SignHMACSHA256(
            Constants.ThirdParty.BitStamp.ApiSecret, msg)).ToUpper();
    }
public static byte[] SignHMACSHA256(String key, byte[] data)
{
    HMACSHA256 hashMaker = new HMACSHA256(Encoding.ASCII.GetBytes(key));
    return hashMaker.ComputeHash(data);
}

public static byte[] StrinToByteArray(string str)
{
    byte[] bytes = new byte[str.Length * sizeof(char)];
    System.Buffer.BlockCopy(str.ToCharArray(), 0, bytes, 0, bytes.Length);
    return bytes;
}

public static string ByteArrayToString(byte[] ba)
{
    return BitConverter.ToString(ba).Replace("-", "");
}

Answer 1

我认为问题在于您使用的是 base64 (Convert.ToBase64String)，但在 API 文档的相关部分中，它是这样写的:

Signature is a HMAC-SHA256 encoded message containing: nonce, client ID and API key. The HMAC-SHA256 code must be generated using a secret key that was generated with your API key. This code must be converted to it's hexadecimal representation (64 uppercase characters).

所以你必须将字节数组转换为十六进制字符串。看这个question获得一些如何做的例子。