【阿里云】通过OpenAPI获取Token（C#）

使用 C# 实现 https://help.aliyun.com/zh/isi/getting-started/use-http-or-https-to-obtain-an-access-token

public static class TokenHelper
{
    public static async Task<string> GetAccessTokenAsync(string accessKeyId, string accessKeySecret)
    {
        var queryParamsMap = new Dictionary<string, string>();

        queryParamsMap.Add("AccessKeyId", accessKeyId);
        queryParamsMap.Add("Action", "CreateToken");
        queryParamsMap.Add("Version", "2019-02-28");
        queryParamsMap.Add("Timestamp", GetISO8601Time());
        queryParamsMap.Add("Format", "JSON");
        queryParamsMap.Add("RegionId", "cn-shanghai");
        queryParamsMap.Add("SignatureMethod", "HMAC-SHA1");
        queryParamsMap.Add("SignatureVersion", "1.0");
        queryParamsMap.Add("SignatureNonce", GetUniqueNonce());

        string queryString = CanonicalizedQuery(queryParamsMap);

        string method = "GET";
        string urlPath = "/";
        string stringToSign = CreateStringToSign(method, urlPath, queryString);

        string signature = Sign(stringToSign, accessKeySecret + "&");

        string queryStringWithSign = "Signature=" + signature + "&" + queryString;

        var url = "http://nls-meta.cn-shanghai.aliyuncs.com/?" + queryStringWithSign;

        var client = new HttpClient();
        var response = await client.GetAsync(url);
        var json = await response.Content.ReadAsStringAsync();
        response.Dispose();
        client.Dispose();

        return json;
    }

    private static string GetISO8601Time()
    {
        return DateTimeOffset.UtcNow.ToString("yyyy-MM-ddTHH:mm:ssZ");
    }

    private static string GetUniqueNonce()
    {
        return Guid.NewGuid().ToString();
    }

    private static string PercentEncode(string value)
    {
        return Uri.EscapeDataString(value);
    }

    private static string CanonicalizedQuery(Dictionary<string, string> queryParamsMap)
    {
        var sortedKeys = queryParamsMap.Keys.Order();
        var canonicalizedQueryString = new StringBuilder();
        foreach (var key in sortedKeys)
        {
            canonicalizedQueryString
                .Append('&')
                .Append(PercentEncode(key))
                .Append('=')
                .Append(PercentEncode(queryParamsMap[key]));
        }
        return canonicalizedQueryString.ToString().Substring(1);
    }

    private static string CreateStringToSign(string method, string urlPath, string queryString)
    {
        var strBuilderSign = new StringBuilder();
        strBuilderSign.Append(method);
        strBuilderSign.Append('&');
        strBuilderSign.Append(PercentEncode(urlPath));
        strBuilderSign.Append('&');
        strBuilderSign.Append(PercentEncode(queryString));
        return strBuilderSign.ToString();
    }

    private static string Sign(string stringToSign, string accessKeySecret)
    {
        var key = Encoding.UTF8.GetBytes(accessKeySecret);
        var source = Encoding.UTF8.GetBytes(stringToSign);
        var signData = HMACSHA1.HashData(key, source);
        var signBase64 = Convert.ToBase64String(signData);
        var signUrlEncode = PercentEncode(signBase64);
        return signUrlEncode;
    }
}