private async Task <HttpRequestMessage> PreparePutRequestAsync(byte[] byteArr, string filename)
{
AwsV4SignatureCalculator calculator = new AwsV4SignatureCalculator(_secretKey, _service, _region);
HttpRequestMessage requestMessage = new HttpRequestMessage(HttpMethod.Put, new Uri($"{_protocol}://{_endpoint}/{_bucketName}/{_supPath}/{filename}"));
DateTime now = DateTime.UtcNow;
var dateTimeStamp = now.ToString(AwsV4SignatureCalculator.Iso8601DateTimeFormat, CultureInfo.InvariantCulture);
var dateStamp = now.ToString(AwsV4SignatureCalculator.Iso8601DateFormat, CultureInfo.InvariantCulture);
ByteArrayContent content = new ByteArrayContent(byteArr);
requestMessage.Content = content;
var hash = await AwsV4SignatureCalculator.GetPayloadHashAsync(requestMessage);
string[] headers = AddStandardHeadersToRequest(requestMessage, dateTimeStamp, hash);
string signature = await calculator.CalculateSignatureAsync(requestMessage, headers, now);
string authHeader = GetAuthHeader(dateStamp, headers, signature);
requestMessage.Headers.TryAddWithoutValidation("Authorization", authHeader);
return(requestMessage);
}
/// <summary>
/// Returns presigned URL with defined expire time
/// </summary>
/// <param name="v"></param>
/// <returns></returns>
public string GetPresignedUrl(string filename, TimeSpan expirationTime = default)
{
if (expirationTime == default)
{
expirationTime = TimeSpan.FromHours(_presignedUrlExpirationInHours);
}
var formatedPath = FormatePath(filename);
var expiresOn = DateTime.UtcNow + expirationTime;
var period = Convert.ToInt64((expiresOn.ToUniversalTime() - DateTime.UtcNow).TotalSeconds);
var requestDateTime = DateTime.UtcNow;
var dateTimeStamp = requestDateTime.ToString(AwsV4SignatureCalculator.Iso8601DateTimeFormat, CultureInfo.InvariantCulture);
var requestDateTimeStamp = requestDateTime.ToString(AwsV4SignatureCalculator.Iso8601DateFormat, CultureInfo.InvariantCulture);
var queryParams = new StringBuilder();
queryParams.AppendFormat("{0}={1}", AwsV4SignatureCalculator.X_Amz_Algorithm, UrlHelper.UrlEncode("AWS4-HMAC-SHA256"));
queryParams.AppendFormat(
"&{0}={1}",
AwsV4SignatureCalculator.X_Amz_Credential,
UrlHelper.UrlEncode($"{_accessKey}/{requestDateTimeStamp}/{_region}/{_service}/aws4_request"));
queryParams.AppendFormat("&{0}={1}", AwsV4SignatureCalculator.X_Amz_Date, UrlHelper.UrlEncode(dateTimeStamp));
queryParams.AppendFormat("&{0}={1}", AwsV4SignatureCalculator.X_Amz_Expires, UrlHelper.UrlEncode(period.ToString()));
queryParams.AppendFormat("&{0}={1}", AwsV4SignatureCalculator.X_Amz_SignedHeaders, UrlHelper.UrlEncode("host"));
var endpointUri = new UriBuilder($"{_protocol}://{_endpoint}/{_bucketName}/{_supPath}/{formatedPath}")
{
Query = queryParams.ToString()
};
HttpRequestMessage requestMessage = new HttpRequestMessage(HttpMethod.Get, endpointUri.Uri);
requestMessage.Headers.Add("Host", _endpoint);
string[] headers = { "host" };
AwsV4SignatureCalculator calculator = new AwsV4SignatureCalculator(_secretKey, _service, _region);
string signature = calculator.CalculateSignatureAsync(requestMessage, headers, requestDateTime, true).Result;
// remove unnecessary port
endpointUri.Port = -1;
var urlStringBuilder = new StringBuilder(endpointUri.ToString());
urlStringBuilder.AppendFormat("&{0}={1}", AwsV4SignatureCalculator.X_Amz_Signature, UrlHelper.UrlEncode(signature));
var presignedUrl = urlStringBuilder.ToString();
return(presignedUrl);
}
