See the C# source code
request = CreateRESTRequest("PUT", resource, requestBody, headers, "*");
...................
public HttpWebRequest CreateRESTRequest(string method, string resource, string requestBody = null, SortedList<string, string> headers = null,
string ifMatch = "", string md5 = "")
{
byte[] byteArray = null;
DateTime now = DateTime.UtcNow;
string uri = Endpoint + resource;
HttpWebRequest request = HttpWebRequest.Create(uri) as HttpWebRequest;
request.Method = method;
request.ContentLength = 0;
request.Headers.Add("x-ms-date", now.ToString("R", System.Globalization.CultureInfo.InvariantCulture));
request.Headers.Add("x-ms-version", "2009-09-19");
if (IsTableStorage)
{
request.ContentType = "application/atom+xml";
request.Headers.Add("DataServiceVersion", "1.0;NetFx");
request.Headers.Add("MaxDataServiceVersion", "1.0;NetFx");
}
if (headers != null)
{
foreach (KeyValuePair<string, string> header in headers)
{
request.Headers.Add(header.Key, header.Value);
}
}
if (!String.IsNullOrEmpty(requestBody))
{
request.Headers.Add("Accept-Charset", "UTF-8");
byteArray = Encoding.UTF8.GetBytes(requestBody);
request.ContentLength = byteArray.Length;
}
request.Headers.Add("Authorization", AuthorizationHeader(method, now, request, ifMatch, md5));
if (!String.IsNullOrEmpty(requestBody))
{
request.GetRequestStream().Write(byteArray, 0, byteArray.Length);
}
return request;
}
................................
// Generate an authorization header.
public string AuthorizationHeader(string method, DateTime now, HttpWebRequest request, string ifMatch = "", string md5 = "")
{
string MessageSignature;
if (IsTableStorage)
{
MessageSignature = String.Format("{0}\n\n{1}\n{2}\n{3}",
method,
"application/atom+xml",
now.ToString("R", System.Globalization.CultureInfo.InvariantCulture),
GetCanonicalizedResource(request.RequestUri, StorageAccount)
);
}
else
{
MessageSignature = String.Format("{0}\n\n\n{1}\n{5}\n\n\n\n{2}\n\n\n\n{3}{4}",
method,
(method == "GET" || method == "HEAD") ? String.Empty : request.ContentLength.ToString(),
ifMatch,
GetCanonicalizedHeaders(request),
GetCanonicalizedResource(request.RequestUri, StorageAccount),
md5
);
}
byte[] SignatureBytes = System.Text.Encoding.UTF8.GetBytes(MessageSignature);
System.Security.Cryptography.HMACSHA256 SHA256 = new System.Security.Cryptography.HMACSHA256(Convert.FromBase64String(StorageKey));
String AuthorizationHeader = "SharedKey " + StorageAccount + ":" + Convert.ToBase64String(SHA256.ComputeHash(SignatureBytes));
return AuthorizationHeader;
}
From those code above, the IfMatch = "*" is passed through to MessageSingaure, but the problem is here: IsTableStorage is true, the IfMatch header is not used. I think this is the real problem.
The code is got from this forum somewhere. I think it is out of date. I do not know how to fix this by adding the IfMatch to header for table storage. What is the correct format of MessageSignature for table storage? Thanks