I’ve been using a very simple C# function to post alerts to my community on Twitter. Has worked well over the past few years until last Friday. Now suddenly the very same code is intermittently throwing 401 errors. The behavior I’m seeing is that I run a very simple test in VisualStudio and it works fine with a test string like ‘This is a Twitter API test.’
Then I start adding a URL from tinyurl or a few more words and it suddenly triggers the 401. I made sure everything is encoded properly - please see my code which is posted below. By the way I did recreate all my tokens and even created a new app in Application Management, but to no avail. It works for one or two tests with very short updates, but as soon as I include anything of substance (e.g. a URL or a few more words) it’ll start throwing this error. Once again, I have used this code for years for literally thousands of tweets including URLs and various hashtags, etc. etc. - never failed me. All this trouble started last Friday. Has my account been flagged or something?
Any help would be appreciated as I’m pulling my hair out over this. Here’s my code:
private String PostMessageToTwitter(string message)
{
string facebookURL = "https://api.twitter.com/1.1/statuses/update.json";
//set the access tokens (REQUIRED)
string oauth_consumer_key = "xxxx";
string oauth_consumer_secret = "xxxx";
string oauth_token = "xxx-xxx";
string oauth_token_secret = "xxxxx";
// set the oauth version and signature method
string oauth_version = "1.0";
string oauth_signature_method = "HMAC-SHA1";
// create unique request details
string oauth_nonce = Convert.ToBase64String(new ASCIIEncoding().GetBytes(DateTime.Now.Ticks.ToString()));
System.TimeSpan timeSpan = (DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc));
string oauth_timestamp = Convert.ToInt64(timeSpan.TotalSeconds).ToString();
// create oauth signature
string baseFormat = "oauth_consumer_key={0}&oauth_nonce={1}&oauth_signature_method={2}" + "&oauth_timestamp={3}&oauth_token={4}&oauth_version={5}&status={6}";
string baseString = string.Format(
baseFormat,
oauth_consumer_key,
oauth_nonce,
oauth_signature_method,
oauth_timestamp, oauth_token,
oauth_version,
Uri.EscapeDataString(message)
);
string oauth_signature = null;
using (HMACSHA1 hasher = new HMACSHA1(ASCIIEncoding.ASCII.GetBytes(Uri.EscapeDataString(oauth_consumer_secret) + "&" + Uri.EscapeDataString(oauth_token_secret))))
{
oauth_signature = Convert.ToBase64String(hasher.ComputeHash(ASCIIEncoding.ASCII.GetBytes("POST&" + Uri.EscapeDataString(facebookURL) + "&" + Uri.EscapeDataString(baseString))));
}
// create the request header
string authorizationFormat = "OAuth oauth_consumer_key=\"{0}\", oauth_nonce=\"{1}\", " + "oauth_signature=\"{2}\", oauth_signature_method=\"{3}\", " + "oauth_timestamp=\"{4}\", oauth_token=\"{5}\", " + "oauth_version=\"{6}\"";
string authorizationHeader = string.Format(
authorizationFormat,
Uri.EscapeDataString(oauth_consumer_key),
Uri.EscapeDataString(oauth_nonce),
Uri.EscapeDataString(oauth_signature),
Uri.EscapeDataString(oauth_signature_method),
Uri.EscapeDataString(oauth_timestamp),
Uri.EscapeDataString(oauth_token),
Uri.EscapeDataString(oauth_version)
);
HttpWebRequest objHttpWebRequest = (HttpWebRequest)WebRequest.Create(facebookURL);
objHttpWebRequest.Headers.Add("Authorization", authorizationHeader);
objHttpWebRequest.Method = "POST";
objHttpWebRequest.ContentType = "application/x-www-form-urlencoded";
using (Stream objStream = objHttpWebRequest.GetRequestStream())
{
byte[] content = ASCIIEncoding.ASCII.GetBytes("status=" + Uri.EscapeDataString(message));
objStream.Write(content, 0, content.Length);
}
var responseResult = "";
try
{
//success posting
WebResponse objWebResponse = objHttpWebRequest.GetResponse();
StreamReader objStreamReader = new StreamReader(objWebResponse.GetResponseStream());
responseResult = objStreamReader.ReadToEnd().ToString();
}
catch (Exception ex)
{
//throw exception error
responseResult = "Twitter Post Error: " + ex.Message.ToString() + ", authHeader: " + authorizationHeader;
}
return responseResult;
}
}
