public static async Task<BasicResult> DeleteScoreAsync(string serviceUrl, string consumerKey, string consumerSecret, string lisResultSourcedId)
{
var imsxEnvelope = new imsx_POXEnvelopeType
{
imsx_POXHeader = new imsx_POXHeaderType {Item = new imsx_RequestHeaderInfoType()},
imsx_POXBody = new imsx_POXBodyType {Item = new deleteResultRequest()}
};
var imsxHeader = (imsx_RequestHeaderInfoType) imsxEnvelope.imsx_POXHeader.Item;
imsxHeader.imsx_version = imsx_GWSVersionValueType.V10;
imsxHeader.imsx_messageIdentifier = Guid.NewGuid().ToString();
var imsxBody = (deleteResultRequest) imsxEnvelope.imsx_POXBody.Item;
imsxBody.resultRecord = new ResultRecordType
{
sourcedGUID = new SourcedGUIDType {sourcedId = lisResultSourcedId}
};
try
{
var webRequest = CreateLtiOutcomesRequest(
imsxEnvelope,
serviceUrl,
consumerKey,
consumerSecret);
var webResponse = await webRequest.GetResponseAsync();
return ParseDeleteResultResponse(webResponse);
}
catch (Exception ex)
{
return new BasicResult(false, ex.ToString());
}
}
public static async Task <BasicResult> PostScoreAsync(string serviceUrl, string consumerKey, string consumerSecret, string lisResultSourcedId, double?score)
{
var imsxEnvelope = new imsx_POXEnvelopeType
{
imsx_POXHeader = new imsx_POXHeaderType {
Item = new imsx_RequestHeaderInfoType()
},
imsx_POXBody = new imsx_POXBodyType {
Item = new replaceResultRequest()
}
};
var imsxHeader = (imsx_RequestHeaderInfoType)imsxEnvelope.imsx_POXHeader.Item;
imsxHeader.imsx_version = imsx_GWSVersionValueType.V10;
imsxHeader.imsx_messageIdentifier = Guid.NewGuid().ToString();
var imsxBody = (replaceResultRequest)imsxEnvelope.imsx_POXBody.Item;
imsxBody.resultRecord = new ResultRecordType
{
sourcedGUID = new SourcedGUIDType {
sourcedId = lisResultSourcedId
},
result = new ResultType
{
resultScore = new TextType
{
language = LtiConstants.ScoreLanguage,
textString = score?.ToString(new CultureInfo(LtiConstants.ScoreLanguage))
}
}
};
// The LTI 1.1 specification states in 6.1.1. that the score in replaceResult should
// always be formatted using “en” formatting
// (http://www.imsglobal.org/LTI/v1p1p1/ltiIMGv1p1p1.html#_Toc330273034).
try
{
var webRequest = CreateLtiOutcomesRequest(
imsxEnvelope,
serviceUrl,
consumerKey,
consumerSecret);
using (var webResponse = await webRequest.GetResponseAsync())
{
return(ParsePostResultResponse(webResponse));
}
}
catch (Exception ex)
{
return(new BasicResult(false, ex.ToString()));
}
}
private static HttpWebRequest CreateLtiOutcomesRequest(imsx_POXEnvelopeType imsxEnvelope, string url, string consumerKey, string consumerSecret)
{
var webRequest = (HttpWebRequest)WebRequest.Create(url);
webRequest.Method = "POST";
webRequest.ContentType = "application/xml";
var parameters = new NameValueCollection();
parameters.AddParameter(OAuthConstants.ConsumerKeyParameter, consumerKey);
parameters.AddParameter(OAuthConstants.NonceParameter, Guid.NewGuid().ToString());
parameters.AddParameter(OAuthConstants.SignatureMethodParameter, OAuthConstants.SignatureMethodHmacSha1);
parameters.AddParameter(OAuthConstants.VersionParameter, OAuthConstants.Version10);
// Calculate the timestamp
var ts = DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0, 0);
var timestamp = Convert.ToInt64(ts.TotalSeconds);
parameters.AddParameter(OAuthConstants.TimestampParameter, timestamp);
// Calculate the body hash
using (var ms = new MemoryStream())
using (var sha1 = new SHA1CryptoServiceProvider())
{
ImsxRequestSerializer.Serialize(ms, imsxEnvelope);
ms.Position = 0;
ms.CopyTo(webRequest.GetRequestStream());
var hash = sha1.ComputeHash(ms.ToArray());
var hash64 = Convert.ToBase64String(hash);
parameters.AddParameter(OAuthConstants.BodyHashParameter, hash64);
}
// Calculate the signature
var signature = OAuthUtility.GenerateSignature(webRequest.Method, webRequest.RequestUri, parameters,
consumerSecret);
parameters.AddParameter(OAuthConstants.SignatureParameter, signature);
// Build the Authorization header
var authorization = new StringBuilder(OAuthConstants.AuthScheme).Append(" ");
foreach (var key in parameters.AllKeys)
{
authorization.AppendFormat("{0}=\"{1}\",", key, WebUtility.UrlEncode(parameters[key]));
}
webRequest.Headers["Authorization"] = authorization.ToString(0, authorization.Length - 1);
return(webRequest);
}
public static LisResult ReadScore(string serviceUrl, string consumerKey, string consumerSecret, string lisResultSourcedId)
{
var imsxEnvelope = new imsx_POXEnvelopeType
{
imsx_POXHeader = new imsx_POXHeaderType {
Item = new imsx_RequestHeaderInfoType()
},
imsx_POXBody = new imsx_POXBodyType {
Item = new readResultRequest()
}
};
var imsxHeader = (imsx_RequestHeaderInfoType)imsxEnvelope.imsx_POXHeader.Item;
imsxHeader.imsx_version = imsx_GWSVersionValueType.V10;
imsxHeader.imsx_messageIdentifier = Guid.NewGuid().ToString();
var imsxBody = (readResultRequest)imsxEnvelope.imsx_POXBody.Item;
imsxBody.resultRecord = new ResultRecordType
{
sourcedGUID = new SourcedGUIDType {
sourcedId = lisResultSourcedId
}
};
try
{
var webRequest = CreateLtiOutcomesRequest(
imsxEnvelope,
serviceUrl,
consumerKey,
consumerSecret);
var webResponse = webRequest.GetResponse() as HttpWebResponse;
return(ParseReadResultResponse(webResponse));
}
catch (Exception ex)
{
return(new LisResult {
IsValid = false, Message = ex.ToString()
});
}
}
