/// <summary>
/// Writes the file from a byte array directly to the response. The output stream
/// extension must be set prior to calling this method.
/// If the response is provided and the path extension is not
/// in the list of files to use IIS compatibility mode, this is much faster than
/// copying the file contents to the output stream and should be used whenever possible.
/// If there is no response object, the method reverts to copying the file between streams.
/// </summary>
/// <param name="fileBytes">The file to render.</param>
internal void WriteFileToResponse(byte[] fileBytes)
{
using (Disposer disposer = new Disposer())
{
// Open a stream on the file. For some odd reason fxcop does not acknowledge the ability of disposer
// to actually dispose fileStream, so we give it its own using block.
using (Stream fileStream = new MemoryStream(fileBytes))
{
// If the response was provided (which it will be, in most non-test cases), then
// do the TransmitFile or WriteFile. Otherwise, copy the streams to the response output stream.
if (Response != null)
{
// IisCompatibilityMode is not considered here, because in no case do we have a file
// path that can be read by TransmitFile.
WriteIisCompatibilityModeToResponse(fileStream);
}
else
{
DetachableStream outputDS = new DetachableStream(OutputStream);
disposer.Push(outputDS);
Utilities.CopyStream(fileStream, ImpersonationBehavior.UseImpersonatedIdentity, outputDS, ImpersonationBehavior.UseImpersonatedIdentity);
outputDS.Detach();
}
}
}
}
/// <summary>
/// Writes the file from the package directly to the response and set the appropriate
/// content type in the response. If the response is provided and the path extension is not
/// in the list of files to use IIS compatibility mode, this is much faster than
/// copying the file contents to the output stream and should be used whenever possible.
/// If there is no response object, the method reverts to copying the file between streams.
/// </summary>
/// <param name="relativePath">The package-relative path to the file to render.</param>
internal void WriteFileToResponse(string relativePath)
{
// Set the mime type on the response
string pathExtension = Path.GetExtension(relativePath);
SetOutputStreamExtension(pathExtension);
using (Disposer disposer = new Disposer())
{
PackageReader pkgReader = m_session.GetPackageReader();
disposer.Push(pkgReader);
// If the response was provided (which it will be, in most non-test cases), then
// do the TransmitFile or WriteFile. Otherwise, copy the streams to the response output stream.
if (Response != null)
{
// If we are to use Compatibility mode, then write the file
if (UseCompatibilityMode(pathExtension))
{
Stream packageFile = pkgReader.GetFileStream(relativePath);
WriteIisCompatibilityModeToResponse(packageFile);
}
#if DOTNET40
else if (FileIsHtml(pathExtension))
{
SendHtmlChangingCssHref(pkgReader.GetFileStream(relativePath));
}
else if (FileIsJavascript(pathExtension))
{
SendJavascriptChangingCssHref(pkgReader.GetFileStream(relativePath));
}
#endif
else
{
pkgReader.TransmitFile(relativePath, m_context.Response);
}
}
else
{
DetachableStream outputDS = new DetachableStream(OutputStream);
disposer.Push(outputDS);
Stream packageFile = pkgReader.GetFileStream(relativePath);
disposer.Push(packageFile);
Utilities.CopyStream(packageFile, ImpersonationBehavior.UseImpersonatedIdentity, outputDS, ImpersonationBehavior.UseImpersonatedIdentity);
outputDS.Detach();
}
}
}
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2000:DisposeObjectsBeforeLosingScope")] // the writer is disposed for all code paths
internal static void CopyStream(Stream fromStream, ImpersonationBehavior readImpersonationBehavior, Stream toStream, ImpersonationBehavior writeImpersonationBehavior)
{
using (Disposer disposer = new Disposer())
{
DetachableStream dsToStream = new DetachableStream(toStream);
disposer.Push(dsToStream);
BinaryWriter writer = new BinaryWriter(dsToStream);
disposer.Push(writer);
// An addition revert during write operations is required if the setting for reading and writing
// is not the same
bool requiresWriteRevert = (readImpersonationBehavior != writeImpersonationBehavior);
using (ImpersonateIdentity readId = new ImpersonateIdentity(readImpersonationBehavior))
{
byte[] bytesIn = new byte[65536];
int bytesRead;
while ((bytesRead = fromStream.Read(bytesIn, 0, bytesIn.Length)) != 0)
{
// If we have to impersonate to write, then do it. Otherwise skip it.
if (requiresWriteRevert)
{
using (ImpersonateIdentity id = new ImpersonateIdentity(writeImpersonationBehavior))
{
writer.Write(bytesIn, 0, bytesRead);
}
}
else
{
writer.Write(bytesIn, 0, bytesRead);
}
}
}
dsToStream.Detach();
}
}
/// <summary>
/// If there is an m_result cached from a call to CreateManifestNavigator, return that manifest.
/// Otherwise, create a manifest using a relaxed conversion.
/// </summary>
/// <returns>Contents of the imsmanifest.xml converted from the index.xml.</returns>
internal Stream ConvertFromIndexXml()
{
ConversionResult result;
if (m_result == null || m_result.Manifest == null)
{
result = ManifestConverter.ConvertFromIndexXml(GetFileStream("index.xml"), GetFilePaths(),
true, ValidationBehavior.None);
}
else
{
result = m_result;
}
using(DetachableStream output = new DetachableStream(result.Manifest.OuterXml.Length))
{
using (XmlWriter writer = XmlWriter.Create(output))
{
result.Manifest.WriteSubtree(writer);
writer.Flush();
output.Detach();
}
output.Stream.Seek(0, SeekOrigin.Begin);
return output.Stream;
}
}
/// <summary>
/// Render the requested view into the output stream.
/// </summary>
/// <param name="context">The context within which to render the page.</param>
/// <remarks>
/// When this method returns the <paramref name="context"/> OutputStream will contain
/// the rendered file.
/// <p>
/// The following methods and properties must be return valid values from
/// the <paramref name="context"/>:
/// <ul>
/// <li>EmbeddedUiResourcePath, must be non-null</li>
/// <li>FormElementId</li>
/// <li>GetInputStream</li>
/// <li>OutputStream</li>
/// <li>View</li>
/// </ul>
/// </p>
/// <p>
/// Additionally, if the following properties are set, they will be used:
/// <ul>
/// <li>FormElementAction</li>
/// <li>HiddenControls</li>
/// <li>ScriptToRender</li>
/// </ul>
/// </p>
/// All other properties on <paramref name="context"/> are ignored.
/// </remarks>
/// <exception cref="FileNotFoundException">The requested file attachment can't be found.</exception>
public override void Render(RloRenderContext context)
{
AIResources.Culture = LocalizationManager.GetCurrentCulture();
// string is the key (which is AssessmentItem.Id_AssessmentItem.Type)
// int is the ordinal (0 based) which is the number of times the key has been processed
Dictionary <string, int> assessmentItems = new Dictionary <string, int>();
// The most common case is that the file is in the package
Stream inputStream = null;
AssessmentItemManager.DataModelContext = context;
LearningDataModel learningDataModel = context.LearningDataModel;
try
{
int srcIndex; // represents the index of the "src" attribute on an <img> node.
// If this is the first time the page is being rendered, parse the page and determine
// the interactions on the page.
if (context.View == SessionView.Execute)
{
if (!GetPageHasBeenVisited(learningDataModel))
{
using (inputStream = context.GetInputStream())
{
// If the file being requested is the default file for the current activity,
if (context.IsResourceEntryPoint)
{
// find all the assessment items (<IMG> tags that contain the text "mslamrk" as part of the src attribute.)
using (HtmlTextReader reader = new HtmlTextReader(inputStream))
{
while (reader.Read())
{
if (IsAITag(reader, out srcIndex))
{
try
{
AssessmentItem ai = AssessmentItem.Parse(reader.GetAttributeValue(srcIndex));
AssessmentItemRenderer renderer = AssessmentItemManager.GetRenderer(ai);
renderer.TryAddToDataModel();
}
catch (FormatException)
{
// skip this one. This is mirrored below in the 2nd pass.
}
}
}
}
}
}
SetPageHasBeenVisited(learningDataModel);
}
}
// must get the input stream again since it may not be possible to seek back to the beginning
using (inputStream = context.GetInputStream())
{
if (context.Response != null)
{
// Clear the output response
context.Response.Clear();
}
// If the file being requested is the default file for the current activity,
if (context.IsResourceEntryPoint)
{
if (context.View == SessionView.Execute)
{
// Set ExitMode to suspend so that when a student exits the activity it is left in a suspended state.
// This way if the activity is reactivated, the student's previous answers are intact.
learningDataModel.NavigationRequest.ExitMode = ExitMode.Suspended;
}
DetachableStream detachable = new DetachableStream(context.OutputStream);
// Parse through the input stream again, this time rendering into the output as we go.
using (StreamWriter writer = new StreamWriter(detachable))
{
using (HtmlTextReader reader = new HtmlTextReader(inputStream))
{
while (reader.Read())
{
if (IsAITag(reader, out srcIndex))
{
try
{
AssessmentItem ai = AssessmentItem.Parse(reader.GetAttributeValue(srcIndex));
AssessmentItemRenderer renderer = AssessmentItemManager.GetRenderer(ai);
if (assessmentItems.ContainsKey(ai.RenderKey))
{
assessmentItems[ai.RenderKey] += 1;
}
else
{
assessmentItems.Add(ai.RenderKey, 0);
}
writer.Write(renderer.Render(assessmentItems[ai.RenderKey]).ToString());
}
catch (FormatException)
{
// skip this one. This is mirrored above in the 1st pass.
}
}
else
{
HandleNode(reader, writer);
}
}
}
// don't allow closing the StreamWriter to close the context.OutputStream.
writer.Flush();
detachable.Detach();
}
// set the response type
context.SetOutputStreamExtension(Path.GetExtension(context.RelativePath));
}
else
{
// for a non-entry-point file, copy the file directly to the output stream
context.WriteFileToResponse(context.RelativePath);
}
}
return;
}
catch (FileNotFoundException)
{
// This means the requested file is not in the package. That's not necessarily a problem, since it
// may be a request for an attachment.
}
// We got here because the file is not in the package. In that case, render it if it is a file attachment
int beginAttachmentInfo = context.RelativePath.IndexOf("/~RLO/", StringComparison.Ordinal);
if (beginAttachmentInfo != -1)
{
// attachmentInfo should be of the form <interactionId>/<attachmentIndex>, so split it into the parts
string attachmentInfo = context.RelativePath.Substring(beginAttachmentInfo + 6);
RenderFileAttachment(context, attachmentInfo);
}
else
{
// This means the requested file is not in the package, nor is it a request for an attachment.
throw new FileNotFoundException(AIResources.FileNotFound);
}
}
/// <summary>
/// Writes the file from a byte array directly to the response. The output stream
/// extension must be set prior to calling this method.
/// If the response is provided and the path extension is not
/// in the list of files to use IIS compatibility mode, this is much faster than
/// copying the file contents to the output stream and should be used whenever possible.
/// If there is no response object, the method reverts to copying the file between streams.
/// </summary>
/// <param name="fileBytes">The file to render.</param>
internal void WriteFileToResponse(byte[] fileBytes)
{
using (Disposer disposer = new Disposer())
{
// Open a stream on the file. For some odd reason fxcop does not acknowledge the ability of disposer
// to actually dispose fileStream, so we give it its own using block.
using (Stream fileStream = new MemoryStream(fileBytes))
{
// If the response was provided (which it will be, in most non-test cases), then
// do the TransmitFile or WriteFile. Otherwise, copy the streams to the response output stream.
if (Response != null)
{
// IisCompatibilityMode is not considered here, because in no case do we have a file
// path that can be read by TransmitFile.
WriteIisCompatibilityModeToResponse(fileStream);
}
else
{
DetachableStream outputDS = new DetachableStream(OutputStream);
disposer.Push(outputDS);
Utilities.CopyStream(fileStream, ImpersonationBehavior.UseImpersonatedIdentity, outputDS, ImpersonationBehavior.UseImpersonatedIdentity);
outputDS.Detach();
}
}
}
}
/// <summary>
/// Writes the file from the package directly to the response and set the appropriate
/// content type in the response. If the response is provided and the path extension is not
/// in the list of files to use IIS compatibility mode, this is much faster than
/// copying the file contents to the output stream and should be used whenever possible.
/// If there is no response object, the method reverts to copying the file between streams.
/// </summary>
/// <param name="relativePath">The package-relative path to the file to render.</param>
internal void WriteFileToResponse(string relativePath)
{
// Set the mime type on the response
string pathExtension = Path.GetExtension(relativePath);
SetOutputStreamExtension(pathExtension);
using(Disposer disposer = new Disposer())
{
PackageReader pkgReader = m_session.GetPackageReader();
disposer.Push(pkgReader);
// If the response was provided (which it will be, in most non-test cases), then
// do the TransmitFile or WriteFile. Otherwise, copy the streams to the response output stream.
if (Response != null)
{
// If we are to use Compatibility mode, then write the file
if (UseCompatibilityMode(pathExtension))
{
Stream packageFile = pkgReader.GetFileStream(relativePath);
WriteIisCompatibilityModeToResponse(packageFile);
}
else
{
pkgReader.TransmitFile(relativePath, m_context.Response);
}
}
else
{
DetachableStream outputDS = new DetachableStream(OutputStream);
disposer.Push(outputDS);
Stream packageFile = pkgReader.GetFileStream(relativePath);
disposer.Push(packageFile);
Utilities.CopyStream(packageFile, ImpersonationBehavior.UseImpersonatedIdentity, outputDS, ImpersonationBehavior.UseImpersonatedIdentity);
outputDS.Detach();
}
}
}
/// <summary>
/// Render the requested view into the output stream.
/// </summary>
/// <param name="context">The context within which to render the page.</param>
/// <remarks>
/// When this method returns the <paramref name="context"/> OutputStream will contain
/// the rendered file.
/// <p>
/// The following methods and properties must be return valid values from
/// the <paramref name="context"/>:
/// <ul>
/// <li>EmbeddedUiResourcePath, must be non-null</li>
/// <li>FormElementId</li>
/// <li>GetInputStream</li>
/// <li>OutputStream</li>
/// <li>View</li>
/// </ul>
/// </p>
/// <p>
/// Additionally, if the following properties are set, they will be used:
/// <ul>
/// <li>FormElementAction</li>
/// <li>HiddenControls</li>
/// <li>ScriptToRender</li>
/// </ul>
/// </p>
/// All other properties on <paramref name="context"/> are ignored.
/// </remarks>
/// <exception cref="FileNotFoundException">The requested file attachment can't be found.</exception>
public override void Render(RloRenderContext context)
{
AIResources.Culture = LocalizationManager.GetCurrentCulture();
// string is the key (which is AssessmentItem.Id_AssessmentItem.Type)
// int is the ordinal (0 based) which is the number of times the key has been processed
Dictionary<string, int> assessmentItems = new Dictionary<string, int>();
// The most common case is that the file is in the package
Stream inputStream = null;
AssessmentItemManager.DataModelContext = context;
LearningDataModel learningDataModel = context.LearningDataModel;
try
{
int srcIndex; // represents the index of the "src" attribute on an <img> node.
// If this is the first time the page is being rendered, parse the page and determine
// the interactions on the page.
if (context.View == SessionView.Execute)
{
if (!GetPageHasBeenVisited(learningDataModel))
{
using (inputStream = context.GetInputStream())
{
// If the file being requested is the default file for the current activity,
if (context.IsResourceEntryPoint)
{
// find all the assessment items (<IMG> tags that contain the text "mslamrk" as part of the src attribute.)
using (HtmlTextReader reader = new HtmlTextReader(inputStream))
{
while (reader.Read())
{
if (IsAITag(reader, out srcIndex))
{
try
{
AssessmentItem ai = AssessmentItem.Parse(reader.GetAttributeValue(srcIndex));
AssessmentItemRenderer renderer = AssessmentItemManager.GetRenderer(ai);
renderer.TryAddToDataModel();
}
catch (FormatException)
{
// skip this one. This is mirrored below in the 2nd pass.
}
}
}
}
}
}
SetPageHasBeenVisited(learningDataModel);
}
}
// must get the input stream again since it may not be possible to seek back to the beginning
using (inputStream = context.GetInputStream())
{
if (context.Response != null)
{
// Clear the output response
context.Response.Clear();
}
// If the file being requested is the default file for the current activity,
if (context.IsResourceEntryPoint)
{
if (context.View == SessionView.Execute)
{
// Set ExitMode to suspend so that when a student exits the activity it is left in a suspended state.
// This way if the activity is reactivated, the student's previous answers are intact.
learningDataModel.NavigationRequest.ExitMode = ExitMode.Suspended;
}
DetachableStream detachable = new DetachableStream(context.OutputStream);
// Parse through the input stream again, this time rendering into the output as we go.
using (StreamWriter writer = new StreamWriter(detachable))
{
using (HtmlTextReader reader = new HtmlTextReader(inputStream))
{
while (reader.Read())
{
if (IsAITag(reader, out srcIndex))
{
try
{
AssessmentItem ai = AssessmentItem.Parse(reader.GetAttributeValue(srcIndex));
AssessmentItemRenderer renderer = AssessmentItemManager.GetRenderer(ai);
if (assessmentItems.ContainsKey(ai.RenderKey))
{
assessmentItems[ai.RenderKey] += 1;
}
else
{
assessmentItems.Add(ai.RenderKey, 0);
}
writer.Write(renderer.Render(assessmentItems[ai.RenderKey]).ToString());
}
catch (FormatException)
{
// skip this one. This is mirrored above in the 1st pass.
}
}
else
{
HandleNode(reader, writer);
}
}
}
// don't allow closing the StreamWriter to close the context.OutputStream.
writer.Flush();
detachable.Detach();
}
// set the response type
context.SetOutputStreamExtension(Path.GetExtension(context.RelativePath));
}
else
{
// for a non-entry-point file, copy the file directly to the output stream
context.WriteFileToResponse(context.RelativePath);
}
}
return;
}
catch (FileNotFoundException)
{
// This means the requested file is not in the package. That's not necessarily a problem, since it
// may be a request for an attachment.
}
// We got here because the file is not in the package. In that case, render it if it is a file attachment
int beginAttachmentInfo = context.RelativePath.IndexOf("/~RLO/", StringComparison.Ordinal);
if (beginAttachmentInfo != -1)
{
// attachmentInfo should be of the form <interactionId>/<attachmentIndex>, so split it into the parts
string attachmentInfo = context.RelativePath.Substring(beginAttachmentInfo + 6);
RenderFileAttachment(context, attachmentInfo);
}
else
{
// This means the requested file is not in the package, nor is it a request for an attachment.
throw new FileNotFoundException(AIResources.FileNotFound);
}
}
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2000:DisposeObjectsBeforeLosingScope")] // the writer is disposed for all code paths
internal static void CopyStream(Stream fromStream, ImpersonationBehavior readImpersonationBehavior, Stream toStream, ImpersonationBehavior writeImpersonationBehavior)
{
using (Disposer disposer = new Disposer())
{
DetachableStream dsToStream = new DetachableStream(toStream);
disposer.Push(dsToStream);
BinaryWriter writer = new BinaryWriter(dsToStream);
disposer.Push(writer);
// An addition revert during write operations is required if the setting for reading and writing
// is not the same
bool requiresWriteRevert = (readImpersonationBehavior != writeImpersonationBehavior);
using (ImpersonateIdentity readId = new ImpersonateIdentity(readImpersonationBehavior))
{
byte[] bytesIn = new byte[65536];
int bytesRead;
while ((bytesRead = fromStream.Read(bytesIn, 0, bytesIn.Length)) != 0)
{
// If we have to impersonate to write, then do it. Otherwise skip it.
if (requiresWriteRevert)
{
using (ImpersonateIdentity id = new ImpersonateIdentity(writeImpersonationBehavior))
{
writer.Write(bytesIn, 0, bytesRead);
}
}
else
{
writer.Write(bytesIn, 0, bytesRead);
}
}
}
dsToStream.Detach();
}
}
