/// <summary>
/// Loads the appropriate xml file and loads the IFileInstruction
/// </summary>
/// <param name="context">httpcontext</param>
/// <param name="url">Requested URL</param>
void RewriteUrl(HttpContext context, string url)
{
if (url.EndsWith("/")) //The key will never be just / because of the statement above
{
//strip the trailing /
url = url.Substring(0, url.LastIndexOf('/'));
}
//Store the url so it can be rewritten for logging.
context.Items[REQUEST_URL_KEY] = url;
IFileInstruction fileInstruction = null;
try
{
//Load the XML file to create a file instruction object of type IFileInstruction.If the XML file fails to create IFileInstruction
//Object log error
fileInstruction = FileInstructionFactory.GetFileInstruction(url);
}
catch (Exception ex)
{
log.Error("RewriteUrl(): Requested URL: " + context.Items[REQUEST_URL_KEY] + "\nFailed to Create IFileInstruction with the XML file Provided.", ex);
RaiseErrorPage();
return;
}
//Exiting because there is no page assembly instruction for the requested URL.
if (fileInstruction == null)
{
return;
}
// Do not reset the client path because it'll break form action url's.
try
{
//If we should not index this item, then add the X-Robots-Tag header. This works
//just like the <meta name="robots"> tag.
if (fileInstruction.DoNotIndex)
{
context.Response.AppendHeader("X-Robots-Tag", "noindex, nofollow");
}
context.RewritePath(fileInstruction.FilePath, false);
}
catch (HttpException ex)
{
log.Error("RewriteUrl(): Requested URL: " + context.Items[REQUEST_URL_KEY] + "\nFailed to rewrite URL.", ex);
RaiseErrorPage();
}
}
/// <summary>
/// Creates an IFileInstruction derived instance from the XML at the specified path. ///
///
/// </summary>
public static IFileInstruction GetFileInstruction(string requestedPath)
{
bool isFileInstructionXmlValid = true;
string xmlFilePath = HttpContext.Current.Server.MapPath(String.Format(ContentDeliveryEngineConfig.PathInformation.FilePathFormat.Path, requestedPath));
// Input validation.
if (xmlFilePath == null)
{
throw new ArgumentNullException("pathToXml", "The pathToXml parameter cannot be null.");
}
if (!File.Exists(xmlFilePath))
{
return(null);
}
if (ContentDeliveryEngineConfig.FileInstruction.FileInstructionTypes.EnableValidation == true)
{
isFileInstructionXmlValid = FileInstructionFactory.ValidateXml(xmlFilePath,
HttpContext.Current.Server.MapPath(ContentDeliveryEngineConfig.FileInstruction.FileInstructionTypes.XsdPath));
}
if (isFileInstructionXmlValid == false)
{
return(null);
}
// Load the XML file into an XmlReader and create a IFileInstruction derived instance from the XML.
IFileInstruction fileInstruction = null;
try
{
using (FileStream xmlFile = File.Open(xmlFilePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite | FileShare.Delete))
{
using (XmlReader xmlReader = XmlReader.Create(xmlFile))
{
// Read just enough to get the file instruction type we want to create
// e.g. a GenericFileInstruction, etc.
xmlReader.MoveToContent();
// Get the name of the serializer type we need (the document element name is the
// name of the type).
string fileInstructionTypeName = xmlReader.LocalName;
// Make sure the serializer we need is in the cache (if it isn't, we've got invalid XML).
if (Instance._serializers.ContainsKey(fileInstructionTypeName) == false)
{
string message = String.Format("Unable to find XmlSerializer for type \"{0}.\" Either \"{0}\" is an unsupported type and the XML file at \"{1}\" is invalid or the file instruction configuration needs a new entry to support \"{0}\"", fileInstructionTypeName, xmlFilePath);
throw new FileInstructionException(message);
}
// Get the serializer from the cache.
XmlSerializer serializer = Instance._serializers[fileInstructionTypeName];
// Deserialize the XML into an object.
fileInstruction = (IFileInstruction)serializer.Deserialize(xmlReader);
}
}
}
catch (Exception ex)
{
throw new FileInstructionException(String.Format("Unable to create IFileInstruction for file \"{0}.\"", xmlFilePath), ex);
}
return(fileInstruction);
}
