/// <summary>
/// Get the info about the resource that in the assembly
/// </summary>
/// <param name="assembly"></param>
/// <param name="resourceName"></param>
/// <returns></returns>
protected static Quadruplet <bool, bool, string, bool> GetResourceInfo(Assembly assembly, string resourceName)
{
// Create a unique cache key
var cacheKey = CombineHashCodes(assembly.GetHashCode(), resourceName.GetHashCode());
var resourceInfo = WebResourceCache[cacheKey] as Quadruplet <bool, bool, string, bool>;
// Assembly info was not in the cache
if (resourceInfo == null)
{
var first = false;
var second = false;
var third = string.Empty;
var forth = false;
var customAttributes = assembly.GetCustomAttributes(false);
for (var j = 0; j < customAttributes.Length; j++)
{
var attribute = customAttributes[j] as WebResourceAttribute;
if ((attribute == null) || !string.Equals(attribute.WebResource, resourceName, StringComparison.Ordinal))
{
continue;
}
first = true;
second = attribute.PerformSubstitution;
third = attribute.ContentType;
forth = CompressionModuleHelper.IsContentTypeCompressible(attribute.ContentType);
break;
}
resourceInfo = new Quadruplet <bool, bool, string, bool>(first, second, third, forth);
WebResourceCache[cacheKey] = resourceInfo;
}
return(resourceInfo);
}
/// <summary>
/// Write a StreamReader to an outpit stream
/// </summary>
/// <param name="reader"></param>
/// <param name="context"></param>
protected static void CompressAndWriteToStream(StreamReader reader, HttpContext context)
{
var compressionType = CompressionModuleHelper.IsSpecificEncodingSupported(context, CompressionModuleHelper.GZIP) ? CompressionModuleHelper.GZIP : CompressionModuleHelper.DEFLATE;
CompressionModuleHelper.SetEncodingType(context.Response, compressionType);
// All the supported content for compression can be read as string, so we use reader.ReadToEnd()
var compressed = CompressionModuleHelper.Compressor(reader.ReadToEnd(), compressionType);
context.Response.OutputStream.Write(compressed, 0, compressed.Length);
reader.Dispose();
}
protected static void OnPostAcquireRequestState(object sender, EventArgs e)
{
var httpContext = HttpContext.Current;
// This part of the module compress only handlers from type System.Web.UI.Page
// Other types such JavaScript or CSS files will be compressed in an httpHandler.
// Here we check if the current handler if a Page, if so, we compress it.
// Because there is a problem with async postbacks compression, we check here if the current request if an 'MS AJAX' call.
// If so, we will not compress it.
// Important !!! : I didn't check this module with another Ajax frameworks such 'infragistics' or 'SmartClient'.
// probably you will have to change the IsAjaxPostBackRequest method.
if (!(httpContext.CurrentHandler is Page || httpContext.CurrentHandler.GetType().BaseType.FullName == "System.Web.Mvc.MvcHandler") || CompressionModuleHelper.IsAjaxPostBackRequest(httpContext))
{
return;
}
if (!CompressionModuleHelper.IsCompressionSupported(httpContext, true))
{
return;
}
var response = httpContext.Response;
// Check if GZIP is supported by the client
if (CompressionModuleHelper.IsSpecificEncodingSupported(httpContext, CompressionModuleHelper.GZIP))
{
response.Filter = new GZipStream(response.Filter, CompressionMode.Compress);
CompressionModuleHelper.SetEncodingType(response, CompressionModuleHelper.GZIP);
}
// If GZIP is not supported, so only DEFLATE is.
else
{
response.Filter = new DeflateStream(response.Filter, CompressionMode.Compress);
CompressionModuleHelper.SetEncodingType(response, CompressionModuleHelper.DEFLATE);
}
}
protected static void OnPreRequestHandlerExecute(object sender, EventArgs e)
{
var httpApplication = (HttpApplication)sender;
var httpContext = httpApplication.Context;
if (!(httpContext.CurrentHandler is AssemblyResourceLoader))
{
return;
}
var response = httpContext.Response;
var request = httpContext.Request;
var etag = (request.QueryString.ToString()).GetHashCode().ToString();
// Check if the ETag is match. If so, we don't send nothing to the client, and stop here.
CheckETag(httpApplication, etag);
try
{
// Parse the QueryString into parts
var urlInfo = GetDataFromQuery(httpApplication.Context.Request.QueryString);
// Load the assembly
var assembly = GetAssembly(urlInfo.First, urlInfo.Second);
if (assembly == null)
{
ThrowHttpException(404, SR.WebResourceCompressionModuleAssemblyNotFound, urlInfo.Forth);
}
//var lastModified = File.GetLastWriteTimeUtc(assembly.Location);
// Get the resource info from assembly.
var resourceInfo = GetResourceInfo(assembly, urlInfo.Third);
if (!resourceInfo.First)
{
ThrowHttpException(404, SR.WebResourceCompressionModuleAssemblyNotFound, urlInfo.Forth);
}
// If the WebResource needs to perform substitution (WebResource inside WebResource), we leave it to the original AssemblyResourceLoader handler ;-)
if (resourceInfo.Second)
{
return;
}
response.Clear();
// Set the response cache headers
SetCachingHeadersForWebResource(response.Cache, etag, Expires);
// Set the response content type
response.ContentType = resourceInfo.Third;
// Write content with compression
if (resourceInfo.Forth && CompressionModuleHelper.IsCompressionSupported(httpContext, false))
{
using (var resourceStream = new StreamReader(assembly.GetManifestResourceStream(urlInfo.Third), true))
{
CompressAndWriteToStream(resourceStream, httpApplication.Context);
}
}
// Write content without compression
else
{
using (var resourceStream = assembly.GetManifestResourceStream(urlInfo.Third))
{
WriteToStream(resourceStream, response.OutputStream);
}
}
response.OutputStream.Flush();
httpApplication.CompleteRequest();
}
catch (ArgumentNullException)
{
return;
}
catch (TargetInvocationException)
{
return;
}
catch (System.Security.Cryptography.CryptographicException)
{
return;
}
}