private void CompressContent(HttpApplication httpApplication)
{
if (!httpApplication.Context.Items.Contains("__@fluorinehttpcompress"))
{
httpApplication.Context.Items.Add("__@fluorinehttpcompress", 1);
HttpCompressSettings httpCompressSettings = FluorineConfiguration.Instance.HttpCompressSettings;
if (((httpCompressSettings.HandleRequest != HandleRequest.None) && ((httpCompressSettings.HandleRequest != HandleRequest.Amf) || !(httpApplication.Request.ContentType != "application/x-amf"))) && (httpCompressSettings.CompressionLevel != CompressionLevels.None))
{
string fileName = Path.GetFileName(httpApplication.Request.Path);
if (!httpCompressSettings.IsExcludedPath(fileName) && ((httpApplication.Response.ContentType != null) && !httpCompressSettings.IsExcludedMimeType(httpApplication.Response.ContentType)))
{
httpApplication.Response.Cache.VaryByHeaders["Accept-Encoding"] = true;
string str2 = httpApplication.Request.Headers["Accept-Encoding"];
if (str2 != null)
{
CompressingFilter compressStream = GetFilterForScheme(str2.Split(new char[] { ',' }), httpApplication.Response.Filter, httpCompressSettings);
if (compressStream != null)
{
if (httpApplication.Request.ContentType == "application/x-amf")
{
httpApplication.Response.Filter = new ThresholdFilter(compressStream, httpApplication.Response.Filter, httpCompressSettings.Threshold);
}
else
{
httpApplication.Response.Filter = compressStream;
}
}
}
}
}
}
}
/// <summary>
/// Get ahold of a <see cref="CompressingFilter"/> for the given encoding scheme.
/// If no encoding scheme can be found, it returns null.
/// </summary>
/// <remarks>
/// See http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.3 for details
/// on how clients are supposed to construct the Accept-Encoding header. This
/// implementation follows those rules, though we allow the server to override
/// the preference given to different supported algorithms. I'm doing this as
/// I would rather give the server control over the algorithm decision than
/// the client. If the clients send up * as an accepted encoding with highest
/// quality, we use the preferred algorithm as specified in the config file.
/// </remarks>
internal static CompressingFilter GetFilterForScheme(string[] schemes, Stream output, HttpCompressSettings prefs)
{
bool foundDeflate = false;
bool foundGZip = false;
bool foundStar = false;
float deflateQuality = 0f;
float gZipQuality = 0f;
float starQuality = 0f;
for (int i = 0; i < schemes.Length; i++)
{
string acceptEncodingValue = schemes[i].Trim().ToLower();
if (acceptEncodingValue.StartsWith("deflate"))
{
foundDeflate = true;
float newDeflateQuality = GetQuality(acceptEncodingValue);
if (deflateQuality < newDeflateQuality)
{
deflateQuality = newDeflateQuality;
}
}
else if (acceptEncodingValue.StartsWith("gzip") || acceptEncodingValue.StartsWith("x-gzip"))
{
foundGZip = true;
float newGZipQuality = GetQuality(acceptEncodingValue);
if (gZipQuality < newGZipQuality)
{
gZipQuality = newGZipQuality;
}
}
else if (acceptEncodingValue.StartsWith("*"))
{
foundStar = true;
float newStarQuality = GetQuality(acceptEncodingValue);
if (starQuality < newStarQuality)
{
starQuality = newStarQuality;
}
}
}
bool isAcceptableStar = foundStar && (starQuality > 0);
bool isAcceptableDeflate = (foundDeflate && (deflateQuality > 0)) || (!foundDeflate && isAcceptableStar);
bool isAcceptableGZip = (foundGZip && (gZipQuality > 0)) || (!foundGZip && isAcceptableStar);
if (isAcceptableDeflate && !foundDeflate)
{
deflateQuality = starQuality;
}
if (isAcceptableGZip && !foundGZip)
{
gZipQuality = starQuality;
}
// Do they support any of our compression methods?
if (!(isAcceptableDeflate || isAcceptableGZip || isAcceptableStar))
{
return(null);
}
// If deflate is better according to client
if (isAcceptableDeflate && (!isAcceptableGZip || (deflateQuality > gZipQuality)))
{
return(new DeflateFilter(output, prefs.CompressionLevel));
}
// If gzip is better according to client
if (isAcceptableGZip && (!isAcceptableDeflate || (deflateQuality < gZipQuality)))
{
return(new GZipFilter(output));
}
// If we're here, the client either didn't have a preference or they don't support compression
if (isAcceptableDeflate && (prefs.PreferredAlgorithm == Algorithms.Deflate || prefs.PreferredAlgorithm == Algorithms.Default))
{
return(new DeflateFilter(output, prefs.CompressionLevel));
}
if (isAcceptableGZip && prefs.PreferredAlgorithm == Algorithms.GZip)
{
return(new GZipFilter(output));
}
if (isAcceptableDeflate || isAcceptableStar)
{
return(new DeflateFilter(output, prefs.CompressionLevel));
}
if (isAcceptableGZip)
{
return(new GZipFilter(output));
}
// return null. we couldn't find a filter.
return(null);
}
/// <summary>
/// EventHandler that gets ahold of the current request context and attempts to compress the output.
/// </summary>
/// <param name="httpApplication">The <see cref="HttpApplication"/> that is firing this event.</param>
public void CompressContent(HttpApplication httpApplication)
{
// Only do this if we haven't already attempted an install. This prevents PreSendRequestHeaders from
// trying to add this item way to late. We only want the first run through to do anything.
// also, we use the context to store whether or not we've attempted an add, as it's thread-safe and
// scoped to the request. An instance of this module can service multiple requests at the same time,
// so we cannot use a member variable.
if (!httpApplication.Context.Items.Contains(FluorineHttpCompressKey))
{
// Log the install attempt in the HttpContext. Must do this first as several IF statements below skip full processing of this method
httpApplication.Context.Items.Add(FluorineHttpCompressKey, 1);
// Get the config settings
HttpCompressSettings settings = FluorineConfiguration.Instance.HttpCompressSettings;
// Skip if no request can be handled
if (settings.HandleRequest == HandleRequest.None)
{
return;
}
// Skip if only AMF is compressed and we do not have an AMF request
if (settings.HandleRequest == HandleRequest.Amf && httpApplication.Request.ContentType != ContentType.AMF)
{
return;
}
// Skip if the CompressionLevel is set to 'None'
if (settings.CompressionLevel == CompressionLevels.None)
{
return;
}
//string realPath = httpApplication.Request.Path.Remove(0, httpApplication.Request.ApplicationPath.Length+1);
string realPath = Path.GetFileName(httpApplication.Request.Path);
if (settings.IsExcludedPath(realPath))
{
// Skip if the file path excludes compression
return;
}
// Skip if the MimeType excludes compression
if (httpApplication.Response.ContentType == null || settings.IsExcludedMimeType(httpApplication.Response.ContentType))
{
return;
}
// Fix to handle caching appropriately, see http://www.pocketsoap.com/weblog/2003/07/1330.html
// This header is added only when the request has the possibility of being compressed
// i.e. it is not added when the request is excluded from compression by CompressionLevel, Path, or MimeType
httpApplication.Response.Cache.VaryByHeaders["Accept-Encoding"] = true;
// Grab an array of algorithm;q=x, algorith;q=x style values
string acceptedTypes = httpApplication.Request.Headers["Accept-Encoding"];
// If we couldn't find the header, bail out
if (acceptedTypes == null)
{
return;
}
// The actual types could be , delimited. split 'em out.
string[] types = acceptedTypes.Split(',');
CompressingFilter filter = GetFilterForScheme(types, httpApplication.Response.Filter, settings);
// If we didn't find a filter, bail out
if (filter == null)
{
return;
}
// If we get here, we found a viable filter.
// Set the filter and change the Content-Encoding header to match so the client can decode the response
if (httpApplication.Request.ContentType == ContentType.AMF)
{
httpApplication.Response.Filter = new ThresholdFilter(filter, httpApplication.Response.Filter, settings.Threshold);
}
else
{
httpApplication.Response.Filter = filter;
}
}
}
/// <summary>
/// Get ahold of a <see cref="CompressingFilter"/> for the given encoding scheme.
/// If no encoding scheme can be found, it returns null.
/// </summary>
/// <remarks>
/// See http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.3 for details
/// on how clients are supposed to construct the Accept-Encoding header. This
/// implementation follows those rules, though we allow the server to override
/// the preference given to different supported algorithms. I'm doing this as
/// I would rather give the server control over the algorithm decision than
/// the client. If the clients send up * as an accepted encoding with highest
/// quality, we use the preferred algorithm as specified in the config file.
/// </remarks>
internal static CompressingFilter GetFilterForScheme(string[] schemes, Stream output, HttpCompressSettings prefs)
{
bool foundDeflate = false;
bool foundGZip = false;
bool foundStar = false;
float deflateQuality = 0f;
float gZipQuality = 0f;
float starQuality = 0f;
for (int i = 0; i<schemes.Length;i++)
{
string acceptEncodingValue = schemes[i].Trim().ToLower();
if (acceptEncodingValue.StartsWith("deflate"))
{
foundDeflate = true;
float newDeflateQuality = GetQuality(acceptEncodingValue);
if (deflateQuality < newDeflateQuality)
deflateQuality = newDeflateQuality;
}
else if (acceptEncodingValue.StartsWith("gzip") || acceptEncodingValue.StartsWith("x-gzip"))
{
foundGZip = true;
float newGZipQuality = GetQuality(acceptEncodingValue);
if (gZipQuality < newGZipQuality)
gZipQuality = newGZipQuality;
}
else if (acceptEncodingValue.StartsWith("*"))
{
foundStar = true;
float newStarQuality = GetQuality(acceptEncodingValue);
if (starQuality < newStarQuality)
starQuality = newStarQuality;
}
}
bool isAcceptableStar = foundStar && (starQuality > 0);
bool isAcceptableDeflate = (foundDeflate && (deflateQuality > 0)) || (!foundDeflate && isAcceptableStar);
bool isAcceptableGZip = (foundGZip && (gZipQuality > 0)) || (!foundGZip && isAcceptableStar);
if (isAcceptableDeflate && !foundDeflate)
deflateQuality = starQuality;
if (isAcceptableGZip && !foundGZip)
gZipQuality = starQuality;
// Do they support any of our compression methods?
if(!(isAcceptableDeflate || isAcceptableGZip || isAcceptableStar))
return null;
// If deflate is better according to client
if (isAcceptableDeflate && (!isAcceptableGZip || (deflateQuality > gZipQuality)))
return new DeflateFilter(output, prefs.CompressionLevel);
// If gzip is better according to client
if (isAcceptableGZip && (!isAcceptableDeflate || (deflateQuality < gZipQuality)))
return new GZipFilter(output);
// If we're here, the client either didn't have a preference or they don't support compression
if(isAcceptableDeflate && (prefs.PreferredAlgorithm == Algorithms.Deflate || prefs.PreferredAlgorithm == Algorithms.Default))
return new DeflateFilter(output, prefs.CompressionLevel);
if(isAcceptableGZip && prefs.PreferredAlgorithm == Algorithms.GZip)
return new GZipFilter(output);
if(isAcceptableDeflate || isAcceptableStar)
return new DeflateFilter(output, prefs.CompressionLevel);
if(isAcceptableGZip)
return new GZipFilter(output);
// return null. we couldn't find a filter.
return null;
}
internal static CompressingFilter GetFilterForScheme(string[] schemes, Stream output, HttpCompressSettings prefs)
{
bool flag = false;
bool flag2 = false;
bool flag3 = false;
float num = 0f;
float num2 = 0f;
float num3 = 0f;
for (int i = 0; i < schemes.Length; i++)
{
string acceptEncodingValue = schemes[i].Trim().ToLower();
if (acceptEncodingValue.StartsWith("deflate"))
{
flag = true;
float quality = GetQuality(acceptEncodingValue);
if (num < quality)
{
num = quality;
}
}
else if (acceptEncodingValue.StartsWith("gzip") || acceptEncodingValue.StartsWith("x-gzip"))
{
flag2 = true;
float num6 = GetQuality(acceptEncodingValue);
if (num2 < num6)
{
num2 = num6;
}
}
else if (acceptEncodingValue.StartsWith("*"))
{
flag3 = true;
float num7 = GetQuality(acceptEncodingValue);
if (num3 < num7)
{
num3 = num7;
}
}
}
bool flag6 = flag3 && (num3 > 0f);
bool flag4 = (flag && (num > 0f)) || (!flag && flag6);
bool flag5 = (flag2 && (num2 > 0f)) || (!flag2 && flag6);
if (!(!flag4 || flag))
{
num = num3;
}
if (!(!flag5 || flag2))
{
num2 = num3;
}
if ((flag4 || flag5) || flag6)
{
if (flag4 && (!flag5 || (num > num2)))
{
return(new DeflateFilter(output, prefs.CompressionLevel));
}
if (flag5 && (!flag4 || (num < num2)))
{
return(new GZipFilter(output));
}
if (flag4 && ((prefs.PreferredAlgorithm == Algorithms.Deflate) || (prefs.PreferredAlgorithm == Algorithms.Default)))
{
return(new DeflateFilter(output, prefs.CompressionLevel));
}
if (flag5 && (prefs.PreferredAlgorithm == Algorithms.GZip))
{
return(new GZipFilter(output));
}
if (flag4 || flag6)
{
return(new DeflateFilter(output, prefs.CompressionLevel));
}
if (flag5)
{
return(new GZipFilter(output));
}
}
return(null);
}
