I have web application that in some pages I use Ms Ajax (Script Manager,Update Panel,...). In these pages I can't use compression because it conflicts with *.axd files.
How I can compress specific pages in my web application?
I use a Http module to handle my compression. I am unable to use the new IIS compression for one of my sites since it is on shared hosting and they have not enabled IIS compression. I also have a custom web.config section in which i can exclude specific file paths as in:
If you want the code for module let me know. I can post it too. One class actually does the compression while i use 3 other classes to handle the custom web.config section.
<RiderDesign>
<HttpCompressionSettings compressionOn="true">
<includedFileTypes>
<add value="text/html"/>
<add value="text/xhtml"/>
</includedFileTypes>
<excludedFilePaths>
<add value="~/demos/partialpageupdates.aspx"/>
<add value="~/demos/inlinetextedit.aspx"/>
</excludedFilePaths>
</HttpCompressionSettings
</RiderDesign>
Just specify the pages to be excluded and they are not compressed.
My compression module is below:
Imports System.Web
Imports System.IO
Imports System.Net
Imports System.IO.Compression
Namespace RiderDesign.FrameworkV4.HttpModule
Public NotInheritable Class HttpCompressionModule
Implements IHttpModule
Private Shared GZIP As String = "gzip"
Private Shared DEFLATE As String = "deflate"
Private Shared ENCODING_TYPE As String = "encodingType"
Private Shared CONTENT_TYPE As String = "contentType"
Private MARK As String = "passedModule"
Dim HttpState As HttpCompressionConfigStateModule
Sub Dispose() Implements IHttpModule.Dispose
End Sub
Sub Init(ByVal context As HttpApplication) Implements IHttpModule.Init
If HttpCompressionConfigModule.GetConfig().CompressionOn = True Then
' Use for any other then WebResource
AddHandler context.PostReleaseRequestState, AddressOf context_PostReleaseRequestState
End If
If HttpCompressionConfigModule.GetConfig().CompressionOn = True Then
' Use only for WebResource.axd files
AddHandler context.BeginRequest, AddressOf context_BeginRequest
AddHandler context.EndRequest, AddressOf context_EndRequest
End If
End Sub 'IHttpModule.Init
Sub context_PostReleaseRequestState(ByVal sender As Object, ByVal e As EventArgs)
Dim app As HttpApplication = CType(sender, HttpApplication) '
If TypeOf app.Context.CurrentHandler Is System.Web.UI.Page And app.Request("HTTP_X_MICROSOFTAJAX") Is Nothing Then
Dim FilePath As String
Dim FilePaths As List(Of String) = New List(Of String)
For Each Me.HttpState In HttpCompressionConfigModule.GetConfig().ExcludedFilePaths
FilePaths.Add(String.Format("{0}", HttpState.Value))
Next HttpState
FilePath = String.Join(", ", FilePaths.ToArray())
Dim ContentTypes As String
Dim FileTypes As List(Of String) = New List(Of String)
Dim state As HttpCompressionConfigStateModule
For Each state In HttpCompressionConfigModule.GetConfig().IncludedFileTypes
FileTypes.Add(String.Format("{0}", state.Value))
Next state
ContentTypes = String.Join(", ", FileTypes.ToArray())
' Check if the path is not excluded.
If FilePath.Contains(app.Request.AppRelativeCurrentExecutionFilePath) Then
Return
End If
' Check if the mime type is not excluded. (Use to exclude pages that generate specific mime type (such image or Excel...))
If Not ContentTypes.Contains(app.Response.ContentType) Then
Return
End If
' Check if GZIP is supported by the client
If IsGzipEncodingSupported() Then
app.Response.Filter = New GZipStream(app.Response.Filter, CompressionMode.Compress)
SetEncodingType(GZIP)
' Check if DEFLATE is supported by the client
Else
If IsDeflateEncodingSupported() Then
app.Response.Filter = New DeflateStream(app.Response.Filter, CompressionMode.Compress)
SetEncodingType(DEFLATE)
End If
End If
End If
End Sub
Sub context_BeginRequest(ByVal sender As Object, ByVal e As EventArgs)
Dim app As HttpApplication = CType(sender, HttpApplication) '
'
' Check if the current request is WebResource.axd
If app.Request.Path.Contains("WebResource.axd") Then
SetCachingHeaders(app)
If app.Context.Request.QueryString(MARK) Is Nothing Then
app.CompleteRequest()
End If
End If
End Sub 'context_BeginRequest
Sub context_EndRequest(ByVal sender As Object, ByVal e As EventArgs)
Dim app As HttpApplication = CType(sender, HttpApplication) '
If app.Request.Path.Contains("WebResource.axd") And app.Context.Request.QueryString(MARK) Is Nothing Then
Dim cacheKey As String = app.Request.QueryString.ToString()
If app.Application(cacheKey) Is Nothing Then
CompressedIntoCache(app, cacheKey)
End If
SetEncodingType(CStr(app.Application((cacheKey + ENCODING_TYPE))))
app.Context.Response.ContentType = CStr(app.Application((cacheKey + CONTENT_TYPE)))
app.Context.Response.BinaryWrite(CType(app.Application(cacheKey), Byte()))
End If
End Sub 'context_EndRequest
Private Sub CompressedIntoCache(ByVal app As HttpApplication, ByVal cacheKey As String)
'Mark the current request by adding QueryString parameter.
Dim request As HttpWebRequest = CType(WebRequest.Create((app.Context.Request.Url.OriginalString + "&" + MARK + "=1")), HttpWebRequest)
request.Credentials = CredentialCache.DefaultNetworkCredentials
Using response As HttpWebResponse = CType(request.GetResponse, HttpWebResponse)
If (True) Then
' We getting the response stream, that raise again the 'BeginRequest' event (that why we marked the request)
Dim responseStream As Stream = response.GetResponseStream()
Dim contentType As String = response.ContentType.ToLower()
' Not a javascript or css content.
' We compress only WebResources that are Javascript or css file.
' The problem is, that we can know the content type only after we got the response. TODO: find a better solution
' for non CSS or JS content
If Not IsContentSupported(contentType) Then
' Set the response type
app.Context.Response.ContentType = contentType
' Send the file to the client without compression
StreamCopy(responseStream, app.Response.OutputStream)
responseStream.Dispose()
app.Context.Response.End()
Return
End If
' Copy the response stream into memory stream, so we can convert it into byte[] easly.
Dim dataStream As New MemoryStream()
StreamCopy(responseStream, dataStream)
responseStream.Dispose()
' Convert the response into byte[]
Dim data As Byte() = dataStream.ToArray()
dataStream.Dispose()
Dim encodingType As String = String.Empty
Using memstream As MemoryStream = New MemoryStream
Dim compress As Stream = Nothing
' Choose the compression type and make the compression
If IsGzipEncodingSupported() Then
compress = New GZipStream(memstream, CompressionMode.Compress)
encodingType = GZIP
Else
If IsDeflateEncodingSupported() Then
compress = New DeflateStream(memstream, CompressionMode.Compress)
encodingType = DEFLATE
End If
End If
compress.Write(data, 0, data.Length)
compress.Dispose()
app.Application.Lock()
app.Application.Add(cacheKey, memstream.ToArray())
app.Application.Add(cacheKey + ENCODING_TYPE, encodingType)
app.Application.Add(cacheKey + CONTENT_TYPE, response.ContentType)
app.Application.UnLock()
End Using
End If
End Using
End Sub 'CompressedIntoCache
Private Shared Sub StreamCopy(ByVal input As Stream, ByVal output As Stream)
Dim buffer(2048) As Byte
Dim read As Integer
Do
read = input.Read(buffer, 0, buffer.Length)
output.Write(buffer, 0, read)
Loop While read > 0
End Sub 'StreamCopy
Private Shared Sub SetCachingHeaders(ByVal app As HttpApplication)
Dim etag As String = """" + app.Context.Request.QueryString.ToString().GetHashCode().ToString() + """"
Dim incomingEtag As String = app.Request.Headers("If-None-Match")
app.Response.Cache.VaryByHeaders("Accept-Encoding") = True
app.Response.Cache.SetExpires(DateTime.Now.ToUniversalTime().AddDays(365))
app.Response.Cache.SetCacheability(HttpCacheability.Public)
app.Response.Cache.SetLastModified(DateTime.Now.ToUniversalTime().AddDays(-1))
app.Response.Cache.SetETag(etag)
If [String].Compare(incomingEtag, etag) = 0 Then
app.Response.StatusCode = CInt(HttpStatusCode.NotModified)
app.Response.End()
End If
End Sub 'SetCachingHeaders
Private Shared Function IsBrowserSupported() As Boolean
' Because bug in Internet Explorer 6
Return Not (HttpContext.Current.Request.UserAgent Is Nothing Or HttpContext.Current.Request.UserAgent.Contains("MSIE 6"))
End Function 'IsBrowserSupported
Private Shared Function IsEncodingSupported() As Boolean
Return IsGzipEncodingSupported() Or IsDeflateEncodingSupported()
End Function 'IsEncodingSupported
Private Shared Function IsGzipEncodingSupported() As Boolean
Return Not (HttpContext.Current.Request.Headers("Accept-encoding") Is Nothing) And HttpContext.Current.Request.Headers("Accept-encoding").Contains(GZIP)
End Function 'IsGzipEncodingSupported
Private Shared Function IsDeflateEncodingSupported() As Boolean
Return Not (HttpContext.Current.Request.Headers("Accept-encoding") Is Nothing) And HttpContext.Current.Request.Headers("Accept-encoding").Contains(DEFLATE)
End Function 'IsDeflateEncodingSupported
Private Shared Sub SetEncodingType(ByVal encoding As String)
HttpContext.Current.Response.AppendHeader("Content-encoding", encoding)
End Sub 'SetEncodingType
Private Shared Function IsContentSupported(ByVal contentType As String) As Boolean
If contentType.Contains("text/css") Or contentType.Contains("javascript") Then
Return True
End If
Return False
End Function
End Class
End Namespace