SQL Server 2008 and 2008 R2 has a new mode for installing Reporting Services known as Native Mode Installation.  This mode offers many benefits including simplified deployment and a reduced surface area for security.  It does this by not requiring the use of Internet Information Services (IIS) to gain access to ASP.NET functionality, the Report Manager application, or the Report Server Web service endpoint.  Reporting Services now does the work of hosting ASP.NET and the .NET Framework as well as leverages the capabilities of HTTP.SYS within the operating system.

So no more IIS!  But wait?  Doesn’t IIS offer other capabilities?

Yes, it does!  One of the most needed features of IIS is HTTP Compression.  This feature is tied directly to IIS and not HTTP.sys. This feature is critical to web farms where network performance is a concern.  This is especially true with Reporting Services installations.  So what can one do to mitigate this issue?

The recommended solution is always the one that is “in-the-box”.  This means installing SQL Server Reporting Services and then configuring it to run within IIS.  Unfortunately this means giving up the simple installation and deployment and increasing the surface area for attack.  So what can one do?

Enter the Wicked HTTP Compression Module!

Reporting Services runs within the ASP.NET pipeline.  It is possible to add support for HTTP compression using an extensibility point of ASP.NET known as an Http Module.  In fact, there are plenty of Http Modules available that implement HTTP compression.  One of them is the Wicked HTTP Compression Module.  I wrote this module years ago and have been enhancing it ever since.  I have just recently updated to support AJAX, .NET Framework 4.0, and more.  Here I will show you how you can change your configuration in SQL Server Reporting Services to use this module and get back compression.

Step 1 – Download and Deploy The Wicked HTTP Compression Module Binary

I now support binary releases of the Wicked HTTP Compression Module.  Download the latest Wicked Http Compression Module for .NET Framework 2.0 from CodePlex at http://httpcompression.codeplex.com/.  Unzip the file and copy it over to the C:\Program Files\Microsoft SQL Server\MSRS10_50.MSSQLSERVER\Reporting Services\ReportManager\Bin directory.

Step 2 – Locate Web.Config for Reporting Services

There are many configuration files for Reporting Services.  On my installation of SQL Server 2008 R2 x64 it was located under the following directory C:\Program Files\Microsoft SQL Server\MSRS10_50.MSSQLSERVER\Reporting Services\ReportManager.

Step 3 – Modify Web.Config

We will now modify the Report Manager web.config file.  IMPORTANT!  Make a backup of this file before you modify it.

Step 3a – Add a new entry to the configSections section.

This will tell ASP.NET that there is a new configuration section that we will be adding to the web.config file.  The Wicked HTTP Compression Module has its own configuration section that we will be adding later on.

<configSections>
 <section name="wickedHttpCompressionModule" type="WickedProgrammer.WickedHttpCompressionSection, WickedCompressionModule, Version=4.0.0.0, Culture=neutral, PublicKeyToken=fdd99273a6f0cac9"/>
 <section name="MicrosoftWebControls" type="System.Configuration.NameValueSectionHandler, System, Version=2.0.3600.0, Culture=neutral, PublicKeyToken=b77a5c561934e089, processorArchitecture=MSIL" />
 <section name="UIConfig" type="Microsoft.ReportingServices.UI.UIConfigSectionHandler,ReportingServicesWebUserInterface" />
</configSections>

Step 3b – Add an entry to the <httpHandlers> section.

The Wicked HTTP Compression Module comes with a tracing capability that give diagnostics on which files got compressed.  To access this diagnostic, you need to first add this entry to the <httpHandlers> section and then enable tracing in the <wickedHttpCompressionModule> config section.  Once done, you can access the trace through the following URL:  http://localhost/Reports/WickedTrace.axd.  If needed, change the server name from localhost to your server name.

<httpHandlers>
 <add verb="*" path="Reserved.ReportViewerWebControl.axd" type="Microsoft.Reporting.WebForms.HttpHandler, ReportingServicesWebUserInterface, Version=10.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" />
 <add verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" validate="false" />
 <add verb="GET" path="WickedCompress.axd" type="WickedProgrammer.WickedHttpCompressionTraceHandler, WickedCompressionModule, Version=4.0.0.0, Culture=neutral, PublicKeyToken=fdd99273a6f0cac9"
 validate="false"/>
</httpHandlers>

Step 3c – Add an entry to the <httpModules> section.

This will tell ASP.NET to load the Wicked HTTP Compression Module into its pipeline.

<httpModules>
 <clear />
 <add name="OutputCache" type="System.Web.Caching.OutputCacheModule" />
 <add name="WickedCompression" type="WickedProgrammer.WickedHttpCompressionModule, WickedCompressionModule, Version=4.0.0.0, Culture=neutral, PublicKeyToken=fdd99273a6f0cac9"/>
 <add name="WindowsAuthentication" type="System.Web.Security.WindowsAuthenticationModule" />

 ...

 <add name="ErrorHandlerModule" type="System.Web.Mobile.ErrorHandlerModule, System.Web.Mobile, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
</httpModules>

Step 3d – Add the <wickedHttpCompressionModule> section to your web.config file.

This is a required step and must be added to your config file.  There are several features enabled in this config file example.  First, take notice that tracing is enabled by setting enableTrace=’true’.  Second, there is an excluded path specified for images.  Third, there is a set of excluded MIME types.  While I have done some configuration, I suspect that more will be needed.  More specifically, additional MIME types will most likely need to be added.  The <excludedMimeTypes> allows one to filter out any MIME types that should not be compressed.  One example of this is the new Word 2007 (.docx) and Excel 2007 (.xlsx) file formats.  These file formats are already compressed and should be excluded if you are downloading these types of files.

<wickedHttpCompressionModule enableTrace="true">
 <excludedPaths>
 <!-- Example:
 Do not compress these pages.
 <add value="/nocompress.aspx" />
 <add value="/image/dynamic.aspx" />
 
 Do not compress these paths and their subdirectories.
 <add value="/images/" />
 <add value="/files/images/" />

 NOTE: The path feature assumes that all subdirectories are included.
 -->
 </excludedPaths>
 <excludedMimeTypes>
 <!-- The following MIME types are already excluded by the WickedHttpCompressionModule.
 JPEG Image image/jpeg
 GIF Image image/gif
 PNG Image image/png
 Zip File application/zip, application/x-zip, application/x-zip-compressed
 GZip File application/x-gzip, application/x-gzip-compressed
 Compressed File application/x-compress, application/x-compressed
 -->
 <add value="application/octet-stream"/>
 <add value="application/pdf"/>
 </excludedMimeTypes>
</wickedHttpCompressionModule>

Step 4 – Modify rsmgrpolicy.config

Reporting Services has its own policy files.  We need to modify the policy file to allow the WIcked HTTP Compression Module to execute.  In this situation, we put a new code group right after the Microsoft_Strong_Name code group.

<CodeGroup
 class="UnionCodeGroup"
 version="1"
 PermissionSetName="FullTrust"
 Name="Microsoft_Strong_Name"
 Description="This code group grants code signed with the Microsoft strong name full trust. ">
 <IMembershipCondition
 class="StrongNameMembershipCondition"
 version="1"
 PublicKeyBlob="002400000480000094000000060200000024000052534131000400000100010007D1FA57C4AED9F0A32E84AA0FAEFD0DE9E8FD6AEC8F87FB03766C834C99921EB23BE79AD9D5DCC1DD9AD236132102900B723CF980957FC4E177108FC607774F29E8320E92EA05ECE4E821C0A5EFE8F1645C4C0C93C1AB99285D622CAA652C1DFAD63D745D6F2DE5F17E5EAF0FC4963D261C8A12436518206DC093344D5AD293"
 />
</CodeGroup>
<CodeGroup class="UnionCodeGroup"
 version="1"
 PermissionSetName="FullTrust"
 Name="WickedHttpModuleCodeGroup"
 Description="Code group for Wicked HTTP module">
 <IMembershipCondition class="UrlMembershipCondition"
 version="1"
 Url="C:\Program Files\Microsoft SQL Server\MSRS10_50.MSSQLSERVER\Reporting Services\ReportManager\bin\WickedCompressionModule.dll" />
</CodeGroup>

Step 5 – Stop and Start Reporting Services using the Reporting Services Configuration Manager

Almost Done!  Now all that is needed is to stop and start Reporting Services using the Reporting Services Configuration Manager.