IIS Compression is a bundle of two IIS compression scheme providers iisbrotli.dll and iiszlib.dll that enable IIS to compress HTTP response contents. iisbrotli.dll supports Brotli compression, while iiszlib.dll supports both Gzip and Deflate compression.
An IIS compression scheme provider is a pluggable extension of IIS StaticCompressionModule and DynamicCompressionModule - essentially a dynamic link library (dll) that implements the compression algorithm and exposes the IIS HTTP Compression API. IIS StaticCompressionModule and DynamicCompressionModule load the registered compression scheme providers into worker process at runtime, and leverage them to perform compression for static files and dynamically-generated contents, respectively.
Download the Microsoft IIS Compression release from the following locations:
The IIS Compression installer registers iisbrotli.dll as the br (Brotli) compression scheme provider in applicationHost.config. It also replaces the default gzip compression scheme provider gzip.dll with iiszlib.dll. A sample httpCompression section in applicationHost.config is shown below:
<httpCompression directory="%SystemDrive%\inetpub\temp\IIS Temporary Compressed Files">
<scheme name="br" dll="%ProgramFiles%\IIS\IIS Compression\iisbrotli.dll" />
<scheme name="gzip" dll="%ProgramFiles%\IIS\IIS Compression\iiszlib.dll" />
<dynamicTypes>
<add mimeType="text/*" enabled="true" />
<add mimeType="message/*" enabled="true" />
<add mimeType="application/x-javascript" enabled="true" />
<add mimeType="application/javascript" enabled="true" />
<add mimeType="*/*" enabled="false" />
</dynamicTypes>
<staticTypes>
<add mimeType="text/*" enabled="true" />
<add mimeType="message/*" enabled="true" />
<add mimeType="application/javascript" enabled="true" />
<add mimeType="application/atom+xml" enabled="true" />
<add mimeType="application/xaml+xml" enabled="true" />
<add mimeType="image/svg+xml" enabled="true" />
<add mimeType="*/*" enabled="false" />
</staticTypes>
</httpCompression>
- Install Visual Studio 2017
- You need to install these components additionally after(or while) installing Desktop development with C++
- Wix Toolset Visual Studio 2017 Extension
- Visual C++ ATL (x86/x64) with Spectre Mitigations
- VC++ 2017 version 15.9 v14.16 latest v141 tools
- Clone this project with submodules.
git clone --recurse-submodules https://github.com/Microsoft/IIS.Compression.git
- Build the code using the
build.cmd(the location of msbuild.exe needs to be added intoPATHenvironment variable).
This project welcomes contributions and suggestions. Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us the rights to use your contribution. For details, visit https://cla.microsoft.com.
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This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.