Expat Nuget Package

This project builds a Expat Nuget package with static Expat libraries and header files for the x64 platform, built with Visual C++ 2022, against Debug/Release MT/DLL MSVC CRT.

Visit Expat website for additional information about the Expat project and library documentation:

https://github.com/libexpat/libexpat

Package Configuration

The Expat static libraries from this package will appear within the installation target project after the package is installed. The solution may need to be reloaded to make libraries visible. Both, debug and release libraries will be listed in the project, but only the one appropriate for the currently selected configuration will be included in the build. These libraries may be moved into solution folders after the installation (e.g. lib/Debug and lib/Release).

Note that the Expat library path in this package will be selected as Debug or Release based on whether the selected configuration is designated as a development or as a release configuration via the standard Visual Studio property called UseDebugLibraries. Additional configurations copied from the standard ones will inherit this property.

Do not install this package if your projects use debug configurations without UseDebugLibraries. Note that CMake-generated Visual Studio projects will not emit this property.

Expat libraries in this package are built with narrow character support only and cannot parse XML documents maintained as wide character strings.

See StoneSteps.Expat.VS2022.Static.props and StoneSteps.Expat.VS2022.Static.targets for specific package configuration details and file locations.

Building a Nuget Package

This project can build a Nuget package for Expat either locally or via a GitHub workflow. In each case, following steps are taken.

• Expat source archive is downloaded from Expat's website and its SHA-256 signature is verified.

• VS2022 Community Edition is used to build Expat libraries locally and Enterprise Edition to build libraries on GitHub.

• Build artifacts for all platforms and configurations are collected in staging directories under nuget/build/native/lib.

• nuget.exe is used to package staged files with the first three version components used as a Expat version and the last version component used as a package revision. See Package Version section for more details.

• The Nuget package built on GitHub is uploaded to nuget.org. The package built locally is saved in the root project directory.

Package Version

Package Revision

Nuget packages lack package revision and in order to repackage the same upstream software version, such as Expat v2.5.0, the 4th component of the Nuget version is used to track the Nuget package revision.

Nuget package revision is injected outside of the Nuget package configuration, during the package build process, and is not present in the package specification file.

Specifically, nuget.exe is invoked with -Version=0.6.24.123 to build a package with the revision 123.

Version Locations

Expat version is located in a few places in this repository and needs to be changed in all of them for a new version of Expat.

• nuget/StoneSteps.Expat.VS2022.Static.nuspec (version)
• devops/make-package.bat (PKG_VER, PKG_REV, EXPAT_FNAME, EXPAT_RNAME, EXPAT_SHA256)
• .github/workflows/build-nuget-package.yml (name, PKG_VER, PKG_REV, EXPAT_FNAME, EXPAT_RNAME, EXPAT_SHA256)

EXPAT_SHA256 ia a SHA-256 checksum of the Expat package file and needs to be changed when a new version of Expat is released.

In the GitHub workflow YAML, PKG_REV must be reset to 1 (one) every time Expat version is changed. The workflow file must be renamed with the new version in the name. This is necessary because GitHub maintains build numbers per workflow file name.

For local builds package revision is supplied on the command line and should be specified as 1 (one) for a new version of Expat.

GitHub Build Number

Build number within the GitHub workflow YAML is maintained in an unconventional way because of the lack of build maturity management between GitHub and Nuget.

For example, using build management systems, such as Artifactory, every build would generate a Nuget package with the same version and package revision for the upcoming release and build numbers would be tracked within the build management system. A build that was successfully tested would be promoted to the production Nuget repository without generating a new build.

Without a build management system, the GitHub workflow in this repository uses the pre-release version as a surrogate build number for builds that do not publish packages to nuget.org, so these builds can be downloaded and tested before the final build is made and published to nuget.org. This approach is not recommended for robust production environments because even though the final published package is built from the exact same source, the build process may still potentially introduce some unknowns into the final package (e.g. build VM was updated).

Building Package Locally

You can build a Nuget package locally with make-package.bat located in devops. This script expects VS2022 Community Edition installed in the default location. If you have other edition of Visual Studio, edit the file to use the correct path to the vcvarsall.bat file.

Run make-package.bat from the repository root directory with a package revision as the first argument. There is no provision to manage build numbers from the command line and other tools should be used for this (e.g. Artifactory).

Sample Application

A Visual Studio project is included in this repository under sample-expat to test the Nuget package built by this project. This application prints elements and their attributes of a hard-coded XML string.

In order to build sample-expat.exe, open Nuget Package manager in the solution and install either the locally-built Nuget package or the one from nuget.org.