How to access zip_url of master branch from site.github metadata?

When a Github page is created in gh-pages branch I can have a download link to the zip/tar of the gh-pages branch, with site.github.zip_url. But I want a link to the master branch rather than the gh-pages branch. Besides writing down the url explicitly, is there anyway to access it from the site.github metadata?

As far as I know, that information isn’t available in the site.github Jekyll metadata. It’s pretty easy to calculate though, given the URL of the repository itself. If the URL of the GitHub repository is https://github.com/Octocat/Spoon-Knife, then the Zip URL for the master branch is https://github.com/Octocat/Spoon-Knife/archive/master.zip

I hope that helps!