Vanity URL for Go mod with zero infrastructure

13 Nov 2020 · Two minute read · on Gianluca's blog

This post is about how I renamed a go module from github.com/something/somethingelse to go.gianarb.it/somethingelse. It requires zero infrastructure, just a static site that can run on GitHub.

I used one of the many projects I have that nobody cares about gianarb/go-irc.

Why

You know, is one of those ideas you have in your mind for ages, but who cares? At least for me that I don’t have any cool open source project under my name.

I am not one of those people who suffer when realizing that it is not escale. If you end up having a project that gets traction and is tight to github.com because you didn’t think about another way to go, you are stuck. And even if GitHub today is cool, it won’t stay cool forever.

Filippo Valsorda @FiloSottile today tweeted about this topic, and I looked at how he set up filippo.io/age to solve this little dilemma.

Goals

This is not about how to escape from GitHub but is about setting up a “vanity URL” that won’t lock you or your project to GitHub. It does not require any infrastructure, just a domain that you can point to a GitHub Pages.

Prerequisite

  1. Create a DNS record that points as CNAME to <github-handle>.github.io. I used go.gianarb.it
  2. Create a repository; it will be the home for your static site. Mine is gianarb/go-libraries
  3. Set the repository up to be a GitHub page and enable HTTPS. You can enable it via the repository Settings; we will push HTML files to it directly, so I used the master branch as the GitHub page’s source.

Add your first library.

If your library is already using go mod, you have to change the module name to the new one. In my case, from was github.com/gianarb/go-irc to go.gianarb.it/irc. I just searched and replaced with my editor in all the project. Renaming a module is a bc break; I am not sure how to avoid or mitigate that; if you know, let me know!

You can push a new file to your static site repository; I called my irc:

<html>
    <head>
        <meta name="go-import" content="go.gianarb.it/irc git https://github.com/gianarb/go-irc">
        <meta http-equiv="refresh" content="0;URL='https://github.com/gianarb/go-irc'">
    </head>
    <body>
        Redirecting you to the <a href="https://github.com/gianarb/go-irc">project page</a>...
    </body>
</html>

Replace your URL accordingly, but as soon as you push this file and GitHub will release it to your page, you will be able to import: go.gianarb.it/irc.

Conclusion

This methods works as a safeguard if you decide to move your code out from GitHub. The static site can be deployed to Netlify, S3 or served by Nginx. It does not need to stay on GitHub.

Same for your code, if you decide to move from GitHub to GitLab you can do it transparently.

Something weird with this website? Let me know.