[v2] Deploying to GitHub pages removes custom domain from repository settings

[Alex1304]

🐛 Bug Report

If you deploy to GitHub pages with a custom domain, the custom domain will be removed from the repository settings and you need to re-add it after every deploy.

Have you read the Contributing Guidelines on issues?

Yes I did.

To Reproduce

1. In your GitHub repository settings,
   configure a custom domain for GitHub pages
2. In docusaurus.config.js, set url to your custom domain, with / as baseUrl
3. Follow the Deployment guide for GitHub pages
4. Run yarn deploy

Expected behavior

It should deploy the site at the custom domain and not modify the repository settings

Actual Behavior

It deploys the site at the default github.io domain, if you go back to the GitHub repository settings you can notice the custom domain was removed, you need to manually re-add it.

Your Environment

Docusaurus v2.0.0-alpha.70

Reproducible Demo

https://github.com/Alex1304/botrino

[slorber]

It should deploy the site at the custom domain and not modify the repository settings

I don't understand what you mean by "not modify the repository settings".

I don't see a static/CNAME file on your site's repo, this is required afaik for GH pages custom domains, as documented.

If you feel like we could document this better, don't hesitate to submit a PR please

[Alex1304]

Indeed I somehow completely missed this information regarding the CNAME file, not sure how it happened. The issue I'm experiencing is actually documented here https://docs.github.com/en/free-pro-team@latest/github/working-with-github-pages/troubleshooting-custom-domains-and-github-pages#cname-errors

If you feel like we could document this better, don't hesitate to submit a PR please

I don't know if it would be relevant to highlight this section in a :::info box or something like that, if so I don't mind attempting a PR for it.

[slorber]

yes using an :::info box could be helpful, please send a doc PR :)

[greenpau]

I am running into this issue too. The repo is here: https://github.com/authcrunch/authcrunch.github.io

I have CNAME files in all branches, including gh-pages. However, once I deploy, the custom domain setting in "Settings", "Pages" gets cleared.

What is the fix?

[slorber]

@greenpau how is this the same issue. The op above forgot to create a static/CNAME, and once they did the issue was fixed.

If you have an issue despite having a CNAME file then it's a different problem.

And in practice I do see your custom domain not being "cleared": https://docs.authcrunch.com/

[greenpau]

I fixed the issue by adding “static/CNAME” file. Previously, I only had CNAME at the root of the directory tree.