[WIP] Set up docs to release from Appveyor CI

[amyrlam]

Resolves part of: #5238

• Turn on Appveyor for .md file changes
• WIP: Add Appveyor continuous deployment
  See:
  • https://help.appveyor.com/discussions/questions/2894-pushing-to-gh-pages
  • https://docusaurus.io/docs/en/publishing#automating-deployments-using-continuous-integration

[gaearon]

AppVeyor has been very flaky for us and we've been thinking about moving to Azure.
Can we release from Travis instead?

[iansu]

Travis has Windows support now. I was considering making a PR to try it out. Is that something we want to consider? There are definitely pros and cons to having a single CI service.

[gaearon]

If we can make it work sure.

[iansu]

Okay, I'll give it a try and we'll see what happens. Windows support on Travis is still in beta/preview but some other projects seem to be using it successfully.

[severen]

Here's a couple issues I ran into when I set it up for a project last week:

• The build will hang and never start if you have a secure environment variable configured.
• The build will hang and never complete if you have the Yarn installer (that is automatically run for a repo with a yarn.lock) check GPG signatures, which it does by default (YARN_GPG=no to disable). I believe in this case the build never completes because it doesn't close the gpg-agent daemon.

Just thought I'd drop this here to hopefully help you avoid headaches. Apart from that it's been working well for me.

[amyrlam]

Close in favor of using Travis on #5547, PR in progress

[iansu]

#5547 is just for setting up Windows on Travis. There are some bugs on Travis blocking that PR so I don't think we should combine these two things.

[amyrlam]

@iansu ok. Can I work on the continuous deployment on Travis instead, or is that not possible at this point? (I'm a bit confused by the Travis / Appveyor dual setup, but will dig into it more.)

[iansu]

Yes, feel free to work on it. Just ignore Appveyor for now. If you get stuck make a PR and we can help you with it.