How to submit an R package to CRAN via GitHub Actions?

Question

I've created an R package and I'd like to upload it to CRAN via GitHub Actions whenever I merge changes into the master branch. I've found a lot of examples of R actions and I've even looked up how some of the most popular packages like dplyr do it and even though I've found a devtools::release() helper function, I still haven't seen a workflow that would submit a library to CRAN when you merge changes into the master branch. Do package developers do this manually? Is there any reason why this hasn't been automated?

Answer 1

CRAN works quite differently from other language repositories, as uploads are not fully automated like in e.g. PyPI.

When you upload a new package, it is subject to verification from an actual human. When you update a package, if it triggers certain checks it will also be subject to a new review from a human. When a package uploads successfully and passes the first verification, many automated checks are run for it over the course of weeks (e.g. different OSes, compilers, compiler options, architectures, sanitizers, valgrind, etc.), and precompiled binaries are automatically generated for some platforms and R versions from your source code.

The CRAN policies explicitly state that frequent updates are not allowed, and you're not supposed to be submitting uploads any faster than once every couple months, for which I think this level of automation would not be worth it.

Even if you do want to automate this process, there is an email verification in the middle, so you'd perhaps have to do something with selenium + other scripts.

BTW if you are worried about complicated building processes and are using RStudio, you can configure on a per-project basis what arguments to use when building source or binary distributions of your package.