Buildpack auto-installs 'Suggests' dependencies about r-buildpack

[cf-gitbot]

We have created an issue in Pivotal Tracker to manage this:

https://www.pivotaltracker.com/story/show/175574306

The labels on this github issue will be updated when the story is started.

[ForestEckhardt]

This is an interesting idea. I will have to investigate whether or not doing this breaks any of our current functionality. Let me run a round of tests and get back to you!

[chrismasonthom-co]

That's great, thanks Forest. You'll have seen I've made a fork with this change in the interim - it's currently working for me, but definitely run some wider tests!

[elinork]

I've been struggling with staging timeouts, so I'd appreciate this, too, so we could start avoiding unnecessary dependencies.

[hedberg503]

I would also appreciate this, as I am also struggling with staging timeouts. Specifically with the sf package as a suggested dependency for ggplot2.

[menehune23]

Hi @chrismasonthom-co, thanks for the thorough post and suggestions. We're maintaining a lot of buildpacks these days, and our focus has also shifted quite a bit to the Paketo buildpacks that are more container-centric, so we haven't been able to prioritize a fix for this.

That said, if you'd be willing to PR something into this CF buildpack based on your fork, we'd be happy to take a look. If there's a way to make this opt-in (e.g. via an env var to override current behavior) to lower risk of backwards incompatibilities, that would be optimal.

[ryanmoran]

For this implementation, I could imagine an API in the existing r.yml file that looks something like the following:

---
cran_mirror: https://cran.r-project.org
dependencies:
- Depends
- Imports
packages:
- name: stringr

Where dependencies is expected to be an array with any of the allowed values: "Depends", "Imports", "LinkingTo", "Suggests", or "Enhances".

This would then create a dependencies option in the install.packages command like the following:

install.packages(... dependencies=c("Depends", "Imports") ...)

If the field is missing or empty, then we can assume the dependencies option should take on its existing behavior which is to be set to TRUE like the following:

install.packages(... dependencies=TRUE ...)

[menehune23]

Closing as stale. @chrismasonthom-co feel free to reopen if necessary