add option to override the cloud CRAN mirror for installing dependencies

[daroczig]

This adds a new CLI option for overriding the CRAN mirror to be used to download dependencies. Let me know what you think.

[eddelbuettel]

My first gut instinct was ... doesn't this come by default via getOption("repos")[["CRAN"]] ? But then I probably don't know remotes::install_github() well enough...

[daroczig]

Oh, sure, @CRAN@ is the default in getOption("repos")[["CRAN"]], but I'd like to override that to eg http://eddelbuettel.github.io/drat -- and I have not found an easy way to do that on the command line without temp setting .Rprofile or similar. NOTE: it definitely can be due to my limited knowledge.

[eddelbuettel]

Would this help? Default for the last few Debian releases.

But I guess we can add the option.

[eddelbuettel]

But I think your current suggested default of @CRAN@ is not a great choice. Why not just use https://cloud.r-project.org ?

[daroczig]

Thanks, I've just updated the default value. But if you don't feel comfortable merging this, no worries, I'll do the .Rprofile update to set my own preferred CRAN mirror before calling installGithub.r.

[eddelbuettel]

And I think the three dots here have special meaning ... which we do not want.

Also, as I have been picking so much, twothree more changes:

• can we renamed it to CRAN rather than DEPREPO ? Shorter, simpler, obvious default
• can you place it behind [-u UPDATE] here and below it below?
• can you add an entry to ChangeLog?

[daroczig]

And I think the three dots here have special meaning ... which we do not want.

Yeah, that looked strange to me as well, but that's how it's being used in install2.r and I thought that's part of your coding style :P So I decided to do this for the sake of consistency. Changing it in a sec.

[eddelbuettel]

Well if locally setting works then we should do that.

What happens now for you with @CRAN@? Does it fail? Does it stop and ask (which hardly works for littler) ? I am not that opposed to merging. Just want to understand, and keep it simple...

[daroczig]

What happens now for you with @cran@? Does it fail? Does it stop and ask (which hardly works for littler) ?

Sure, I've tested before submitting the PR both with @CRAN@ and the CDN mirror and both worked on the command line without trying that interactive menu.

Will do the above changes later today, thanks! I'm not sure regarding the deprepo -> CRAN rename thought, as it could be something else too, eg a drat repo and it's called repos in install.packages and install2.r as well.

[eddelbuettel]

Yes, but we use REPOS here for the git repo ... Hm.

[eddelbuettel]

So maybe the simpler fix is to have a new variable cranrepo, that by is by getOption() with a default / fallback of the CDN ? The it should be set by default, is overrideable and we don;t clutter things with a new argument. Or I just merge -- let's not overcomplicate...

[daroczig]

I'm happy to update the PR as per your suggestion to have options as a default so that folks could rely on that as well -- actually, I was originally thinking about copying over https://github.com/eddelbuettel/littler/blob/master/inst/examples/install2.r#L52 to installGithub.r as well, but then decided that it might overcomplicate things :)

For the sake of consistency, I'd rather keep the option name as repos (as the very same folks are using install2.r and installGithub.r so they do not have to set two separate options for the same stuff), same for the -r CLI option.

The REPOS that stands for the GH repos can be actually renamed to anything else ... without affecting users in any way, so I think that's fine. Actually, I was thinking originally renaming that to GHREPOS :) But did not want to introduce a lot of change here.

Let me push a commit on what I have in mind based on the above and then pls let me know what you think.

[daroczig]

Okay, this is definitely more updates than I originally planned, sorry for that, but I hope looks good.

[eddelbuettel]

Changing install2.r was not part of the plan.

[eddelbuettel]

But I guess on the upside we can now set multiple repos on the command-line....

[daroczig]

Changing install2.r was not part of the plan.

Oh, sorry again, I thought it's better to do these small and non-breaking changes there for the sake of consistency.

But I guess on the upside we can now set multiple repos on the command-line....

I think that was already the case -- it was just not documented and it threw a warning (on comparing multiple values with "NULL") when someone set multiple repos (but worked).

[eddelbuettel]

All good -- should be a useful extension. Especially being able to add something like drat on the fly.

Thanks for working on this!