programmatically retrieve frozen urls for CRAN from packagemanager.rstudio.com

Posit Professional products Package Management
1

Is there a way via script to retrieve the frozen URL of CRAN repo when given a date? Interactively in rspm's setup page this works but I need to do that via script given a date and maybe more for binary package url.

2

If you want to retrieve packages by date, as opposed to by version number, you can use the MRAN time machine:

options(repos=c(CRAN="https://mran.microsoft.com/snapshot/yyyy-mm-dd"))

Fill in yyyy-mm-dd with the date you're after.

3

Good point Hong,
microsoft's MRAN offers this feature. Still I am wondering whether RSPM also can somehow do it.

4

Take a look at RStudio Package Manager - there you can select any snapshot available there by clicking on any date in the calendar which will lead to an URL like
https://packagemanager.rstudio.com/cran/2021-09-21. Please also make note of the "Lock Package Data" feature.

5

Well Michael,
I need without human action the latest CRAN snapshot identified. Is there any chance to replace clicking on a date by some call to an API or so?

6

You may be aware of the Swagger API but this is currently in 0.0.1-alpha version and by far not able to meet your requirements.

I wonder what is the background for this request, especially why you cannot use /cran/latest ? We definitely can look into getting the necessary API calls exposed to RSPM once we understand the intent etc...

Happy to follow-up offline as well.

7

Hi I would also be interested in getting the url programmatically. I'm creating utils-kind of package in my company and I want to give user flexibility to choose either MRAN or RSPM snapshots as it take ages to compile packages on linux machines... It makes a significant difference in CI/CD pipelines.

8

Hi Michal,

you can programmatically get the link via the RSPM API, e.g.

curl -X 'POST'   'https://packagemanager.rstudio.com/__api__/url'   -H 'accept: application/json'   -H 'Content-Type: application/json'   -d '{
  "locked": false,
  "repo": "cran",
  "snapshot": "2019-05-06T00:00:00.000Z"
}' | jq

The above will retrieve the snapshot URL for 2019-05-06 in the resulting json file under "example".

IMPORTANT:

  • The above approach makes use of an unpublished part of the RSPM API (RStudio Package Manager). As a consequence there is no guarantee that this approach will still work in the future and hence is unsupported at the moment.
  • The obtained URL's however will be reproducible as per their respective setting.