ubuntu-dailies.R

#!/usr/bin/env Rscript
library(rvest)
futile.logger::flog.info('starting...')
futile.logger::flog.info('checking website')

ubuntu_dailies <- read_html("https://dailies.rstudio.com/rstudioserver/oss/ubuntu/amd64/")
futile.logger::flog.info('extracting url')
ubuntu_latest <- ubuntu_dailies %>%
  html_nodes(".filename a") %>%
  html_attr("href")
futile.logger::flog.info(paste0('URL: ', ubuntu_latest[1]))

futile.logger::flog.info('building filename and filepath')
url_split <- unlist(strsplit(ubuntu_latest[1], "/"))
filename <- url_split[length(url_split)]

filepath <- paste0("/tmp/", filename)

futile.logger::flog.info(paste0('downloading file: ', filepath))
download.file(ubuntu_latest[1], filepath, quiet = TRUE)
futile.logger::flog.info('installing')
install_info <- system2("/usr/bin/gdebi", args = c("-n", filepath), stdout = TRUE, stderr = TRUE)
futile.logger::flog.info('getting installed rstudio version')
rstudio_version <- system2("/usr/sbin/rstudio-server", args="version", stdout = TRUE)
futile.logger::flog.info(paste0('removing: ', filepath))
unlink(filepath)

# posting to slack
futile.logger::flog.info("Posting to slack...")
if ( Sys.getenv("SLACK_WEBHOOK_URL")[1] == ""){
	futile.logger::flog.error("SLACK_WEBHOOK_URL environment variable not set")
	quit()
} else {
	slack_webhook_url <- Sys.getenv("SLACK_WEBHOOK_URL")[1]
}
if ( Sys.getenv("RSTUDIO_SERVER_URL")[1] == ""){
	futile.logger::flog.error("RSTUDIO_SERVER_URL environment variable not set")
	quit()
} else {
	rstudio_server_url <- Sys.getenv("RSTUDIO_SERVER_URL")[1]
}
slack_message <- paste0("The RStudio Server updater has run. <", rstudio_server_url, "|Now at v", rstudio_version, "> and the current daily is: ", filename)
payload <- list(text = slack_message , username = "RStudio Server Updater")
r <- httr::POST(slack_webhook_url, body = payload, encode = "json")

# the end
futile.logger::flog.info('finished')

It desperately needs some actual error handling, but this script gets the URL of the latest RStudio Server Daily for ubuntu, downloads it and installs it.

It needs two environment variables setting for the post to slack (via a webhook) thing at the end to work.

SLACK_WEBHOOK_URL - the URL of your slack webhook
RSTUDIO_SERVER_URL - the URL of the RStudio Server instance we're updating (this is used as a link in the message)

You'll need the rvest, futile.logger, and httr R packages installed. You'll also need the 'gdebi' command line tool

I have this set up as a cronjob to update RSS a couple of times a week. I'm running it as root, but i probably shouldn't be. (I could perhaps improve that by running the script as a non-privileged user and doing a 'sudo gdebi...' in the system2 call, but I haven't spent a great deal of time thinking that through).