curl handles in handle_pool become dead in package finalizer

[okhoma]

When same urls are requested in some package functions and in package finalizer, curl handles cached in handle_pool become "dead", because curl handle finalizers are run before package finalizer.

Here is a reprex (put in a package)

test <- function() httr::GET("https://www.google.com")
.onLoad <- function(x, y) {
  reg.finalizer(environment(sys.function()), function(env) test(), TRUE)
  test()
}

Right now I just call httr::handle_reset() for each URL used in the finalizer, but I would prefer to have a more generic approach, because these URLs are called by some other packages internals and they may change in the future, breaking my package.

I think one of the following options could work:

• have an option to not maintain handle_pool at all
• have a function handle_pool_reset() to clear the whole pool
• update httr::handle_find() to check if the handle is not dead before returning it (will require new curl::handle_is_dead() function)
• update httr::handle_find() to add its own finalizer that would remove the url from the pool before the handle is cleared by curl

I can submit a pool request :), just not sure which approach would be preferred.

Thanks, Oleh Khoma