best practice disconnecting connection inside a package

[m-muecke]

I've got a (singleton) connection setup inside a package with the following:

the <- new.env(parent = emptyenv())

db_conn <- function() {
  if (exists("con", the) && DBI::dbIsValid(the$con)) {
    return(the$con)
  }
  the$con <- DBI::dbConnect(...)
  the$con
}

I've tried using reg.finalizer to disconnect the connection, but I'm not sure if it does what I expect. Is there a best practice for this pattern?

the <- new.env(parent = emptyenv())

db_conn <- function() {
  if (exists("con", the) && DBI::dbIsValid(the$con)) {
    return(the$con)
  }
  the$con <- DBI::dbConnect(...)
  reg.finalizer(
    the,
    \(env) if (DBI::dbIsValid(env$con)) DBI::dbDisconnect(env$con),
    onexit = TRUE
  )
  the$con
}