add ada_get_domain

[schochastics]

kindly requested by webtrack team:

ada_get_domain("https://subsub.sub.domain.co.uk")
#> domain.co.uk

Just glueing some existing functions

[chainsawriot]

Basically this: https://raw.githubusercontent.com/publicsuffix/list/master/tests/tests.txt

[schochastics]

is there a get_domain hidden somewhere in ada-url? Havent found anything.
I am here now but it does not catch all special cases

R_ada_get_domain <- function(url) {
    host <- ada_get_hostname(url)
    ps <- public_suffix(url)
    pat <- paste0("\\.", ps, "$")
    dom <- mapply(function(x, y) sub(x, "", y), pat, host, USE.NAMES = FALSE)
    domain <- paste0(sub(".*\\.([^\\.]+)$", "\\1", dom), ".", ps)
    domain[host == ps] <- ""
    domain[is.na(ps)] <- host
}

#' @rdname ada_get_domain
#' @export
ada_get_domain <- function(url, decode = TRUE) {
    .get(url, decode, R_ada_get_domain)
}

[chainsawriot]

No, I don't think ada has it, given the fact it is not psl aware. It should be the TLD (via psl) plus the thing before it. How about using pat plus all non-dot before it.

domain <- "https://www.domain.biz"
stringr::str_extract(domain, paste0("[^\\.]+\\.", public_suffix(domain)))

[schochastics]

I think this does not work e.g. with the example in #44

[chainsawriot]

Very bad way to fix this (given "kobe.jp" can be extracted).

quickfixquicksand <- function(url, suffix = adaR::public_suffix(url)) {
    hostname <- adaR::ada_get_hostname(url)
    if (suffix == hostname) {
        return(hostname)
    }
    stringr::str_extract(hostname, paste0("[^\\.]+\\.", suffix))
}

quickfixquicksand("https://kobe.jp", "kobe.jp")
quickfixquicksand("https://www.bbc.co.uk")
quickfixquicksand("https://www.bmbf.de")

[schochastics]

there are yet again special treatment for wildcard ps.

R_ada_get_domain <- function(url) {
    host <- ada_get_hostname(url)
    host <- sub("^www\\.", "", host)
    ps <- public_suffix(url)
    pat <- paste0("\\.", ps, "$")

    dom <- mapply(function(x, y) sub(x, "", y), pat, host, USE.NAMES = FALSE)
    domain <- paste0(sub(".*\\.([^\\.]+)$", "\\1", dom), ".", ps)
    domain[host == ps & !ps %in% psl$wildcard] <- ""
    domain[host == ps & ps %in% psl$wildcard] <- ps
    domain[is.na(ps)] <- host
    domain
}

This works for the tests I made, but will now go through the whole list you posted

[schochastics]

oh crap this broke things again

[schochastics]

ok we cannot support all the test cases, because not all test cases have a valid public suffix