R/getDownloadLink.R

In rntq472/RBNZ: Download Data from the Reserve Bank of New Zealand Website

##' Determine the URL for a File to be Downloaded
##'
##' Deprecated - the series pages are no longer used.
##'
##' @inheritParams getSeries
##' @param subFileName The name of the file to be downloaded, as provided by
##' seriesOptions(). May contain only part of a series.
##' @param seriesPage An XML document returned by xml2::read_html containing the
##' webpage pertaining to the desired series.
##'
##' @return Character string giving the URL of the file to be downloaded.
##'
##' @author Jasper Watson
##'
##' @keywords internal
##'
##
getDownloadLink <- function(subFileName, seriesPage, series) {

    if (series == "SDDS") {

        xpath <- paste0("//*[contains(@href, '/-/media/ReserveBank/Files/Statistics/sdds/",
                    subFileName,
                    "')]")

    } else {

        xpath <- paste0("//*[contains(@href, '/-/media/ReserveBank/Files/Statistics/tables/",
                        tolower(series),
                        "/",
                        subFileName,
                        ".xlsx')]")

    }

    linkNode <- html_nodes(seriesPage, xpath = xpath)

    if (length(linkNode) < 1) {

        xpath <- paste0("//*[contains(@href, '/-/media/ReserveBank/Files/Statistics/tables/",
                        series,
                        "/",
                        subFileName,
                        ".xlsx')]")

        linkNode <- html_nodes(seriesPage, xpath = xpath)

    }

    if (length(linkNode) < 1) {

        xpath <- paste0("//*[contains(@href, '/-/media/ReserveBank/Files/Statistics/tables/",
                        tolower(series),
                        "/",
                        subFileName,
                        ".XLSX')]")

        linkNode <- html_nodes(seriesPage, xpath = xpath)

    }

    filePath <- html_attr(linkNode, "href")

    url <- file.path("https://www.rbnz.govt.nz", filePath)

    if (length(url) > 1)
        url <- url[[1]]

    url

}