R/wget.R

In wget: Setting Download Method to 'wget'

##' set "download.file.method" to "wget" and "download.file.extra" to "-c"
##'
##' setting download method to "wget -c", so that it can continue the download from where it left off.
##' @title wget_set
##' @param method download method (wget, default)
##' @param extra extra parameter (-c, default)
##' @return No return value, called for side effects
##' @export
##' @examples
##' wget_set()
##' @author Guangchuang Yu
wget_set <- function(method = "wget", extra = "-c") {
    exit_code <- setup_wget()
    if (exit_code != 0) {
        return()
    }

    get_download_setting()
    options(download.file.method = method)
    options(download.file.extra = extra)
}


##' unset download method setting by `wget_set`
##'
##' set the download method and extra parameter back to what it is or NULL if it is not specify
##' @title wget_unset
##' @return No return value, called for side effects
##' @importFrom yulab.utils get_cache_element
##' @export
##' @examples
##' wget_unset()
##' @author Guangchuang Yu
wget_unset <- function() {
    wget_set(
        method = get_cache_element("wget", "download.file.method"), 
        extra = get_cache_element("wget", "download.file.extra")
    )
}

#' @importFrom yulab.utils update_cache_item
get_download_setting <- function() {
    update_cache_item(
        item = "wget", 
        elements = list(
            download.file.method = getOption('download.file.method'),
            download.file.extra = getOption('download.file.extra')
        )
    )
}

#' @importFrom yulab.utils user_dir
setup_wget <- function() {
    # exit code: 
    # 0 for success
    # 1 for fail

    has_wget <- yulab.utils:::has_bin("wget")

    if (has_wget) return(0)

    os <- yulab.utils:::which_os()
    if (os != "Windows") {
        # we assume `wget` is installed in MacOS and Linux
        message("Please install wget manually")
        return(1)
    }

    if (!interactive()) return(1)
    
    message("wget is not found. Download it?\n")
    if (utils::menu(c("Yes", "No")) != 1) {
        return(1)
    } 
    
    dir <- user_dir("wget", appauthor="YuLab")
    destfile <- file.path(dir, "wget.exe") 
    
    if (!file.exists(destfile)) {
        url <- "https://eternallybored.org/misc/wget"
        # current latest version, access date: 2024-08-17 
        version <- "1.21.4" 

        arch <- 32
        if (.Platform$r_arch == "x64") {
            arch <- 64
        } 
        
        url2 <- sprintf("%s/%s/%s/wget.exe", url, version, arch)
        yulab.utils:::mydownload(url2, destfile)
    }

    PATH <- Sys.getenv('path')
    Sys.setenv(path = sprintf("%s;%s", destfile, PATH))
    return(0)
}