R/aaa.R

In socdataR/natality: User Friendly Access to CDC Wonder API

#' Convert List to XML
#'
#' Can convert list or other object to an xml object using xmlNode
#' Copied from: https://github.com/hrbrmstr/wondr/blob/master/R/aaa.r
#' added namespacing
#'
#' @title List to XML
#' @param item list
#' @param tag xml tag
#' @return xmlNode
#' @noRd
#' @author David LeBauer, Carl Davidson, Rob Kooper
list_to_xml <- function(item, tag) {
    # just a textnode, or empty node with attributes
    if(typeof(item) != 'list') {
        if (length(item) > 1) {
            xml <- XML::xmlNode(tag)
            for (name in names(item)) {
                XML::xmlAttrs(xml)[[name]] <- item[[name]]
            }
            return(xml)
        } else {
            return(XML::xmlNode(tag, item))
        }
    }

    # create the node
    if (identical(names(item), c("text", ".attrs"))) {
        # special case a node with text and attributes
        xml <- XML::xmlNode(tag, item[['text']])
    } else {
        # node with child nodes
        xml <- XML::xmlNode(tag)
        for(i in 1:length(item)) {
            if (names(item)[i] != ".attrs") {
                xml <- XML::append.xmlNode(xml, list_to_xml(item[[i]], names(item)[i]))
            }
        }
    }

    # add attributes to node
    attrs <- item[['.attrs']]
    for (name in names(attrs)) {
        XML::xmlAttrs(xml)[[name]] <- attrs[[name]]
    }
    return(xml)
}