R/zzz.R

In rplos: Interface to the Search API for 'PLoS' Journals

pbase <- function() 'http://api.plos.org/search'

#' Concatenate author names, if present, used in other functions.
#'
#' @param x a single list element with PLoS API returned nested elements
#' @return data.frame of results, with authors concatenated to single vector.
#' @export
#' @keywords internal
concat_todf <- function(x){
	if(inherits(x$author_display, "character")){
	  if(length(x$author_display) > 1){
	    x$author_display<-paste(x$author_display, collapse=", ")
	  } else
		{x$author_display<-x$author_display}
		data.frame(x)
	} else
		if(inherits(x$author, "character")){
			if(length(x$author) > 1){x$author<-paste(x$author, collapse=", ")} else
			{x$author<-x$author}
			data.frame(x)
		} else
	data.frame(x)
}

#' Adds elements in a list that are missing because they were not returned
#' in the PLoS API call.
#'
#' @param x A list with PLoS API returned nested elements
#' @return A list with the missing element added with an
#' 		"na", if it is missing.
#' @export
#' @keywords internal
addmissing <- function(x){
	names_ <- names(x[[which.max(lapply(x, length))]])

	bbb <- function(x){
		if(identical(names_[!names_ %in% names(x)], character(0))){x} else
		{
			xx <- rep("na", length(names_[!names_ %in% names(x)]))
			names(xx) <- names_[!names_ %in% names(x)]
			c(x, xx)
		}
	}
	lapply(x, bbb)
}

#' Function to insert "none" character strings where NULL values found to
#' faciliate combining results
#'
#' @export
#' @keywords internal
insertnones <- function(x) {
	fields = NULL
	f2 <- strsplit(fields, ",")[[1]]
	toadd <- f2[!f2 %in% names(x) ]
	values <- rep("none", length(toadd))
	names(values) <- toadd
	values <- as.list(values)
	x <- c(x, values)
	x
}

ploscompact <- function(l) Filter(Negate(is.null), l)

strextract <- function(str, pattern) regmatches(str, regexpr(pattern, str))
strtrim <- function(str) gsub("^\\s+|\\s+$", "", str)

plos_is_doi <- function(x) {
  grepl("[0-9]+\\.[0-9]+/.+", x)
}

plos_check_dois <- function(x) {
  stopifnot(inherits(x, "list") || inherits(x, "character"))
  x <- vapply(x, utils::URLdecode, "")
  res <- vapply(x, plos_is_doi, logical(1))
  if (all(res)) {
    TRUE
  } else {
    stop("These are probably not DOIs:\n\n", paste0(names(res[!res]), "\n"), call. = FALSE)
  }
}