R/spq_prefix.R

In lvaudor/glitter: glitter makes SPARQL

#' Add prefixes to the query
#' @param .query a list with elements of the query
#' @param prefixes a vector of prefixes
#' @param auto whether to use built-in prefixes
#' @return A query object
#' @export
#' @examples
#' spq_init() %>%
#' spq_prefix(prefixes=c(dbo="http://dbpedia.org/ontology/"))
spq_prefix = function(.query = NULL, auto = TRUE, prefixes = NULL){
  if (!is.null(prefixes)) {auto=FALSE}
  if (!is.data.frame(prefixes) & !is.null(prefixes)) {
    prefixes = tibble::tibble(
      name = names(prefixes),
      url = prefixes,
      type = "user"
    )
  }
  if (auto==TRUE) {
    prefixes_auto = usual_prefixes %>%
      dplyr::filter(.data$name %in% .query[["prefixes_used"]]) %>%
      dplyr::filter(.data$type!="Wikidata")
    prefixes = dplyr::bind_rows(prefixes, prefixes_auto)
  }
  prefixes = prefixes %>%
    dplyr::select(name, url) %>%
    unique()

  .query[["prefixes_provided"]] = dplyr::bind_rows(
    .query[["prefixes_provided"]],
    prefixes
  ) %>%
    unique()

  return(.query)
}

utils::globalVariables("usual_prefixes")