R/reader.R

In vigicaen: 'VigiBase' Pharmacovigilance Database Toolbox

#' Internal arrow reader
#'
#' Used in [tb_vigibase()], [tb_who()]
#'
#' @param file_name Character string
#' @param folder Character string
#'
#' @noRd
#' @examples
#'
#' demo <-data.frame(f0= c("96548661   32194501051119460820"))
#'
#' tmp_folder <- tempdir()
#'
#' path_base <- paste0(tmp_folder, "/reader/")
#'
#' write.table(demo, file = paste0(path_base, "DEMO.txt"),
#'             row.names = FALSE, quote = FALSE, col.names = FALSE)
#'
#' vigicaen:::reader("DEMO.txt", path_base)
#'
#' unlink(path_base, recursive = TRUE)

reader <- function(file_name, folder){
  if (stringr::str_detect(file_name, "csv$")) {
    t1 <- arrow::read_csv_arrow(
      paste0(folder, file_name),
      col_names = FALSE,
      as_data_frame = FALSE
    )
  }

  if (stringr::str_detect(file_name, "txt$")) {
    t1 <- arrow::read_delim_arrow(
      paste0(folder, file_name),
      col_names = FALSE,
      as_data_frame = FALSE,
      delim = "\t",
      schema = arrow::schema(f0 = arrow::utf8())
    )
  }

  return(t1)
}