R/read_ecco.R

In COMHIS/estc: English Short Title Catalogue (ESTC) Metadata Toolkit

#' @title Read ECCO
#' @description Read ECCO data dump.
#' @param version Version number 1: ECCOI; 2: ECCOII
#' @return ECCO data.frame
#' @export
#' @details Assumes that the working directory includes the source data file.
#' @author Leo Lahti \email{leo.lahti@@iki.fi}
#' @references See citation("estc")
#' @examples \dontrun{ecco <- read_ecco(version = 2)}
#' @keywords utilities
read_ecco <- function (version = 2) {

  # ECCOI	  
  if (version == 1) {
  
    f <- "ecco.csv.gz"
    message(paste("Reading file", f))
    ecco <- read.csv(f) # Old dump CSV
  
  } else if (version == 2) {

    f <- "ecco2.json.gz"
    message(paste("Reading file", f))

    ecco <- fromJSON(file = f, method = "C")
    # Ignore column 11 "containsGraphicOfType" which is hierarchical    
    ecco <- as.data.frame(t(sapply(ecco, function (x) {x[setdiff(names(x), "containsGraphicOfType")]})), stringsAsFactors = FALSE)
    ecco <- as.data.frame(sapply(ecco, function (x) {unlist(x)}))

  }

  # Polish ecco ID
  ecco$id <- as.character(ecco$ESTCID)
  ecco$documentID <- as.character(ecco$documentID)
  ecco$ESTCID <- as.character(ecco$ESTCID)
  ecco$totalPages <- as.numeric(as.character(ecco$totalPages))
  # Remove leading zeroes (T012345 -> T12345)
  ecco$id <- sapply(ecco$id, function (x) {paste(substr(x, 1, 1), gsub("^0+", "", substr(x, 2, nchar(x))), sep = "")}, USE.NAMES = FALSE)

  message("ECCO read successfully.")

  ecco 
}