R/ds_add.R

In bernhard-da/datastore: Creates a datastore which can contain versioned datasets

#' ds_add
#'
#' add a dataset to a datastore
#'
#' @param ds path to datastore
#' @param obj the R-data object that should be put into the datastore
#' @param ds_name name of data-object
#' @param version (number) version of data-object
#'
#' @return \code{TRUE} if the data-object was successfully added to the datastore
#' @export
#'
#' @examples
#' ## not yet
ds_add <- function(ds, obj, ds_name, version) {
  ds_isvalid(ds)
  stopifnot(is_scalar_character(ds_name))
  stopifnot(is_scalar_integerish(version))

  # version already exists?
  if (ds_exists(ds, ds_name = ds_name, version = version, verbose = FALSE)) {
    err <- paste(substitute(ds_name), "in version", version, "already exists in datastore.")
    stop(err, call. = FALSE)
  }

  s <- ds_sep()
  p <- ds_filepath(ds)
  fout <- file.path(p,
    paste0(ds_name, s, version, s, ds_timestamp(), ".rds")
  )
  saveRDS(obj, file = fout, compress = TRUE)

  ds_update_index(ds, verbose = FALSE)
  msg <- paste(substitute(obj), "in version", version, "added to the datastore.")
  message(msg)
  return(invisible(TRUE))
}