R/cbs4_get_datasets.R

In statistiekcbs/cbsccb: Statistics Netherlands (CBS) Open Data API Client v4

#' Get available datasets
#'
#' Get the available datasets from open data portal statline.
#'
#' Setting the catalog to `NULL` will return all
#' @note the datasets are downloaded only once per R session and cached. Subsequent calls to
#' `cbs4_get_datasets` will use the results of the first call.
#' @example ./example/cbs4_get_datasets.R
#' @param catalog only show the datasets from that catalog. If `NULL`
#' all datasets of all catalogs will be returned.
#' @param convert_dates Converts date columns in Date-Time type (in stead of `character`)
#' @param base_url base url of the CBS OData 4 API
#' @param verbose Should the url request be printed?
#' @return [data.frame()] with publication metadata of tables.
#' @family datasets
#' @export
cbs4_get_datasets <- function( catalog = "CBS"
                             , convert_dates = TRUE
                             , verbose = getOption("cbsodata4.verbose", FALSE)
                             , base_url = getOption("cbsodata4.base_url", BASEURL4)
                             ){
  path_cache <- file.path(tempdir(), "datasets.rds")

  if (file.exists(path_cache)){
    if (verbose) {
      message("Reading datasets from cache: ", path_cache)
    }
    ds <- readRDS(path_cache)
  } else {
    ds <- get_value( file.path(base_url, "Datasets")
                   , verbose = verbose
                   )

    saveRDS(ds, path_cache)
  }

  if (!is.null(catalog)){
    ds <- ds[ds$Catalog %in% catalog,]
  }

  if (isTRUE(convert_dates)){
    dates <- c("Modified","ObservationsModified")
    ds[, dates] <- lapply(ds[, dates], as.POSIXct)
  }

  ds
}

#' cbs4_get_toc is an alias for cbs4_get_datasets.
#' @export
#' @rdname cbs4_get_datasets
cbs4_get_toc <- cbs4_get_datasets