R/read_disaster_risk_area.R

In geobr: Download Official Spatial Data Sets of Brazil

#' Download spatial data of disaster risk areas
#'
#' @description
#' This function reads the the official data of disaster risk areas in Brazil
#' (currently only available for 2010). It specifically focuses on geodynamic
#' and hydro-meteorological disasters capable of triggering landslides and floods.
#' The data set covers the whole country. Each risk area polygon (known as 'BATER')
#' has unique code id (column 'geo_bater'). The data set brings information on
#' the extent to which the risk area polygons overlap with census tracts and block
#' faces (column "acuracia") and number of ris areas within each risk area (column
#' 'num'). Original data were generated by IBGE and CEMADEN. For more information
#' about the methodology, see deails at \url{https://www.ibge.gov.br/geociencias/organizacao-do-territorio/tipologias-do-territorio/21538-populacao-em-areas-de-risco-no-brasil.html}
#'
#' @template year
#' @template code_muni
#' @template simplified
#' @template output
#' @template showProgress
#' @template cache
#' @template verbose
#'
#' @return An `"sf" "data.frame"` OR an `ArrowObject`
#'
#' @export
#'
#' @examplesIf identical(tolower(Sys.getenv("NOT_CRAN")), "true")
#' # Read all disaster risk areas in an specific year
#' d <- read_disaster_risk_area(year = 2010)
#'
#' # Read disaster risk areas in a given municipality
#' d <- read_disaster_risk_area(year = 2010, code_muni = 2927408)
#'
#' # Read disaster risk areas in a given state
#' d <- read_disaster_risk_area(year = 2010, code_muni = "AC")

read_disaster_risk_area <- function(year,
                                    code_muni = "all",
                                    simplified = TRUE,
                                    output = "sf",
                                    showProgress = TRUE,
                                    cache = TRUE,
                                    verbose = TRUE){

  # Get metadata
  temp_meta <- select_metadata(
    geography="disasterriskareas",
    year = year,
    simplified = simplified,
    verbose = verbose
  )

  # check if download failed
  if (is.null(temp_meta)) { return(invisible(NULL)) }

  # download file and open arrow dataset
  temp_arrw <- download_parquet(
    filename_to_download = temp_meta$file_name,
    showProgress = showProgress,
    cache = cache
  )

  # check if download failed
  if (is.null(temp_arrw)) { return(invisible(NULL)) }

  # FILTER
  temp_arrw <- filter_arrw(temp_arrw, code = code_muni)

  # convert to sf
  temp <- convert_output(temp_arrw, output)

  return(temp)

}