R/cetesb_retrieve_pol.R

In ropensci/qualR: An R package to download São Paulo and Rio de Janeiro air pollution data

#' Download criteria pollutants from CETESB QUALAR
#'
#' This function download the criteria pollutants from one air quality station
#' (AQS) of CETESB AQS network.
#' It will pad out the date with missing data with NA.
#' This function required to have
#' \href{https://seguranca.cetesb.sp.gov.br/Home/CadastrarUsuario}{an account}
#' in \href{https://qualar.cetesb.sp.gov.br/qualar/home.do}{CETESB QUALAR}.
#'
#' @param username User name of CETESB QUALAR
#' @param password User name's password of CETESB QUALAR
#' @param aqs_code Code of AQS
#' @param start_date Date to start downloading in dd/mm/yyyy
#' @param end_date  Date to end downloading in dd/mm/yyyy
#' @param verbose Print query summary
#' @param to_csv  Creates a csv file. FALSE by default
#' @param csv_path Path to save the csv file
#'
#' @return data.frame with O3, NO, NO2, PM2.5, PM10 and CO information.
#' Units are ug/m3 except for CO which is in ppm, and NOx which is in ppb.
#' @export
#'
#' @examples
#' \dontrun{
#' # Downloading criteria pollutants from Pinheiros AQS
#' # from January first to 7th of 2020
#' my_user_name <- "John Doe"
#' my_pass_word <- "drowssap"
#' pin_code <- 99 # Check with cetesb_aqs
#' start_date <- "01/01/2020"
#' end_date <- "07/01/2020"
#'
#' pin_pol <- cetesb_retrieve_pol(my_user_name, my_pass_word, pin_code,
#'                                start_date, end_date)
#'
#' }
cetesb_retrieve_pol <- function(username, password,
                                aqs_code, start_date,
                                end_date, verbose = TRUE,
                                to_csv = FALSE, csv_path = ""){

  # Check if aqs_code is valid
  aqs <- cetesb
  check_code <- check_cetesb_code(aqs, aqs_code)
  aqs_name <- check_code[1]
  aqs_code <- as.numeric(check_code[2])

  # Adding query summary
  if (verbose){
    message("Your query is:")
    message("Parameter: O3, NO, NO2, NOX, MP2.5, MP10, CO")
    message("Air quality station: ", aqs_name)
    message("Period: From ", start_date, " to ", end_date)
  }

  o3 <- cetesb_retrieve(username, password, 63,
                        aqs_code, start_date,
                        end_date, verbose = FALSE)

  no <- cetesb_retrieve(username, password, 17,
                        aqs_code, start_date,
                        end_date, verbose = FALSE)

  no2 <- cetesb_retrieve(username, password, 15,
                         aqs_code, start_date,
                         end_date, verbose = FALSE)

  nox <- cetesb_retrieve(username, password, 18,
                         aqs_code, start_date,
                         end_date, verbose = FALSE)

  pm25 <- cetesb_retrieve(username, password, 57,
                          aqs_code, start_date,
                          end_date, verbose = FALSE)

  pm10 <- cetesb_retrieve(username, password, 12,
                          aqs_code, start_date,
                          end_date, verbose = FALSE)

  co <- cetesb_retrieve(username, password, 16,
                        aqs_code, start_date,
                        end_date, verbose = FALSE)


  all_pol <- data.frame(date = o3$date,
                        o3 = o3$pol,
                        no = no$pol,
                        no2 = no2$pol,
                        nox = nox$pol,
                        co = co$pol,
                        pm10 = pm10$pol,
                        pm25 = pm25$pol,
                        aqs = o3$aqs,
                        stringsAsFactors = FALSE)

  cols_unchange <- -c(1, ncol(all_pol))
  all_pol[, cols_unchange] <- sapply(all_pol[, cols_unchange], as.numeric)

  message(paste(
    "Download complete for", unique(all_pol$aqs)
  ))

  if (to_csv){
    write_csv(all_pol, aqs_name, start_date, end_date, "POL", csv_path) # nocov
  }

  return(all_pol)
}