data-raw/get_buoy_location.R

In andybeet/ndbcbuoy: Pulls and sorts buoy data from ndbc

#' Grabs station info for all stations
#'
#' Uses output fron \code{get_buoy_names} and then parse each of the buoys webpages to extract common name, location, etc
#'
#'@param buoyData Data frame. Output from get_buoy_names
#'
#'


get_buoy_location <- function(buoyData){

  webPageLink <- "https://www.ndbc.noaa.gov/station_history.php?station="

  buoyTable <- data.frame()

  for (ibuoy in 1:dim(buoyData)[1]) {
    abuoy <- buoyData$ID[ibuoy]
    message(paste0("buoy ",ibuoy, " of ",dim(buoyData)[1]))

    # form webpage link, get page and then line with info we need
    buoyPage <- paste0(webPageLink,abuoy)
    res <- tryCatch({
      htmlPage <- readLines(buoyPage)
      res <- TRUE
    }, error = function(e) {
      message(paste0("Warning: No webpage for buoy ",abuoy))
      res <- FALSE
    }, warning = function(w) {
      message(paste0("Warning: No webpage for buoy ",abuoy))
      res <- FALSE
    })

    if (!res) {
      buoy <- data.frame(buoyData[ibuoy,],LAT=NA,LON=NA,STATION_LOC=NA,STATION_NAME=NA)

    } else {

      line <- htmlPage[grepl("DC\\.description",htmlPage)]
      # now split line and grab pieces
      locString <- strsplit(line,toupper(abuoy))[[1]][2]
      locString <- strsplit(locString,"\\s-\\s")

      # scrape lat and long
      latLong <- sub("^\\s","",locString[[1]][1])
      latLong <- sub("\\(","",latLong)
      latLong <- sub("\\)","",latLong)
      latLongDir <- strsplit(latLong,"\\s")
      latLongDir[[1]][2] <- sub("\\.\"$","",latLongDir[[1]][2])

      islat <- (grepl("[nN]",latLongDir[[1]][1]) * 2) -1 # convert EW to +1, -1
      lat <- as.numeric(sub("[A-z]","",latLongDir[[1]][[1]])) * islat
      islon <- (grepl("[eE]",latLongDir[[1]][2]) * 2) -1
      lon <- as.numeric(sub("[A-z]","",latLongDir[[1]][[2]])) * islon

      print(length(locString[[1]]))
      print(line)
      print("###########################################################")
      if (length(locString[[1]]) == 3) { # latlon, station num, station name
        name <- locString[[1]][2]
        loc <- strsplit(locString[[1]][3],"\"")[[1]][1]

      } else if (length(locString[[1]]) == 2) { #latlon, station name
        name <- NA
        loc <- strsplit(locString[[1]][2],"\"")[[1]][1]

      } else if (length(locString[[1]]) == 4){
        name <- paste(locString[[1]][2:3],collapse = "-")
        loc <- strsplit(locString[[1]][4],"\"")[[1]][1]
        print(name)
        print(loc)
      } else if (length(locString[[1]]) > 4) {
        print(locString)
        stop("FORMAT")
      }

      buoy <- data.frame(buoyData[ibuoy,],LAT=lat,LON=lon,STATION_LOC=loc,STATION_NAME=name)
    }

    buoyTable <- rbind(buoyTable,buoy)

  }
  buoyData <- buoyTable

  return(buoyData)
}