to_geo_json.R

to_geo_json <- function(x, ...){
  UseMethod('to_geo_json')
}

to_geo_json.data.frame <- function(x, lat = "latitude", lon = "longitude"){
  geo_json = vector('list', NROW(x))
  y = lapply(1:NROW(x), function(i){
    if (is.null(x[i,lat]) || is.null(x[i,lon])){
      return(NULL)
    } else {
      list(
        type = "Feature",
        geometry = list(
          type = "Point",
          coordinates = as.numeric(c(x[i,lon], x[i,lat])),
          properties = x[i,!(names(x) %in% c(lat, lon))]
        )
      )
    }
    setNames(Filter(function(z) !is.null(z), y), NULL)
  })
}