R/file_stable.R

In raubreywhite/fhi: FHI Convenience Functions

file_open <- function(file = tempfile()) {
  retval <- FALSE
  if (fs::path_ext(file) %in% c("csv")) {
    retval <- tryCatch(
      {
        a <- data.table::fread(file, nrows = 1)
        return(FALSE)
      },
      error = function(cond) {
        return(TRUE)
      }
    )
  }
  return(retval)
}

#' Is the file stable (size not increasing/decreasing)?
#'
#' @param file The file of interest
#' @param delay Number of seconds between checking file size a second time
#' @export
file_stable <- function(file = tempfile(), delay = 10) {
  if (file.exists(file)) {
    size1 <- file.info(file)$size[1]
    Sys.sleep(delay)
    size2 <- file.info(file)$size[1]
    if (size1 == size2) {
      if (!file_open(file)) {
        return(TRUE)
      }
    }
  }
  return(FALSE)
}