R/errors.R

In sckott/httsnap: High Level 'HTTP' Client

#' Error handler
#'
#' @export
#' @family dsl
#' @param .data Result of a call to \code{api}
#' @param fun A function, either defined in the session, or a function available in loaded
#' or name-spaced packges
#' @examples \dontrun{
#' # Use functions from httr
#' api('http://httpbin.org/status/503') %>%
#'  api_error_handler(stop_for_status)
#'
#' api('http://httpbin.org/status/404') %>%
#'  api_error_handler(warn_for_status)
#'
#' # Custom error handling functions
#' my_stop <- function(x) {
#'   if (x$status > 200) {
#'      warning("nope, try again", call. = FALSE)
#'   }
#' }
#' api("http://httpbin.org/status/404") %>%
#'  api_error_handler(my_stop)
#' }
api_error_handler <- function(.data, fun) {
  pipe_autoexec(toggle = TRUE)
  .data <- as.req(.data)
  fn_name <- deparse(substitute(fun))
  tmp <- setNames(list(fun), fn_name)
  modifyList(.data, list(error = tmp))
}