R/sanitize-token.R

In REDCapR: Interaction Between R and REDCap

#' @title Validate and sanitize the user's REDCap token
#'
#' @description Verifies the token is nonmissing and conforms to the legal
#' pattern of a 32-character hexadecimal value.
#' Each character must be an (a) digit 0-9, (b) uppercase letter A-F, or
#' (c) lowercase letter a-f.
#' #' Trailing line endings are removed.
#'
#' @param token The REDCap token. Required.
#'
#' @return The token, without a terminal newline character.
#'
#' @note Contact your institution's REDCap administrator for more information
#' about your project-specific token.
#'
#' @author Hao Zhu, Benjamin Nutter, Will Beasley, Jordan Mark Barbone
#'
#' @examples
#' secret_token_1 <- "12345678901234567890123456ABCDEF"
#' secret_token_2 <- "12345678901234567890123456ABCDEF\n"
#' secret_token_3 <- "12345678901234567890123456abcdef"
#' REDCapR::sanitize_token(secret_token_1)
#' REDCapR::sanitize_token(secret_token_2)
#' REDCapR::sanitize_token(secret_token_3)

#' @export
sanitize_token <- function(token) {
  pattern <- "^([0-9A-Fa-f]{32})(?:\\n)?$"

  if (is.na(token)) {
    stop(
      "The token is `NA`, not a valid 32-character hexademical value."
    )
  } else if (nchar(token) == 0L) {
    stop(
      "The token is an empty string, ",
      "not a valid 32-character hexademical value."
    )
  } else if (!grepl(pattern, token, perl = TRUE)) {
    stop(
      "The token is not a valid 32-character hexademical value."
    )
  }

  sub(pattern, "\\1", token, perl = TRUE)
}