R/extras.R

In crypto2: Download Crypto Currency Data from 'CoinMarketCap' without 'API'

#' URL Creator
#'
#' @param path A path to append to the base URL
#'
#' @return A full URL string
#' @keywords internal
#'
#' @importFrom base64enc base64decode
#'
construct_url <- function(path,v=1) {
  if (v==1){
    base <- rawToChar(base64enc::base64decode("aHR0cHM6Ly9hcGkuY29pbm1hcmtldGNhcC5jb20vZGF0YS1hcGkvdjEv"))
  } else if (v==3) {
    base <- rawToChar(base64enc::base64decode("aHR0cHM6Ly9hcGkuY29pbm1hcmtldGNhcC5jb20vZGF0YS1hcGkvdjMv"))
  } else if (v=="3.1") {
    base <- rawToChar(base64enc::base64decode("aHR0cHM6Ly9hcGkuY29pbm1hcmtldGNhcC5jb20vZGF0YS1hcGkvdjMuMS8="))
  } else if (v=="agg") {
    base <- rawToChar(base64enc::base64decode("aHR0cHM6Ly9hcGkuY29pbm1hcmtldGNhcC5jb20vYWdnci92My8="))
  }
  return(paste0(base, path))
}
#' Parses json data from a string without revealing information about the source in case of an error
#'
#' @param ...
#'
#' @return A parsed JSON object
#' @keywords internal
#'
#' @importFrom jsonlite fromJSON
#'
safeFromJSON <- function(...) {
  result <- withCallingHandlers(
    tryCatch({
      # Attempt to parse JSON with suppressed warnings and messages
      suppressWarnings(suppressMessages({
        jsonlite::fromJSON(...)
      }))
    }, error = function(e) {
      # Return a custom, simpler error object
      simpleError("Unfortunately, the scraper could not find data with the sent api-call. If you believe this is a bug please report at https://github.com/sstoeckl/crypto2/issues")
    }),
    warning = function(w) {
      # Intercept warnings and handle them silently
      invokeRestart("muffleWarning")
    }
  )
  # Check if result is an error and stop if it is
  if (inherits(result, "error")) {
    stop(result$message, call. = FALSE)
  }
  result
}
#' checks the dater format (old/new) and converts to date
#'
#' @param date_str a date string
#'
#' @return a correct date
#' @keywords internal
#'
convert_date <- function(date_str) {
  # Remove all non-digit characters to check the format
  clean_date_str <- gsub("[^0-9]", "", date_str)

  # Determine the length of the string to guess the format
  if (nchar(clean_date_str) == 8) {
    # Assume the format is YYYYMMDD
    date_obj <- as.Date(clean_date_str, format = "%Y%m%d")
  } else if (nchar(date_str) == 10 && grepl("-", date_str)) {
    # Assume the format is YYYY-MM-DD
    date_obj <- as.Date(date_str, format = "%Y-%m-%d")
  } else {
    # Return NA if the format is not recognized
    warning("Date format not recognized. Expected 'YYYYMMDD' or 'YYYY-MM-DD'.")
    date_obj <- NA
  }

  return(date_obj)
}