shields/lib/log.js

// Zero-pad a number in a string.
// eg. 4 becomes 04 but 17 stays 17.
function pad(string) {
  string = String(string);
  return (string.length < 2) ? ('0' + string) : string;
}

// Compact date representation.
// eg. 0611093840 for June 11, 9:38:40 UTC.
function date() {
  const date = new Date();
  return pad(date.getUTCMonth() + 1) +
    pad(date.getUTCDate()) +
    pad(date.getUTCHours()) +
    pad(date.getUTCMinutes()) +
    pad(date.getUTCSeconds());
}

module.exports = function log(...msg) {
  console.log(date(), ...msg);
};

module.exports.error = function error(...msg) {
  console.error(date(), ...msg);
};