Retry logic for promises

retry-promise.js

/**
 * Retry a promise until success, up to a certain number of times.
 * Returns the last error if it reaches maximum attempts.
 *
 * @param maxTries {Number} positive integer
 * @param p {Promise}
 * @return {Promise}
 */
function retry (maxTries, p) {
  var tries = 0;
  var iter = function() {
    tries++;
    return p().catch(function(error) {
      console.log(">>> Errored on try " + tries + "/" + maxTries)
      if (tries >= maxTries) {
        return Promise.reject(error);
      } else {
        return iter();
      }
    });
  };
  return iter();
}