mixpanel/lib/utils.js

A simple server-side API for mixpanel

/**
 * helper to wait for all callbacks to complete; similar to `Promise.all`
 * exposed to metrics object for unit tests
 * @param {Array} requests
 * @param {Function} handler
 * @param {Function} callback
 */
exports.async_all = function (requests, handler, callback) {
  let total = requests.length,
    errors = null,
    results = [],
    done = function (err, result) {
      if (err) {
        // errors are `null` unless there is an error, which allows for promisification
        errors = errors || [];
        errors.push(err);
      }
      results.push(result);
      if (--total === 0) {
        callback(errors, results);
      }
    };

  if (total === 0) {
    callback(errors, results);
  } else {
    for (let i = 0, l = requests.length; i < l; i++) {
      handler(requests[i], done);
    }
  }
};

/**
 * Validate type of time property, and convert to Unix timestamp if necessary
 * @param {Date|number} time - value to check
 * @returns {number} Unix timestamp
 */
exports.ensure_timestamp = function (time) {
  if (!(time instanceof Date || typeof time === "number")) {
    throw new Error(
      "`time` property must be a Date or Unix timestamp and is only required for `import` endpoint",
    );
  }
  return time instanceof Date ? time.getTime() : time;
};

/**
 * Asserts that the provided logger object is valid
 * @param {CustomLogger} logger - The logger object to be validated
 * @throws {TypeError} If the logger object is not a valid Logger object or
 *   if it is missing any of the required methods
 */
exports.assert_logger = function (logger) {
  if (typeof logger !== "object") {
    throw new TypeError(`"logger" must be a valid Logger object`);
  }

  ["trace", "debug", "info", "warn", "error"].forEach((method) => {
    if (typeof logger[method] !== "function") {
      throw new TypeError(`Logger object missing "${method}" method`);
    }
  });
};