All files pushId.js

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/* eslint-disable */
// Modeled after base64 web-safe chars, but ordered by ASCII.
var PUSH_CHARS = '-0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz';
 
// Timestamp of last push, used to prevent local collisions if you push twice in one ms.
var lastPushTime = 0;
 
// We generate 72-bits of randomness which get turned into 12 characters and appended to the
// timestamp to prevent collisions with other clients.  We store the last characters we
// generated because in the event of a collision, we'll use those same characters except
// "incremented" by one.
var lastRandChars = [];
 
export default () => {
  var now = new Date().getTime();
  var duplicateTime = (now === lastPushTime);
  lastPushTime = now;
 
  var timeStampChars = new Array(8);
  for (var i = 7; i >= 0; i--) {
    timeStampChars[i] = PUSH_CHARS.charAt(now % 64);
    // NOTE: Can't use << here because javascript will convert to int and lose the upper bits.
    now = Math.floor(now / 64);
  }
  Iif (now !== 0) {
    throw new Error('We should have converted the entire timestamp.');
  }
 
  var id = timeStampChars.join('');
 
  Eif (!duplicateTime) {
    for (i = 0; i < 12; i++) {
      lastRandChars[i] = Math.floor(Math.random() * 64);
    }
  } else {
    // If the timestamp hasn't changed since last push, use the same random number, except incremented by 1.
    for (i = 11; i >= 0 && lastRandChars[i] === 63; i--) {
      lastRandChars[i] = 0;
    }
    lastRandChars[i]++;
  }
  for (i = 0; i < 12; i++) {
    id += PUSH_CHARS.charAt(lastRandChars[i]);
  }
  Iif (id.length !== 20) {
    throw new Error('Length should be 20.');
  }
 
  return id;
};