raiderx/synctime-demo

Library for time synchronization on the client

Sync Time Demo

Library for time synchronization on the client.

Requirements

SyncTime requires jQuery 1.5.

Initialization

Use init() method to initialize synchronisation:

SyncTime.init();

Also you can initialize synchronisation with different parameters:

SyncTime.init({ url: '/synctime', method: 'POST' });

Synchronisation can be initialized with the following parameters:

• now

  Custom function that returns current timestamp in milliseconds.

• ajax

  Custom function that makes AJAX request, by default it is jQuery $.ajax.

• url

  A string containing the URL to which the request is sent, by default it is synctime.

• method

  The HTTP method to use for request, by default it is GET.

• minRequestCount

  Minimum number of requests sufficient for time synchronisation, by default it is 5.

• resyncInterval

  Interval in seconds between requests to the server, by default it is 0 i.e. no requests.

• maxOffsetsCount

  Maximum number of offsets between client and server time, by default it is 20.

• storage

  Object that stores synchronisation data, by default such data is stored in cookie. You can use custom storage, for example:

  function FooStorage() {
  
      var _value = null;
  
      this.getItem = function () {
          return _value;
      };
  
      this.setItem = function (k, v) {
          _value = v;
      };
  }
  
  SyncTime.init({ storage: new FooStorage() });

  You can use localStorage:

  SyncTime.init({ storage: localStorage });

• dataKey

  Name of the key for synchronisation data, by default it is SyncTimeData.

Using

SyncTime.sync() makes a number of requests to the server. It passes the client timestamp in milliseconds in UTC time.

GET /synctime?t=1475568396666

The server sends response in JSON format with time offset and original timestamp.

{"offset":6,"origtime":1475568396666}

In order to get a JavaScript Date instance you can use:

var now = SyncTime.newDate();

It is similar to:

var now = new Date();

In order to get the number of milliseconds elapsed since 1 January 1970 00:00:00 UTC you can use:

var now = SyncTime.getTime();

It is similar to:

var now = new Date().getTime();