Retrieve firebase server time without setting it first

Question

Is there a way to obtain the server time without having to first set it? For example, I can simply do:

curl -X PUT -d '{".sv": "timestamp"}' https://SampleChat.firebaseIO-demo.com/servertime.json

which will return the server time, but this sets the value servertime within my firebase instance. I should note that I'm using the REST API.

Answer 1

You can retrieve the server time without writing it by using .info/serverTimeOffset:

var fbRef = new Firebase(URL);

var getServerTime = (function(ref) {
    var offset = 0;
    ref.child('.info/serverTimeOffset').on('value', function(snap) {
       offset = snap.val();
    });

    return function() {
       return Date.now() + offset;
    }
})(fbRef);

var now = getServerTime();