Ruby Dates to Javascript the Easy Way

Whilst writing the queue management for Cafebop in Javascript using the excellent JQTouch library I came across a problem that I thought would be trivial to solve. In the end it was trivial but maybe it's so trivial that nobody ever mentions it so I couldn't find any info on it.

Basically, I wanted to instantiate a Javascript Date object from a Ruby Date object via a JSON call. The problem is that Javascript's Date object constructor can't parse the default string output by Ruby's Date#to_s.

However, it can parse an integer which is milliseconds since the Unix epoch. Ruby's Date#to_i outputs the number of seconds since the unix epoch. So, using my mad arithmetic skillz, I figured I can create a Javascript Date with:

new Date(rubyGeneratedInteger * 1000);

So my usage of it went something like this. In my rails model, I generate an appropriate integer representation of the timestamp:

I make that available to a JSON client through the controller:

And consume it from the Javascript client thus: