get unix timestamp from date, date format is YYYY-MM-DD

gistfile1.js

function getUnixTimeFromDate (date) {
	if ( typeof(date) === 'undefined' ) {
		throw 'Date is required';
	}

	// using lodash _.isEmpty if available
	if ( typeof window._.isEmpty === 'function' && _.isEmpty(date) ) {
		throw 'Date cannot be empty.';
	} else if( date === '' || date == '' ) {
		throw 'Date cannot be empty.';
	}

  	var dob = new Date(date).getTime() / 1000;
  	dob = parseInt(dob);

  	return dob;
}

// example
// console.log( getUnixTimeFromDate('2012-08-21') );