in aws-ecs-server/src/main/resources/buildServerResources/ecsSettings.js [450:455]
generateNewImageId: function () {
if($j.isEmptyObject(this.imagesData)) return 1;
else return Math.max.apply(Math, $j.map(this.imagesData, function callback(currentValue) {
return currentValue['source-id'];
})) + 1;
},