Generating time slots using moment.js with start time & end time range

//Data
let x = {
slotInterval: 30,
openTime: '21:00',
closeTime: '05:00'
};

//Format the time
let startTime = moment(x.openTime, "HH:mm");

//Format the end time and the next day to it
let endTime = moment(x.closeTime, "HH:mm").add(1, 'days');

//Times
let allTimes = [];

//Loop over the times - only pushes time with 30 minutes interval
while (startTime < endTime) {
//Push times
allTimes.push(startTime.format("HH:mm"));
//Add interval of 30 minutes
startTime.add(x.slotInterval, 'minutes');
}

console.log(allTimes);