How to post data to Firestore as Timestamp data type - swift - swift

Question

I wonder how can I post data as String to Firestore as Timestamp. I am creating a sample app which store data on tableView and data are going to sort base on Timestamp.
So, in programming I have tried to get current time and date as String but I don't know how to set data to Firestore as field is Timestamp. When i query data from Firestore i want to sort data base on Timestamp.
let currentDateTime = Date()
// initialize the date formatter and set the style
let formatter = DateFormatter()
formatter.timeStyle = .long
formatter.dateStyle = .long
// get the date time String from the date object
formatter.string(from: currentDateTime)
Timestamp in Firestore contain date and time.
How can I post data as String to Firestore as Timestamp?

Answer 1

If I understand correctly, you want to store a file under a time stamp or date in Firestore?
You seem to be doing a Time stamp literally as a date, a much simpler way would be storing it as a Time stamp this way as it will just be a number that will be ordered in Firestore.
let timestamp = Int(NSDate.timeIntervalSinceReferenceDate*1000).description
Image Link : This will be the end result

Answer 2

Why do you want to post it as String? Here's my approach with an Int instead
let timestamp = Int(Date().timeIntervalSince1970) // gives you an Int like 1534840591
Then when you parse it from Firebase, pass it to a func like something like this to convert that Int timestamp into a date:
func timestampIntToString(integerTime: Int, timestampLabel: UILabel) {
let timestampDate = Date(timeIntervalSince1970: Double(integerTime))
let now = Date()
let components = Set<Calendar.Component>([.second, .minute, .hour, .day, .weekOfMonth])
let difference = Calendar.current.dateComponents(components, from: timestampDate, to: now)
var timeText = ""
if difference.second! <= 0 {
timeText = "now"
}
if difference.second! > 0 && difference.minute! == 0 {
timeText = "\(difference.second!) sec ago"
}
if difference.minute! > 0 && difference.hour! == 0 {
timeText = "\(difference.minute!) min"
}
if difference.hour! > 0 && difference.day! == 0 {
timeText = "\(difference.hour!)h"
}
if difference.day! > 0 && difference.weekOfMonth! == 0 {
timeText = (difference.day == 1) ? "\(difference.day!)day" : "\(difference.day!) days ago"
}
if difference.weekOfMonth! > 0 {
timeText = (difference.weekOfMonth == 1) ? "\(difference.weekOfMonth!) w" : "\(difference.weekOfMonth!)w"
}
timestampLabel.text = timeText
}