Here is the code excerpt:
func mapping(map: Map) {
time <- (map[\"time\"], TransformOf(fromJSON: {
let dateFormatter
From Technical Q&A QA1480 – NSDateFormatter and Internet Dates (emphasis added):
On the other hand, if you're working with fixed-format dates, you should first set the locale of the date formatter to something appropriate for your fixed format. In most cases the best locale to choose is "en_US_POSIX", a locale that's specifically designed to yield US English results regardless of both user and system preferences.
This will prevent the date from being interpreted according to the user's regional settings:
let dateFormatter = DateFormatter()
// Set the locale first ...
dateFormatter.locale = Locale(identifier: "en_US_POSIX")
// ... and then the date format:
dateFormatter.dateFormat = "HH:mm:ss"
// ...
See also What is the best way to deal with the NSDateFormatter locale "feechur"?.