Convert ISO 8601 duration to human-readable text in Kotlin

Question

I have an ISO duration of ‘PT11M1S’ (from the YouTube API). I know it means 11 minutes and 1 second, but is there any way I can convert it automatically in Kotlin into text that makes sense to the user (instead of the ‘PT11M1S’ string)?

Thanks!

Answer 1

Target: Java 8+

Use java.time to get a Duration object. There doesn't seem to be a great formatting solution, and the replaceAll one does not work on Kotlin Strings, so here is a Kotlin equivalent:

fun humanReadableDuration(s: String): String = java.time.Duration.parse(s).toString()
        .substring(2).toLowerCase().replace(Regex("[hms](?!\$)")) { "${it.value} " }

fun main() = println(humanReadableDuration("PT11M1S"))  // prints "11m 1s"

The Regex adds spaces after h/m/s but NOT if it's the end of the string to avoid a trailing space.

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Target: Any

Since you start with a String already you could avoid the Duration object entirely:

fun humanReadableDuration(s: String): String = s.substring(2)
        .toLowerCase().replace(Regex("[hms](?!\$)")) { "${it.value} " }