Parsing ISO 8601 like duration in Luxon

Question

I have duration string that looks like:

1:16.352

where 1 is minutes part, 16 is seconds part and 352 is millisecond part.

I wanted to use Duration.fromISOTime but I get:

{
  "reason": "unparsable",
  "explanation": "the input \"1:16.352\" can't be parsed as ISO 8601"
}

Is there a clean way of parsing such duration in Luxon?

user_4131048 · Answer

Duration.fromISOTime does not work since 1:16.352 is not an ISO 8601 time string, the hour part is missing (see ISO 8601 Times).

A workaround to build a Luxon Duration object could be the following:

const DateTime = luxon.DateTime;
const Duration = luxon.Duration;

const startOfHour = DateTime.local().startOf('hour').toMillis();
const dt = DateTime.fromFormat("1:16.352", "m:ss.SSS"). toMillis();
const dur = Duration.fromMillis(dt - startOfHour);
console.log(dur.toFormat("m 'minute' s 'second' S 'millis'"));

user_296427 · Answer

Similarly to @VincenzoC I adjusted my input string:

const Duration = luxon.Duration;

var output;
const durationInput = "1:16.352"

if (durationInput.match(/:/g) || [].length === 1) {
  const semicolonLocation = durationInput.indexOf(":");

  if (semicolonLocation === 1) {
    output = "00:0" + durationInput;
  }

  if (semicolonLocation === 2) {
    output = "00:" + durationInput;
  }
}

console.log(Duration.fromISOTime(output));

user_11407695 · Answer

As I mentioned in the comments, you can use the fromObject static method combined with simply splitting the input into minutes, seconds, and milliseconds configuration options. In your case a trivial regular expression (\d+):(\d+)\.(\d+) should do the trick, no temporary dates or normalization required.

const { Duration } = luxon;
const durationInput = "1:16.352";

const fromCustom = (input) => {
  const [, minutes, seconds, milliseconds ] = input.match(/(\d+):(\d+)\.(\d+)/);
    
  return Duration.fromObject({
    minutes, seconds, milliseconds
  });
};

console.log(fromCustom(durationInput));

Parsing ISO 8601 like duration in Luxon

3 Answers