How to differentiate sources with HealthKit sleep query - ios

Question

I'm currently using the following code to query for the number of hours the user was asleep in the last 24 hours:
func getHealthKitSleep() {
let healthStore = HKHealthStore()
let sortDescriptor = NSSortDescriptor(key: HKSampleSortIdentifierEndDate, ascending: false)
// Get all samples from the last 24 hours
let endDate = Date()
let startDate = endDate.addingTimeInterval(-1.0 * 60.0 * 60.0 * 24.0)
let predicate = HKQuery.predicateForSamples(withStart: startDate, end: endDate, options: [])
// Sleep query
let sleepQuery = HKSampleQuery(
sampleType: HKObjectType.categoryType(forIdentifier: HKCategoryTypeIdentifier.sleepAnalysis)!,
predicate: predicate,
limit: 0,
sortDescriptors: [sortDescriptor]){ (query, results, error) -> Void in
if error != nil {return}
// Sum the sleep time
var minutesSleepAggr = 0.0
if let result = results {
for item in result {
if let sample = item as? HKCategorySample {
if sample.value == HKCategoryValueSleepAnalysis.asleep.rawValue && sample.startDate >= startDate {
let sleepTime = sample.endDate.timeIntervalSince(sample.startDate)
let minutesInAnHour = 60.0
let minutesBetweenDates = sleepTime / minutesInAnHour
minutesSleepAggr += minutesBetweenDates
}
}
}
self.sleep = Double(String(format: "%.1f", minutesSleepAggr / 60))!
print("HOURS: \(String(describing: self.sleep))")
}
}
// Execute our query
healthStore.execute(sleepQuery)
}
This works great if the user has only one sleep app as the source for the data. The problem is if the user is using 2 sleep apps, for example, as sources, the data will be doubled. How can I differentiate the sources? If able to differentiate the sources, I would like to either only grab data from one source, or maybe take the average of the sources.

Answer 1

When you're looping over the samples, you can access information about the source for each. I only accept a single source, so I just keep a variable of the source name and if the current sample has a different source name I continue looping without processing the data from that sample, but you could combine the data in other ways if you wanted to.
Here's how to access the source info:
if let sample = item as? HKCategorySample {
let name = sample.sourceRevision.source.name
let id = sample.sourceRevision.source.bundleIdentifier
}
There's some more info on the HKSourceRevision object in the docs here.