Swift Get URLSessionDataTask start time / current operation time

Question

I have a URLSessionDataTask instance and I would like to know when the operation started (a Date object) so I can calculate how much time has elapsed.

I've found URLSessionTaskTransactionMetrics in Apple's documentation (https://developer.apple.com/documentation/foundation/urlsessiontasktransactionmetrics#declarations) but this does not show how to get the transactionMetrics property, unless I'm missing something obvious.

Answer 1

Assuming you have already set your view controller as the URLSessionTaskDelegate, you just need to override url session didFinishCollecting metrics method, iterate over the metrics transactionMetrics and get its fetchStartDate:

func urlSession(_ session: URLSession, task: URLSessionTask, didFinishCollecting metrics: URLSessionTaskMetrics) {
    for metric in metrics.transactionMetrics {    
        print(task.response?.url ?? "", metric.fetchStartDate?.description(with: .current) ?? "")
    }
}