Swift

Cancel HTTP Get Async Task if not Completed after a Max Time

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Demonstrates how to wait a maximum amount of time for an asynchronous task to completed. If not completed in the allotted amount of time, the task is cancelled. Swift

func chilkatTest() {
    var success: Bool = false

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    let http = CkoHttp()!

    // Set some timeouts, in seconds:
    http.connectTimeout = 15
    // ReadTimeout specifies the max number of seconds that must elapse when no additional data is received before
    // timing out.  For example, if a server sends a 300 byte response at the rate of 1 byte per second, then
    // ReadTimeout would never cause a timeout because there is never a 15 second interval when nothing arrives.
    http.readTimeout = 15

    var url: String? = "https://your-url.com/something"
    var task: CkoTask? = http.quickGetStrAsync(url: url)
    task!.run()

    // Wait a maximum of waitMaxMs for the task (i.e. the HTTP GET) to complete.
    // The Wait method returns when the task has been canceled, aborted, or completed, or when the max allotted time has passed.
    var waitMaxMs: Int = 20000
    task!.wait(maxWaitMs: waitMaxMs)

    // At this point, the GET may or may not have completed.  
    // Rather than checking the Task status, we can call task.Cancel because
    // if the Task is no longer running (because it already completed, was canceled or aborted), then the 
    // call to Cancel is a NO-OP (meaning it does nothing and the Task's status is unaffected).
    // Also, task.Cancel returns true if the task was in the "queued" or "running" state and was canceled or aborted. 
    // The method returns false if the task has any other status.
    var wasCanceled: Bool = task!.cancel()
    if wasCanceled == true {
        print("The HTTP GET took too long and was canceled.")
    }
    else {
        // Find out what happened.
        if task!.statusInt.intValue == 7 {
            // The task completed, which means the background thread's call to QuickGetStr completed
            // with success or failure.  Find out which...
            if task!.taskSuccess == true {
                // Get the string response for the call to QuickGetStr (which happened in Chilkat's background thread).
                var responseStr: String? = task!.getResultString()
                print("\(responseStr!)")
                print("HTTP GET successful!")
            }
            else {
                print("HTTP GET failed prior to waitMaxMs...")
                print("\(task!.resultErrorText!)")
            }

        }
        else {
            // The task must've been canceled or aborted by some other means..
            print("Task did not complete.  Final status: \(task!.status!)")
        }

    }

    task = nil

}