Add retry logic for Wi-Fi LAN advertising to avoid issues on iOS 14.8.1 about nearby HOT 7 OPEN

@bourdakos1 forgot to tell that the startDiscovery is working as expected

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Thanks for verifying! I need to look into how to properly handle this case

from nearby.

Awesome! So it is just a matter of retrying. I'll update this issue to reflect the need for adding internal retry logic for Wi-Fi LAN

from nearby.

Thanks for answering so fast! I will keep subscribed on this issue so we can update the lib on our end :)

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It looks like it failed to start listening for incoming connections, but the system didn't return any an explicit errors. My best guess is that the listener transitioned to the nw_listener_state_waiting which isn't a fatal error, but will end in a fatal nearby error, since we don't attempt retries: https://developer.apple.com/documentation/network/nw_listener_state_t/nw_listener_state_waiting?language=objc

However, I don't have an iOS 14.8.1 device to verify. Do you mind trying to add some logs here:

I can also push an update with more logs if thats easier, but that might take some time to get reviewed/submitted

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It looks like your guessing is correct,

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I made this workaround

private func startAdvertise(nearbyMessage: NearbyMessage, retryCount: Int) {
        print("[NearbyManager] Retrying startAdvertise: \(retryCount)")

        guard
            let nearbyMessageData = nearbyMessage.dataValue,
            retryCount > 0
        else {
            return
        }

        advertiser.startAdvertising(
            using: nearbyMessageData,
            completionHandler: { error in
                guard let error = error else {
                    print("[NearbyManager] Success on startAdvertising")
                    return
                }

                print("[NearbyManager] Failed to advertise: \(error.localizedDescription)")

                let timer = Timer.scheduledTimer(withTimeInterval: 1.0, repeats: false) { [weak self] timer in
                    self?.startAdvertise(nearbyMessage: nearbyMessage, retryCount: retryCount-1)
                }
                timer.fire()
            }
        )
    }

Eventually it will work:

[NearbyManager] Retrying startAdvertise: 10
[NearbyManager] Failed to advertise: The operation couldn’t be completed. (com.google.nearby.connections.error error 11.)
[NearbyManager] Retrying startAdvertise: 9
[NearbyManager] Failed to advertise: The operation couldn’t be completed. (com.google.nearby.connections.error error 11.)
[NearbyManager] Retrying startAdvertise: 8
[NearbyManager] Success on startAdvertising

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