onServiceLost producing NullPointerException

[paddykily]

I have the below code in a background service.

I also tried JmDNSDriver but thats results in the following error
W/art: Failed to open zip archive '/system/framework/qcom.fmradio.jar': I/O Error

val rxBonjour = RxBonjour.Builder()
                .platform(AndroidPlatform.create(this))
                .driver(NsdManagerDriver.create(this))
                .create()

val nsdDisposable = rxBonjour.newDiscovery("_octoprint._tcp")
    .subscribeOn(Schedulers.io())
    .observeOn(AndroidSchedulers.mainThread())
    .subscribe(
        { event ->
            when(event) {
                is BonjourEvent.Added -> println("Resolved Service: ${event.service}")
                is BonjourEvent.Removed -> println("Lost Service: ${event.service}")
            }
        },
        { error -> println("Error during Discovery: ${error.message}") }
    )

com.robo3d E/AndroidRuntime: FATAL EXCEPTION: NsdManager
                                                            Process: com.robo3d, PID: 10842
                                                            kotlin.KotlinNullPointerException
                                                                at de.mannodermaus.rxbonjour.BonjourService.<init>(Models.kt:27)
                                                                at de.mannodermaus.rxbonjour.drivers.nsdmanager.ExtensionsKt.toLibraryModel(Extensions.kt:36)
                                                                at de.mannodermaus.rxbonjour.drivers.nsdmanager.NsdManagerDiscoveryEngine$NsdDiscoveryListener.onServiceLost(NsdManagerDiscoveryEngine.kt:61)
                                                                at android.net.nsd.NsdManager$ServiceHandler.handleMessage(NsdManager.java:336)
                                                                at android.os.Handler.dispatchMessage(Handler.java:102)
                                                                at android.os.Looper.loop(Looper.java:148)
                                                                at android.os.HandlerThread.run(HandlerThread.java:61)

[mannodermaus]

Thanks for reporting! The only fields expected to be non-null by BonjourService are the service name, type & port. I suspected that this information has to always be there even when a service is lost, but I guess it doesn't. Is this issue reproducible to you? If so, could you place a breakpoint in NsdManagerDiscoveryEngine#L61, just before the call to toLibraryModel() is made? If I can have a look at the properties of that service object, we might be able to figure out which info may not be available to NsdManager at that time.

[Kutashov]

Good day! I have the same issue.
Here is stacktrace for NsdManagerDiscoveryEngine#L61:
name: SampleName, type: _http._tcp., host: null, port: 0

[mannodermaus]

Thanks for the insight! It probably comes down to the host address of a "lost" Service object not being available. I will examine and push a fix to the next RC shortly.

[Kutashov]

Thank you for this solution!
We can just use JmDNS driver for now. However, this driver returns two addresses for me:
BonjourService(type=_workstation._tcp.local., name=GoZeroconf, v4Host=/192.168.56.1
BonjourService(type=_workstation._tcp.local., name=GoZeroconf, v4Host=/192.168.1.68
First one is virtualbox adapter. And I have no idea how to make it go without deleting VB or moving to another machine.
BTW, it takes some time for the server to be visible in BonjourService. Possibly, because there are no dns entries in a router dns table. And I suppose, we are not capable to affect it.

[SergeyBurlaka]

Have the same isssue with NsdManagerDriver. When use NsdManagerDriver my app just always crashes. There is solution?