Bug in latest versions for Android?

[rrajivram]

Using mavsdk-2.1.0 and mavsdk-server-2.1.5 and Ardupilot SITL as the backend on an IP port I cannot get telemetry data on Android. Keeps telling me its retrying when I subscribe for position data. The only code I'm using beside server.run() and new System() is this in my main activity.kt :
fun runServer() {
MavsdkEventQueue.executor().execute({
val address = "tcp://192.168.29.118:5763"
val port = server.run(address)
Log.d(TAG, "port is $port")
if(port == 0) {
Log.e(TAG,"Unable to start server")
return@execute
}
drone = System("127.0.0.1",port)
isRunning = true
buttonText= "Destroy"
Log.i(TAG,"Server started")
setupSubscriptions()
})
}

@SuppressLint("CheckResult")
fun setupSubscriptions() {

    
    val altitude = drone.telemetry.position.subscribeOn(Schedulers.io())
        .observeOn(Schedulers.single())
        .subscribe({
            Log.d(TAG,"info : $it")
            Log.d(TAG,"Lat = " + it.latitudeDeg + ", Lon= " + it.longitudeDeg)
            latText = "   " + it.latitudeDeg
            longText = "   " + it.longitudeDeg
        }, Throwable::printStackTrace)
}

I've validated that QGC and mavproxy are able to both communicate with the SITL. When I change the mavsdk and server versions to 2.0 , then this works perfectly.

[julianoes]

mavsdk-server-2.1.5 seems quite old? Any chance you can try latest?

Do you have an example for me to test this with?

[rrajivram]

2.1.5 is the latest version on Apache maven.. the entire source code is what I posted - just added a button to start the server that calls start server (posted). I’ll try to post the entire kt file but it doesn’t have any new info.

…

On Tue, 28 Jan 2025 at 3:20 AM, Julian Oes ***@***.***> wrote: mavsdk-server-2.1.5 seems quite old? Any chance you can try latest? Do you have an example for me to test this with? — Reply to this email directly, view it on GitHub <#2500 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BIN4CD3G3CUZZGXTH6H2BFD2M2S2PAVCNFSM6AAAAABV5ZWYS2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDMMJWHE3TANBVGA> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[JonasVautherin]

Does it detect a mavlink system? Does your drone report receiving messages from MAVSDK over TCP?

[rrajivram]

Yes. I tried both arm and disarm commands and they worked fine. I wasn’t able to get any debugging output on ACKs , but I was able to see the SITL received and acted on the commands. Funnily enough, the SITL also disarmed automatically and notified my client it did so, even if I didn’t send the disarm command . I haven’t tried the commands yet with the 1.x versions - can try that if it will help.

…

On Tue, 28 Jan 2025 at 9:40 AM, Jonas Vautherin ***@***.***> wrote: Does it detect a mavlink system? Does your drone report receiving messages from MAVSDK over TCP? — Reply to this email directly, view it on GitHub <#2500 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BIN4CD5WBCA526754X42H2D2M37M5AVCNFSM6AAAAABV5ZWYS2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDMMJXHAYDCMRTGI> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[rrajivram]

And now its stopped working ; tried both version 1.2 and version 2.0. The entire source code is below :
`package com.example.greeting

import android.annotation.SuppressLint
import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.activity.enableEdgeToEdge
import androidx.activity.viewModels
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.padding
import androidx.compose.material3.Surface
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.tooling.preview.Preview
import androidx.compose.ui.unit.dp
import com.example.greeting.ui.theme.GreetingTheme
import android.util.Log
import androidx.compose.foundation.layout.Row
import androidx.compose.material3.Button
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.setValue
import io.mavsdk.MavsdkEventQueue;
import io.mavsdk.System;
import io.mavsdk.mavsdkserver.MavsdkServer;
import io.mavsdk.telemetry.Telemetry
import io.mavsdk.telemetry.Telemetry.Position
import io.reactivex.disposables.Disposable
import io.reactivex.Flowable;
import io.reactivex.functions.Consumer
import io.reactivex.functions.Function;
import io.reactivex.schedulers.Schedulers;
import kotlinx.coroutines.flow.Flow

class MainActivity : ComponentActivity() {
private val TAG = "MainActivity"

private val viewModel by viewModels<DroneModel>()
private val server = MavsdkServer()
private lateinit var drone: System
private var isRunning = false
private var disposables = mutableListOf<Disposable>()

var buttonText by  mutableStateOf("Start")
var altitudeText by mutableStateOf("AL")
var latText by mutableStateOf("LA")
var longText by mutableStateOf("LO")

@SuppressLint("QueryPermissionsNeeded")
override fun onCreate(savedInstanceState: Bundle?) {
    java.lang.System.setProperty("org.slf4j.simpleLogger.defaultLogLevel","Trace")
    Log.d(TAG,"in on create")
    super.onCreate(savedInstanceState)
    enableEdgeToEdge()
    setContent {
        GreetingTheme {
            Column(
                modifier = Modifier.fillMaxSize(),
                horizontalAlignment = Alignment.CenterHorizontally,
                verticalArrangement = Arrangement.Center
            ) {
                Row() {
                    Button(onClick = {
                        runOrDestroyServer()
                    }) {
                        Text(buttonText)
                    }
                }
                Row() {
                    Column {
                        Text("Altitude")
                    }
                    Column {
                        Text(altitudeText)
                    }
                }
                Row() {
                    Column {
                        Text("Latitude")
                    }
                    Column {
                        Text(latText)
                    }
                }
                Row() {
                    Column {
                        Text("Longitude")
                    }
                    Column {
                        Text(longText)
                    }
                }

            }
        }

    }
}

fun runOrDestroyServer() {
    if(isRunning) {
        stopServer()
    } else {
        runServer()
    }
}

fun runServer() {
    MavsdkEventQueue.executor().execute({
        val address = "tcp://192.168.29.118:5763"
        val port = server.run(address)
        Log.d(TAG, "port is $port")
        if(port == 0) {
            Log.e(TAG,"Unable to start server")
            return@execute
        }
        drone = System("127.0.0.1",port)
        isRunning = true
        buttonText= "Destroy"
        Log.i(TAG,"Server started")
        setupSubscriptions()
    })
}

@SuppressLint("CheckResult")
fun setupSubscriptions() {


    val altitude = drone.telemetry.position.subscribeOn(Schedulers.io())
        .observeOn(Schedulers.single())
        .subscribe({
            Log.d(TAG,"info : $it")
            Log.d(TAG,"Lat = " + it.latitudeDeg + ", Lon= " + it.longitudeDeg)
            latText = "   " + it.latitudeDeg
            longText = "   " + it.longitudeDeg
        }, Throwable::printStackTrace)


}

@SuppressLint("CheckResult")
fun stopServer() {
    if(!isRunning) {
        return
    }
    MavsdkEventQueue.executor().execute( {
        for(d in disposables ){
            d.dispose()
        }
        disposables.clear()
        drone.action.disarm().subscribe({},Throwable::printStackTrace)
        Thread.sleep(2000)
        drone.dispose()
        server.stop()

        isRunning = false
        buttonText = "Start"
    })
}

override fun onStart() {
    super.onStart()
    println("On start")
}

override fun onPause() {
    super.onPause()
    println("On Pause")
}

override fun onStop() {
    super.onStop()
    println("On Stop")
}

override fun onRestart() {
    super.onRestart()
    println("On Restart")
}

override fun onDestroy() {
    super.onDestroy()
    println("On Destroy")
}

override fun onResume() {
    super.onResume()
    println("On Resume")
}

}

`

Here are the log messages I'm seeing:
2025-01-28 10:45:58.089 6832-6892 Mavsdk com.example.greeting I MAVSDK version: v2.12.2
2025-01-28 10:45:58.090 6832-6892 MAVSDK-Server com.example.greeting D Running mavsdk_server with connection url: tcp://192.168.29.118:5763
2025-01-28 10:45:58.090 6832-6892 Mavsdk com.example.greeting I Waiting to discover system on tcp://192.168.29.118:5763...
2025-01-28 10:45:58.107 6832-6896 Mavsdk com.example.greeting D New system ID: 1 Comp ID: 1
2025-01-28 10:45:58.107 6832-6896 Mavsdk com.example.greeting D Component Autopilot (1) added.
2025-01-28 10:45:58.107 6832-6896 Mavsdk com.example.greeting W Vehicle type changed (new type: 2, old type: 0)
2025-01-28 10:45:58.107 6832-6896 Mavsdk com.example.greeting D Discovered 1 component(s)
2025-01-28 10:45:58.108 6832-6894 Mavsdk com.example.greeting I System discovered
2025-01-28 10:45:58.115 6832-6892 Mavsdk com.example.greeting I Server started
2025-01-28 10:45:58.115 6832-6892 Mavsdk com.example.greeting I Server set to listen on 0.0.0.0:35297
2025-01-28 10:45:58.115 6832-6892 MAVSDK-Server com.example.greeting D mavsdk_server is now running, listening on port 35297
2025-01-28 10:45:58.113 6832-6832 mavsdk-event-qu com.example.greeting W type=1400 audit(0.0:3935): avc: denied { read } for name="somaxconn" dev="proc" ino=496700 scontext=u:r:untrusted_app:s0:c190,c256,c512,c768 tcontext=u:object_r:proc_net:s0 tclass=file permissive=0 app=com.example.greeting
2025-01-28 10:45:58.115 6832-6892 MainActivity com.example.greeting D port is 35297
2025-01-28 10:45:58.118 6832-6892 MainActivity com.example.greeting I Server started
2025-01-28 10:45:58.128 6832-6892 System.err com.example.greeting W SLF4J(W): No SLF4J providers were found.
2025-01-28 10:45:58.128 6832-6892 System.err com.example.greeting W SLF4J(W): Defaulting to no-operation (NOP) logger implementation
2025-01-28 10:45:58.128 6832-6892 System.err com.example.greeting W SLF4J(W): See https://www.slf4j.org/codes.html#noProviders for further details.
2025-01-28 10:45:58.191 6832-6917 TrafficStats com.example.greeting D tagSocket(100) with statsTag=0xffffffff, statsUid=-1
2025-01-28 10:45:58.410 6832-6896 Mavsdk com.example.greeting D New system ID: 255 Comp ID: 230
2025-01-28 10:45:58.410 6832-6896 Mavsdk com.example.greeting D Component Unsupported component (230) added.
2025-01-28 10:45:58.410 6832-6896 Mavsdk com.example.greeting D Discovered 1 component(s)
2025-01-28 10:45:59.429 6832-6921 ProfileInstaller com.example.greeting D Installing profile for com.example.greeting
2025-01-28 10:46:07.967 6832-6877 EGL_emulation com.example.greeting D app_time_stats: avg=202.23ms min=1.90ms max=9099.12ms count=49

[JonasVautherin]

Yes. I tried both arm and disarm commands and they worked fine.

This sounds like mavlink messages sent by MAVSDK are received by the autopilot, but mavlink messages sent by the autopilot are not received by MAVSDK. Because you use a TCP connection, I don't think it would be a problem there (usually that happens with UDP) 🤔.

Are you sure that you don't have multiple clients competing on the connection? Not sure how Ardupilot implements TCP support. Did you make your tests when only MAVSDK and Ardupilot are running, and not pymavlink or QGC in parallel?

[rrajivram]

I'm sure about multiple clients. I do have mavproxy running (as part of sim_vehicle), but that is only listening on localhost on UDP. I confirmed in the SITL run that only one connection is active.

…

On Tue, Jan 28, 2025 at 10:59 AM Jonas Vautherin ***@***.***> wrote: Yes. I tried both arm and disarm commands and they worked fine. This sounds like mavlink messages sent by MAVSDK are received by the autopilot, but mavlink messages sent by the autopilot are not received by MAVSDK. Because you use a TCP connection, I don't think it would be a problem there (usually that happens with UDP) 🤔. Are you sure that you don't have multiple clients competing on the connection? Not sure how Ardupilot implements TCP support. Did you make your tests when only MAVSDK and Ardupilot are running, and not pymavlink or QGC in parallel? — Reply to this email directly, view it on GitHub <#2500 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/BIN4CD2WFZAXZQANLNPSHGL2M4ISRAVCNFSM6AAAAABV5ZWYS2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDMMJXHEZDINZZGM> . You are receiving this because you authored the thread.Message ID: ***@***.***>