We Keep Coding

Apple Watch stops transmitting gyroscope/accelometer data after a few minutes for unknown reason

I have created a watchOS app that fetches data from the accelerometer and gyroscope and sends it to a socket server. The server just prints the data on the console. The socket server is made in python. My app works fine for a few minutes but then stops working.
I tested by creating an iPhone app and it's working fine. The problem is with the apple watch app.
Can someone help me with this? I don't understand what's going on.
server.py
import socket
localIP = ""
localPort = 20001
bufferSize = 10240
msgFromServer = "Hello UDP Client"
bytesToSend = str.encode(msgFromServer)
# Create a datagram socket
UDPServerSocket = socket.socket(family=socket.AF_INET, type=socket.SOCK_DGRAM)
# Bind to address and ip
UDPServerSocket.bind((localIP, localPort))
print("UDP server up and listening")
# Listen for incoming datagrams
while(True):
bytesAddressPair = UDPServerSocket.recvfrom(bufferSize)
message = bytesAddressPair[0]
address = bytesAddressPair[1]
clientMsg = "Message from Client:{}".format(message)
clientIP = "Client IP Address:{}".format(address)
print(clientMsg)
print(clientIP)
# Sending a reply to client
UDPServerSocket.sendto(bytesToSend, address)
InterfaceController.swift
#IBOutlet weak var stopButton: WKInterfaceButton!
#IBOutlet weak var startButton: WKInterfaceButton!
var session = WKExtendedRuntimeSession()
private var host: NWEndpoint.Host = "172.16.105.162"
private var port: NWEndpoint.Port = 20001
private var updateTimeInterval: Double = 1/60
override func awake(withContext context: Any?) {
// Configure interface objects here.
// startButton.setHidden(false)
startButton.setEnabled(true) // // stopButton.setHidden(true)
stopButton.setEnabled(false)
setUPSession()
}
override func willActivate() {
// This method is called when watch view controller is about to be visible to user
print("ACTIVATE")
}
override func didDeactivate() {
// This method is called when watch view controller is no longer visible
print("DEACTIVATE")
}
#IBAction func actionStop() { // startButton.setHidden(false)
startButton.setEnabled(true) // // stopButton.setHidden(true)
stopButton.setEnabled(false)
self.stopSession()
// MotionDatafetcher.shared.startSession() //stopWorkoutSEssion() //stopFetch()
}
#IBAction func actionStart() { // startButton.setHidden(true)
startButton.setEnabled(false) // // stopButton.setHidden(false)
stopButton.setEnabled(true)
self.startSession()
// MotionDatafetcher.shared.startFetch()
//MotionDatafetcher.shared.stopSession() //startWorkoutSession() //startDeviceMotionFetch()
}
}
extension InterfaceController : WKExtendedRuntimeSessionDelegate{
func setUPSession() {
// Create the session object.
session = WKExtendedRuntimeSession()
// Assign the delegate.
session.delegate = self
MySocketManager.shared.setUpConn()
}
func startSession() {
session.start()
MySocketManager.shared.connectToUDP(host, port)
MotionDatafetcher.shared.startDeviceMotionFetch(updateTimeInterval)
}
func stopSession() {
session.invalidate()
MotionDatafetcher.shared.stopFetch()
MySocketManager.shared.cancelConnToUDP()
}
func extendedRuntimeSession(_ extendedRuntimeSession: WKExtendedRuntimeSession, didInvalidateWith reason: WKExtendedRuntimeSessionInvalidationReason, error: Error?) {
}
func extendedRuntimeSessionDidStart(_ extendedRuntimeSession: WKExtendedRuntimeSession) {
}
func extendedRuntimeSessionWillExpire(_ extendedRuntimeSession: WKExtendedRuntimeSession) {
self.stopSession()
}
}

.py file executed by C# process not waiting to finish

I want to run .py file from my C# project, and get the result. The python script is making an API request, and returns an auth_key token, which I want to use in my C# code. The only problem is that, for some reason the C# code doesn't wait for the process to finish, and thus that not every account has auth_key. Here is my C# code.
private static void GenerateTokens()
{
var url = ConfigurationManager.AppSetting[GeSettingsNode() + ":ip"];
for (int i = 0; i < accounts.Count; i++)
{
ProcessStartInfo start = new ProcessStartInfo();
start.FileName = ConfigurationManager.AppSetting["PythonPath"];
start.Arguments = string.Format($"python_operation_processor.py {accounts[i].client_key_id} {accounts[i].key_sercret_part} {url}");
start.UseShellExecute = false;
start.RedirectStandardOutput = true;
Process process = Process.Start(start);
using (StreamReader reader = process.StandardOutput)
{
accounts[i].auth_key = reader.ReadToEnd().Trim();
}
}
}
And here is my Python script ( python_operation_processor.py )that's making the API requests.
if __name__ == '__main__':
client_key_id = sys.argv[1]
client_secret = sys.argv[2]
API_URL = sys.argv[3]
nonce = str(uuid.uuid4())
d = datetime.datetime.now() - datetime.timedelta(hours=3)
timestamp = d.strftime('%Y-%m-%dT%H:%M:%S.%f')[:-3] + 'Z'
signature = b64encode(hmac.new(b64decode(client_secret), msg=bytes(client_key_id + nonce + timestamp, 'utf-8'),
digestmod=hashlib.sha256).digest()).decode('utf-8')
r = requests.post(API_URL + '/v1/authenticate',
json={'client_key_id': client_key_id, 'timestamp': timestamp, 'nonce': nonce,
'signature': signature})
if r.status_code != 200:
raise Exception('Failed to authenticate: ' + r.text)
auth_token = r.json()['token']
print(auth_token)
Do you have any idea, how I can wait for the execution of every process, and get the token for every account ?

I recently created something similar and ended up with this because, whilst waiting for the process is easy, it is tricky to get the output stream filled correctly.
The method presented also allow you to display the output into a textblock or similar in your application.
If you use it like this, the token will be written to the StringBuilder, and used as return value.
private async Task<string> RunCommand(string fileName, string args)
{
var timeoutSignal = new CancellationTokenSource(TimeSpan.FromMinutes(3));
ProcessStartInfo start = new ProcessStartInfo();
start.FileName = fileName;
start.Arguments = string.Format("{0}", args);
start.RedirectStandardOutput = true;
start.RedirectStandardError = true;
start.UseShellExecute = false;
start.CreateNoWindow = true;
var sb = new StringBuilder();
using (Process process = new Process())
{
process.StartInfo = start;
process.OutputDataReceived += (sender, eventArgs) =>
{
sb.AppendLine(eventArgs.Data); //allow other stuff as well
};
process.ErrorDataReceived += (sender, eventArgs) => {};
if (process.Start())
{
process.EnableRaisingEvents = true;
process.BeginOutputReadLine();
process.BeginErrorReadLine();
await process.WaitForExitAsync(timeoutSignal.Token);
//allow std out to be flushed
await Task.Delay(100);
}
}
return sb.ToString();
}
To render this to a textblock in a UI application, you'll need to:
implement an event which signals a new line has been read, which means forwarding the process.OutputDataReceived event.
if your thinking about a live feed, make sure you flush the stdio buffer in python setting flush to true: print(""hello world"", flush=True)
If you're using an older .net version; you can implement the WaitForExitAsync as described here: https://stackoverflow.com/a/17936541/2416958 as an extention method:
public static class ProcessHelpers
{
public static Task<bool> WaitForExitAsync(this Process process, TimeSpan timeout)
{
ManualResetEvent processWaitObject = new ManualResetEvent(false);
processWaitObject.SafeWaitHandle = new SafeWaitHandle(process.Handle, false);
TaskCompletionSource<bool> tcs = new TaskCompletionSource<bool>();
RegisteredWaitHandle registeredProcessWaitHandle = null;
registeredProcessWaitHandle = ThreadPool.RegisterWaitForSingleObject(
processWaitObject,
delegate(object state, bool timedOut)
{
if (!timedOut)
{
registeredProcessWaitHandle.Unregister(null);
}
processWaitObject.Dispose();
tcs.SetResult(!timedOut);
},
null /* state */,
timeout,
true /* executeOnlyOnce */);
return tcs.Task;
}
}

why is C# getting a distorted image from a python server?

I'm trying to transfer camera stream from my raspberry pi to pc as fast as possible. Now I'm trying to transfer it using MJPEG method. So I have a python script on my raspberry as server:
import io
import socket
import struct
import time
import cv2
class SplitFrames(object):
def __init__(self, connection):
self.connection = connection
self.stream = io.BytesIO()
self.count = 0
def write(self, buf):
if buf.startswith(b'\xff\xd8'):
# Start of new frame; send the old one's length
# then the data
size = self.stream.tell()
if size > 0:
self.connection.write(struct.pack('<L', size))
self.connection.flush()
self.stream.seek(0)
self.connection.write(self.stream.read(size))
self.count += 1
self.stream.seek(0)
self.stream.write(buf)
server_socket = socket.socket()
server_socket.bind(('0.0.0.0', 8001))
server_socket.listen(0)
# Accept a single connection and make a file-like object out of it
connection = server_socket.accept()[0].makefile('wb')
try:
output = SplitFrames(connection)
time.sleep(2)
cap = cv2.VideoCapture(0)
while True:
ret, img = cap.read()
ret, jpg = cv2.imencode('.jpg', img)
output.write(jpg.tostring())
connection.write(struct.pack('<L', 0))
finally:
connection.close()
server_socket.close()
that works well. Also I have a python script on my pc as client, that also works well and I receive a good stream:
import io
import socket
import struct
from PIL import Image
import cv2
import numpy as np
# Start a socket listening for connections on 0.0.0.0:8000 (0.0.0.0 means
# all interfaces)
client_socket = socket.socket()
client_socket.connect(("10.12.34.2", 8001))
connection = client_socket.makefile('rb')
try:
while True:
# Read the length of the image as a 32-bit unsigned int. If the
# length is zero, quit the loop
a = connection.read(struct.calcsize('<L'))
image_len = struct.unpack('<L', a)[0]
if not image_len:
break
# Construct a stream to hold the image data and read the image
# data from the connection
image_stream = io.BytesIO()
image_stream.write(connection.read(image_len))
# Rewind the stream, open it as an image with PIL and do some
# processing on it
image_stream.seek(0)
image = Image.open(image_stream)
cv_image = np.array(image)
cv2.imshow('Stream',cv_image)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
finally:
connection.close()
client_socket.close()
But I needed to write client side on WPF, so I wrote it, but it doesn't work well. I receive distorted stream and after a few seconds WPF app breaks and gives me System.IO.FileFormatException. Here is the image from WPF:
What could be the reason of this? Thanks for any advice!
Here is the minimum reproducible code:
C#
using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Net;
using System.Net.Sockets;
using System.Threading;
using System.Windows;
using System.Windows.Media.Imaging;
namespace WPFTest
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class MainWindow : Window
{
private static bool connected = false;
private Socket sct;
private IPEndPoint ipPoint;
// TCP
private bool stopThread = false;
private Thread thread;
public MainWindow()
{
InitializeComponent();
}
private void ConnectButton_Click(object sender, RoutedEventArgs e)
{
if (!connected)
{
try
{
//this.ipPoint = new IPEndPoint(IPAddress.Parse("127.0.0.1"), int.Parse("8001", CultureInfo.InvariantCulture));
this.ipPoint = new IPEndPoint(IPAddress.Parse("10.12.34.2"), int.Parse("8001", CultureInfo.InvariantCulture));
}
catch (Exception error)
{
return;
}
this.sct = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP);
stopThread = false;
thread = new Thread(() => { Listening(); });
thread.IsBackground = false;
thread.Start();
connected = true;
}
}
private void DisconnectButton_Click(object sender, RoutedEventArgs e)
{
if (connected)
{
StopListening();
connected = false;
}
}
private void Listening()
{
try
{
sct.Connect(ipPoint);
}
catch (Exception e)
{
StopListening();
connected = false;
return;
}
Thread.Sleep(1000);
try
{
while (!this.stopThread)
{
byte[] data = GetInputBytes(sct);
Application.Current.Dispatcher.Invoke(() =>
{
SetImage(data);
});
}
sct.Shutdown(SocketShutdown.Both);
sct.Close();
}
catch (Exception e)
{
StopListening();
}
}
public void StopListening()
{
this.stopThread = true;
try
{
thread.Abort();
sct.Shutdown(SocketShutdown.Both);
sct.Close();
}
catch (Exception e)
{
//
}
}
private void SetImage(byte[] array)
{
var image = new BitmapImage();
using (var mem = new MemoryStream(array))
{
mem.Position = 0;
image.BeginInit();
image.CreateOptions = BitmapCreateOptions.PreservePixelFormat;
image.CacheOption = BitmapCacheOption.OnLoad;
image.UriSource = null;
image.StreamSource = mem;
image.EndInit();
}
image.Freeze();
ImageCamera.Source = image;
}
public static byte[] GetInputBytes(Socket clientSocket)
{
byte[] rcvLenBytes = new byte[4];
clientSocket.Receive(rcvLenBytes);
UInt32 rcvLen = BytesToInt(rcvLenBytes);
byte[] rcvBytes;
byte[] clientData;
List<byte> rcvBytesList = new List<byte>();
int totalBytes = 0;
while (totalBytes < rcvLen)
{
if (rcvLen - totalBytes < 262144)
{
clientData = new byte[rcvLen - totalBytes];
}
else
{
clientData = new byte[262144];
}
int bytesReceived = clientSocket.Receive(clientData);
rcvBytesList.AddRange(clientData);
totalBytes += bytesReceived;
}
rcvBytes = rcvBytesList.ToArray();
return rcvBytes;
}
public static UInt32 BytesToInt(byte[] arr)
{
UInt32 wd = ((UInt32)arr[3] << 24) | ((UInt32)arr[2] << 16) | ((UInt32)arr[1] << 8) | (UInt32)arr[0];
return wd;
}
}
}
XAML
<Window x:Class="WPFTest.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:WPFTest"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="*"></RowDefinition>
<RowDefinition Height="*"></RowDefinition>
<RowDefinition Height="200px"></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" ></ColumnDefinition>
<ColumnDefinition Width="220px" ></ColumnDefinition>
<ColumnDefinition Width="*" ></ColumnDefinition>
<ColumnDefinition Width="180px" ></ColumnDefinition>
</Grid.ColumnDefinitions>
<Button Grid.Column="2" Grid.Row="3" Height="60" Width="140" Content="Connect" x:Name="ConnectButton" FontSize="20" FontFamily="LilyUPC" FontWeight="Bold" HorizontalAlignment="Left" VerticalAlignment="Top" Margin="20, 80, 20, 0" Click="ConnectButton_Click"/>
<Button Grid.Column="0" Grid.Row="3" Height="60" Width="140" Content="Disconnect" x:Name="DisconnectButton" FontSize="20" FontFamily="LilyUPC" FontWeight="Bold" HorizontalAlignment="Right" VerticalAlignment="Top" Margin="20, 80, 20, 0" Click="DisconnectButton_Click"/>
<Image Grid.Column="0" Grid.Row="0" Grid.RowSpan="2" Grid.ColumnSpan="3" Margin="10" RenderOptions.BitmapScalingMode="NearestNeighbor" RenderOptions.EdgeMode="Aliased" x:Name="ImageCamera"></Image>
</Grid>
</Window>

Thanks to #ThomasWeller for their answer in comments! As they said:
AddRange adds the whole buffer. How should it know how many bytes were received?
So I rewrote my receive method like this:
public static byte[] GetInputBytes(Socket clientSocket)
{
byte[] rcvLenBytes = new byte[4];
clientSocket.Receive(rcvLenBytes);
UInt32 rcvLen = BytesToInt(rcvLenBytes);
byte[] rcvBytes;
byte[] clientData;
List<byte> rcvBytesList = new List<byte>();
int totalBytes = 0;
while (totalBytes < rcvLen)
{
if (rcvLen - totalBytes < 262144)
{
clientData = new byte[rcvLen - totalBytes];
}
else
{
clientData = new byte[262144];
}
int bytesReceived = clientSocket.Receive(clientData);
rcvBytesList.AddRange(clientData.Take(bytesReceived).ToArray());
totalBytes += bytesReceived;
}
rcvBytes = rcvBytesList.ToArray();
return rcvBytes;
}
Changed line is: rcvBytesList.AddRange(clientData.Take(bytesReceived).ToArray());
It works fine now.

Connecting to multiple ESP32 Ble servers lowers datarate

I have an issue with connecting to multiple esp32 ble servers.
Each esp32 does the following:
Declare a Service and 2 Characteristics with Notify property
Set the value to characteristics (max 20 bytes in size)
When a client is connected start notifying.
On my PC side I'm using Python3 with bluepy to communicate to one or more esp32 devices.
If i connect only to one device I can receive data at about 250 Hz for Characteristic 1 and 100 Hz for Characteristic 2.
The problem arises when I connect to two or more devices. In this case only one device transmits at the rate mentioned above and all the other devices transmit very slowly, some may fall below 10 Hz.
Code for ESP32
publishBLEdata() is used to send a 20-byte array.
#include <BLEDevice.h>
#include <BLEServer.h>
#include <BLEUtils.h>
#include <BLE2902.h>
#include "esp_bt_main.h"
#include "esp_bt_device.h"
BLEServer *pServer = NULL;
BLECharacteristic * p_TX_FSR_Characteristic;
BLECharacteristic * p_TX_IMU_Characteristic;
bool deviceConnected = false;
bool oldDeviceConnected = false;
#define SERVICE_UUID "42426001-0bfe-4adb-aefb-5b5708b77691" // UART service UUID
#define CHARACTERISTIC_UUID_TX_FSR "42426002-0bfe-4adb-aefb-5b5708b77691"
#define CHARACTERISTIC_UUID_TX_IMU "42426003-0bfe-4adb-aefb-5b5708b77691"
#define BLE_MAX_DATA_SIZE 20
class MyServerCallbacks: public BLEServerCallbacks {
void onConnect(BLEServer* pServer) {
deviceConnected = true;
};
void onDisconnect(BLEServer* pServer) {
deviceConnected = false;
}
};
bool initBluetooth()
{
if (!btStart()) {
Serial.println("Failed to initialize controller");
return false;
}
if (esp_bluedroid_init() != ESP_OK) {
Serial.println("Failed to initialize bluedroid");
return false;
}
if (esp_bluedroid_enable() != ESP_OK) {
Serial.println("Failed to enable bluedroid");
return false;
}
}
void initBLEService() {
Serial.begin(115200);
initBluetooth();
const uint8_t* point = esp_bt_dev_get_address();
// Set device name to containe the last 2 values of the MAC address
char bt_name[13] = {};
sprintf(bt_name, "ESP32_%02X%02X", (int)point[4], (int)point[5]);
// Create the BLE Device
BLEDevice::init(bt_name);
// Create the BLE Server
pServer = BLEDevice::createServer();
pServer->setCallbacks(new MyServerCallbacks());
// Create the BLE Service
BLEService *pService = pServer->createService(SERVICE_UUID);
// Create a BLE Characteristics
p_TX_FSR_Characteristic = pService->createCharacteristic(
CHARACTERISTIC_UUID_TX_FSR,
BLECharacteristic::PROPERTY_NOTIFY
);
p_TX_IMU_Characteristic = pService->createCharacteristic(
CHARACTERISTIC_UUID_TX_IMU,
BLECharacteristic::PROPERTY_NOTIFY
);
p_TX_FSR_Characteristic->addDescriptor(new BLE2902());
p_TX_IMU_Characteristic->addDescriptor(new BLE2902());
// Start the service
pService->start();
BLEAdvertising *pAdvertising = BLEDevice::getAdvertising();
pAdvertising->addServiceUUID(SERVICE_UUID);
pAdvertising->setScanResponse(true);
pAdvertising->setMinPreferred(0x06); // functions that help with iPhone connections issue
pAdvertising->setMinPreferred(0x12);
BLEDevice::startAdvertising();
Serial.print(bt_name);
Serial.println("\t Waiting a client connection to notify...");
}
void publishBLEdata(uint8_t* txValue, size_t length, char mode, uint16_t delay_ns = 3300)
{
BLECharacteristic * characteristic;
switch (mode)
{
case 'f':
characteristic = p_TX_FSR_Characteristic;
break;
case 'i':
characteristic = p_TX_IMU_Characteristic;
break;
default:
characteristic = p_TX_FSR_Characteristic;
break;
}
if (deviceConnected) {
characteristic->setValue(txValue, length);
characteristic->notify();
delayMicroseconds(delay_ns);
}
// disconnecting
if (!deviceConnected && oldDeviceConnected) {
delay(500); // give the bluetooth stack the chance to get things ready
pServer->startAdvertising(); // restart advertising
Serial.println("start advertising");
oldDeviceConnected = deviceConnected;
}
// connecting
if (deviceConnected && !oldDeviceConnected) {
// do stuff here on connecting
oldDeviceConnected = deviceConnected;
}
}
Python code
Connect to a specific MAC address, and for every notification activate the callback function which unpacks and displays the data. For every new esp32 device that I want to connect I run a separate python script.
#!/usr/bin/env python3
from bluepy import btle
class MyDelegate(btle.DefaultDelegate):
def __init__(self, handle_fsr, handle_imu):
btle.DefaultDelegate.__init__(self)
self.handle_fsr = handle_fsr
self.handle_imu = handle_imu
self.fsr_datatype = 'B' # 1 byte unsigned char
self.fsr_num_bytes = 1
self.fsr_num_values = 8
self.imu_datatype = 'h' # 2 byte integer
self.imu_num_bytes = 2
self.imu_num_values = 10
def handleNotification(self, cHandle, data):
if cHandle == self.handle_fsr:
fsr_decoded = list()
for i in range(self.fsr_num_values):
data_raw = data[(i*self.fsr_num_bytes):(self.fsr_num_bytes + i*self.fsr_num_bytes)]
val, = struct.unpack(self.fsr_datatype, data_raw)
fsr_decoded.append(val)
print(fsr_msg)
if cHandle == self.handle_imu:
imu_decoded = list()
imu_msg = IMU()
for i in range(self.imu_num_values):
data_raw = data[(i*self.imu_num_bytes):(self.imu_num_bytes + i*self.imu_num_bytes)]
val, = struct.unpack(self.imu_datatype, data_raw)
imu_decoded.append(val)
print(imu_decoded)
mac_addr = "xx:xx:xx:xx:xx:xx"
service_uuid = btle.UUID("42426001-0bfe-4adb-aefb-5b5708b77691")
fsr_uuid = btle.UUID("42426002-0bfe-4adb-aefb-5b5708b77691")
imu_uuid = btle.UUID("42426003-0bfe-4adb-aefb-5b5708b77691")
try:
p = btle.Peripheral(mac_addr)
ch_fsr = p.getCharacteristics(uuid=fsr_uuid)[0]
ch_imu = p.getCharacteristics(uuid=imu_uuid)[0]
handle_fsr = ch_fsr.getHandle()
handle_imu = ch_imu.getHandle()
# Enable notifications
p.writeCharacteristic(handle_fsr+1, b"\x01\x00")
p.writeCharacteristic(handle_imu+1, b"\x01\x00")
p.setDelegate( MyDelegate(handle_fsr, handle_imu) )
except Exception as e:
raise e
run = True
while run:
try:
if p.waitForNotifications(1.0):
# handleNotification() was called
continue
print("{} Waiting...".format(namespace))
except KeyboardInterrupt:
run = False
p.disconnect()
And that's about it.
Can anyone please help me figure out what I'm missing?
Are there any advertising parameters missing on the server such that multiple devices don't interfere with each other? Or maybe there's something missing in the Python script (client side).
Thanks in advance.

C++ GUI freezes during communication over socket thread with Python

First of all I want to mention that I've gone through a lot of socket threading tutorials before attempting to integrate it into my own GUI, but I still consider myself fairly new to the subject.
I have a server written in python that opens a socket and starts a thread over localhost, and listens over the port for a client:
def StartThread():
tcpsock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
tcpsock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
tcpsock.bind((TCP_IP, TCP_PORT))
threads = []
tcpsock.listen(5)
print "Waiting for incoming connections from client..."
(conn, (ip,port)) = tcpsock.accept()
print 'Got connection from ', (ip,port)
newthread = ClientThread(ip,port,conn, 1)
newthread.start()
return newthread
Here is the ClientThread class:
class ClientThread(Thread):
def __init__(self,ip,port,sock, status):
Thread.__init__(self)
self.ip = ip
self.port = port
self.sock = sock
self.status = 1
print " New thread started for "+ip+":"+str(port)
After I run the server code, I click a button on my C++ GUI which runs the client code StartConnection() based off the Microsoft Winsock client template.
void CPSR_CRSDlg::OnBnClickedInit2()
{
if(!checkTimerStarted())
// Set mmtimer to aquire the data
{
m_ntimerID = timeSetEvent( TIMERINTRRVAL,
1,
timerHandler,
0,
TIME_PERIODIC);
SetTimer(1,TIMERINTRRVAL_2,NULL);
m_bTimer_started = true;
}
StartConnection();
}
The connection does start successfully and the python code prints the address of the connection and the thread, but then my GUI freezes, so that I can't click any of the other buttons to actually send data over the connection.
Why does my application freeze? Am I not instantiating the thread correctly?
The StartConnection() code is off the msdn website but here is my slightly modified version if needed:
void StartConnection(){
//printf("Connection Starting... \n");
WSADATA wsaData;
ConnectSocket = INVALID_SOCKET;
struct addrinfo *result = NULL,
*ptr = NULL,
hints;
int argc = 2;
// Validate the parameters
if (argc != 2) {
printf("usage: %s server-name\n", "client");
return;
}
// Initialize Winsock
iResult = WSAStartup(MAKEWORD(2,2), &wsaData);
if (iResult != 0) {
printf("WSAStartup failed with error: %d\n", iResult);
return;
}
ZeroMemory( &hints, sizeof(hints) );
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = IPPROTO_TCP;
// Resolve the server address and port
//iResult = getaddrinfo(argv[1], DEFAULT_PORT, &hints, &result);
iResult = getaddrinfo("localhost", DEFAULT_PORT, &hints, &result);
if ( iResult != 0 ) {
printf("getaddrinfo failed with error: %d\n", iResult);
WSACleanup();
return;
}
// Attempt to connect to an address until one succeeds
for(ptr=result; ptr != NULL ;ptr=ptr->ai_next) {
// Create a SOCKET for connecting to server
ConnectSocket = socket(ptr->ai_family, ptr->ai_socktype,
ptr->ai_protocol);
if (ConnectSocket == INVALID_SOCKET) {
printf("socket failed with error: %ld\n", WSAGetLastError());
WSACleanup();
return;
}
// Connect to server.
iResult = connect( ConnectSocket, ptr->ai_addr, (int)ptr->ai_addrlen);
if (iResult == SOCKET_ERROR) {
closesocket(ConnectSocket);
ConnectSocket = INVALID_SOCKET;
continue;
}
break;
}
freeaddrinfo(result);
if (ConnectSocket == INVALID_SOCKET) {
printf("Unable to connect to server!\n");
WSACleanup();
return;
}
return;
}
void StopConnection(){
closesocket(ConnectSocket);
WSACleanup();
return;
}
void SendJointValues(double *joints){
iResult = recv(ConnectSocket, recvbuf, recvbuflen, 0);
j = parseJSON(joints[0],joints[1],joints[2],joints[3], \
joints[4],joints[5]);
int x = send(ConnectSocket, j, strlen(j), 0);
//iResult = recv(ConnectSocket, recvbuf, recvbuflen, 0);
}
Edit:
The GUI does respond again after I send data via the server, and the client then successfully sends back one iteration of data. But after this exchange the GUI freezes again until more data is sent.
Here is the send+receive portion of the server:
def receiveData(self):
while (self.status == 1):
joints = [0,0,0,0,0,0]
self.sock.sendall('send')
print "Data Sent!"
data = self.sock.recv(4096)
print "Data received: ", data
self.checkStatus(data)
print "Status is: ", self.status
if (self.status == 1):
data_loaded = json.loads(data)
joints = self.createJointArr(data_loaded['Joints'])
time.sleep(0.5)
print joints
return joints
And the SendJointValues() in the client is called in this Timer function:
void CPSR_CRSDlg::OnTimer(UINT_PTR nIDEvent)
{
CString str;
long Position;
double engPosition;
double dblPosition;
double dblSpeed;
bool ret;
// Arch
USB4_01.Controller_3.getEncoderPosition(Position);
countTodegree(Position,engPosition,ARCH);
str.Format(_T("%10.2f"),engPosition);
m_staPosArch.SetWindowText(str);
// Wrist Pitch
USB4_01.Controller_2.getEncoderPosition(Position);
countTodegree(Position,engPosition,TILT);
str.Format(_T("%10.2f"),engPosition);
m_staPosPitch.SetWindowText(str);
// Linear
USB4_02.Controller_1.getEncoderPosition(Position);
countTodegree(Position,engPosition,LINEAR);
str.Format(_T("%10.2f"),engPosition);
m_staPosLinear.SetWindowText(str);
// Turret
USB4_02.Controller_2.getEncoderPosition(Position);
countTodegree(Position,engPosition,TURRET);
str.Format(_T("%10.2f"),engPosition);
m_staPosTurret.SetWindowText(str);
// Roll
USB4_02.Controller_4.getEncoderPosition(Position);
countTodegree(Position,engPosition,ROLL);
str.Format(_T("%10.2f"),engPosition);
m_staPosRoll.SetWindowText(str);
// Drill/Tool
USB4_02.Controller_3.getEncoderPosition(Position);
countTodegree(-Position,engPosition,DRILL);
str.Format(_T("%10.2f"),engPosition);
m_staPosDrill.SetWindowText(str);
// For Penetrate joint
if(JntPenetration.isInitialized())
{
// Get Position feedback
ret = JntPenetration.getPosition(dblPosition);
if(ret) // get position feedback successfully
{
Position = (long) dblPosition;
countTodegree(Position,engPosition,PENETRATE);
str.Format(_T("%10.2f"),engPosition);
m_staPosPenetrate.SetWindowText(str);
m_dCurentPentrationPosition = engPosition;
}
// Get Speed feedback;
if(m_bDrilling_started)
{
// Penetration position close enough AND At least on cycle reached
if( (abs(engPosition - m_dDrilling_target_position) < 0.1) &&(m_Direction_Changed == true))
m_bPenetrationStopped = true;
else
m_bPenetrationStopped = false;
//JntPenetration.getSpeed(dblSpeed);
//if(dblSpeed < .05 )
// m_bPenetrationStopped = true;
//else
// m_bPenetrationStopped = false;
}
}
SendJointValues(JointArray);
// For drilling motion control
if(m_bDrilling_started)
drilingProcedure();
CDialog::OnTimer(nIDEvent);
}