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Windows IOT UWP - Relay

Good Evening,
I’m doing some troubleshooting on the beginning of my home automation system. I am trying to toggle a relay using a Raspberry PI 3 and Windows IOT in C#. I’ve been playing with the code and I can see the relay toggle once or twice, but then the app crashes. I’m an IOT Noob, so is there something wrong with this code? (Variable names are defined elsewhere and the weird variable names I have below are for my WIP project... I prefer troubleshooting in English)....
private void BtnTempFan_Click(object sender, RoutedEventArgs e)
{
if (BtnTempFan.IsChecked == true)
{
TogglePin(TempFan, TempFan_PIN, BtnTempFan, GpioPinValue.High);
}
else
{
TempFan.Dispose();
}
}
private void TogglePin(GpioPin PinName, int PinNumber, ToggleButton Name, GpioPinValue value)
{
int pinnumber = PinNumber;
GpioPinValue pinvalue;
var gpio = GpioController.GetDefault();
PinName = gpio.OpenPin(pinnumber);
if (gpio == null)
{
PinName = null;
LblError.Text = "We can't find the controller on the device" + PinName;
LblError.Visibility = Visibility.Visible;
return;
}
if (PinName == null)
{
LblError.Text = "We can't find the pin on the device. Pin number " + PinNumber + "does not exist";
LblError.Visibility = Visibility.Visible;
return;
}
if (Name.IsChecked == true)
{
pinvalue = value;
PinName.Write(pinvalue);
PinName.SetDriveMode(GpioPinDriveMode.Output);
}

You don't say what the exception is. However, I believe you are supposed open a GPIO pin only once per app:
var gpio = GpioController.GetDefault();
PinName = gpio.OpenPin(pinnumber);
You have it in a method which is called once per button click. By opening the pin more than once, you are encountering that the pin is already open, and I believe this is what throws an exception and crashes the app.
In my code, I handle pin states in a "driver" class, and have a method called Connect which I call once when starting the application. For example:
public async Task Connect()
{
var gpioController = await GpioController.GetDefaultAsync();
try
{
_openPin = gpioController.OpenPin(_doorMotorOpenPin);
_closePin = gpioController.OpenPin(_doorMotorClosePin);
}
}
This encapsulates the 2 pins: _openPin and _closePin into a class that I can manage the lifecycle of.

Codekaizen is correct. I separated out opening the pin into a method that only gets called once and problem solved.
private void BtnTempFan_Click(object sender, RoutedEventArgs e)
{
if (BtnTempFan.IsChecked == false)
{
TogglePin(TempFan, TempFan_PIN, BtnTempFan, GpioPinValue.High);
}
if (BtnTempFan.IsChecked == true)
{
TogglePin(TempFan, TempFan_PIN, BtnTempFan, GpioPinValue.Low);
}
}
private void InitializePins()
{
var gpio = GpioController.GetDefault();
// Show an error if there is no GPIO controller
if (gpio == null)
{
TempFan = null;
LblError.Text = "We can't find the controller on the device";
LblError.Visibility = Visibility.Visible;
return;
}
TempFan = gpio.OpenPin(TempFan_PIN);
TempFan.SetDriveMode(GpioPinDriveMode.Output);
}
private void TogglePin(GpioPin PinName, int PinNumber, ToggleButton Name, GpioPinValue value)
{
int pinnumber = PinNumber;
GpioPinValue pinvalue;
pinvalue = value;
PinName.Write(pinvalue);
}

Single instance dotnetcore cli app on linux

I am interested in how to inforce a single instance policy for dotnetcore console apps. To my surprise it seems like there isn't much out there on the topic. I found this one stacko, How to restrict a program to a single instance, but it doesnt seem to work for me on dotnetcore with ubuntu. Anyone here do this before?

Variation of #MusuNaji's solution at: How to restrict a program to a single instance
private static bool AlreadyRunning()
{
Process[] processes = Process.GetProcesses();
Process currentProc = Process.GetCurrentProcess();
logger.LogDebug("Current proccess: {0}", currentProc.ProcessName);
foreach (Process process in processes)
{
if (currentProc.ProcessName == process.ProcessName && currentProc.Id != process.Id)
{
logger.LogInformation("Another instance of this process is already running: {pid}", process.Id);
return true;
}
}
return false;
}

This is a little more difficult on .NET core than it should be, due to the problem of mutex checking on Linux/MacOS (as reported above). Also Theyouthis's solution isn't helpful as all .NET core apps are run via the CLI which has a process name of 'dotnet' which if you are running multiple .NET core apps on the same machine the duplicate instance check will trigger incorrectly.
A simple way to do this that is also multi-platform robust is to open a file for write when the application starts, and close it at the end. If the file fails to open it is due to another instance running concurrently and you can handle that in the try/catch. Using FileStream to open the file will also create it if it doesn't first exist.
try
{
lockFile = File.OpenWrite("SingleInstance.lck");
}
catch (Exception)
{
Console.WriteLine("ERROR - Server is already running. End that instance before re-running. Exiting in 5 seconds...");
System.Threading.Thread.Sleep(5000);
return;
}

Here is my implementation using Named pipes. It supports passing arguments from the second instance.
Note: I did not test on Linux or Mac but it should work in theory.
Usage
public static int Main(string[] args)
{
instanceManager = new SingleInstanceManager("8A3B7DE2-6AB4-4983-BBC0-DF985AB56703");
if (!instanceManager.Start())
{
return 0; // exit, if same app is running
}
instanceManager.SecondInstanceLaunched += InstanceManager_SecondInstanceLaunched;
// Initialize app. Below is an example in WPF.
app = new App();
app.InitializeComponent();
return app.Run();
}
private static void InstanceManager_SecondInstanceLaunched(object sender, SecondInstanceLaunchedEventArgs e)
{
app.Dispatcher.Invoke(() => new MainWindow().Show());
}
Your Copy-and-paste code
public class SingleInstanceManager
{
private readonly string applicationId;
public SingleInstanceManager(string applicationId)
{
this.applicationId = applicationId;
}
/// <summary>
/// Detect if this is the first instance. If it is, start a named pipe server to listen for subsequent instances. Otherwise, send <see cref="Environment.GetCommandLineArgs()"/> to the first instance.
/// </summary>
/// <returns>True if this is tthe first instance. Otherwise, false.</returns>
public bool Start()
{
using var client = new NamedPipeClientStream(applicationId);
try
{
client.Connect(0);
}
catch (TimeoutException)
{
Task.Run(() => StartListeningServer());
return true;
}
var args = Environment.GetCommandLineArgs();
using (var writer = new BinaryWriter(client, Encoding.UTF8))
{
writer.Write(args.Length);
for (int i = 0; i < args.Length; i++)
{
writer.Write(args[i]);
}
}
return false;
}
private void StartListeningServer()
{
var server = new NamedPipeServerStream(applicationId);
server.WaitForConnection();
using (var reader = new BinaryReader(server, Encoding.UTF8))
{
var argc = reader.ReadInt32();
var args = new string[argc];
for (int i = 0; i < argc; i++)
{
args[i] = reader.ReadString();
}
SecondInstanceLaunched?.Invoke(this, new SecondInstanceLaunchedEventArgs { Arguments = args });
}
StartListeningServer();
}
public event EventHandler<SecondInstanceLaunchedEventArgs> SecondInstanceLaunched;
}
public class SecondInstanceLaunchedEventArgs
{
public string[] Arguments { get; set; }
}
Unit test
[TestClass]
public class SingleInstanceManagerTests
{
[TestMethod]
public void SingleInstanceManagerTest()
{
var id = Guid.NewGuid().ToString();
var manager = new SingleInstanceManager(id);
string[] receivedArguments = null;
var correctArgCount = Environment.GetCommandLineArgs().Length;
manager.SecondInstanceLaunched += (sender, e) => receivedArguments = e.Arguments;
var instance1 = manager.Start();
Thread.Sleep(200);
var manager2 = new SingleInstanceManager(id);
Assert.IsFalse(manager2.Start());
Thread.Sleep(200);
Assert.IsTrue(instance1);
Assert.IsNotNull(receivedArguments);
Assert.AreEqual(correctArgCount, receivedArguments.Length);
var receivedArguments2 = receivedArguments;
var manager3 = new SingleInstanceManager(id);
Thread.Sleep(200);
Assert.IsFalse(manager3.Start());
Assert.AreNotSame(receivedArguments, receivedArguments2);
Assert.AreEqual(correctArgCount, receivedArguments.Length);
}
}

The downside of deandob's solution is that one can launch the application from another path. So you may prefer some static path or a tmp path for all users.
Here is my attempt:
//second instance launch guard
var tempPath = Environment.GetEnvironmentVariable("TEMP", EnvironmentVariableTarget.Machine)
??
Path.GetTempPath();
var lockPath = Path.Combine(tempPath, "SingleInstance.lock");
await using var lockFile = File.OpenWrite(lockPath);
here I'm trying to get TEMP system variable at the scope of machine (not the user TEMP) and if its empty - fallback to the user's temp folder on windows or shared /tmp on some linuxes.

c# outlook addin userproperty of first item in collection not found

Outlook 2016
.Net Framework 4.5
i encounter a really strange behaviour:
when i iterate through the items collection of a contact folder in some very special undefined cases (which i do not really understand) some userproperties of the first item of the collection fail to load. However the UserProperties are definitly set.
The approach is following:
I open the contact folder (to which the items will be moved) in outlook.
then i execute the "test"
the execution of the test can be suammrized as following:
click button ->
start thread
iterate through the items (on first iteration no items are present).
add new items{
create item
set userproperty PRE before item is initially saved
save item
move item to desired folder
set userproperty POST after item is moved
save item
}
end thread
click button ->
start thread
iterate through the items (here the userproperty POST sometimes fails to load on the first item of the collection, however when i investigate it, it IS there. It only fails for the first item and succeeds for every other following item).
...END
it seems to me that outlook somehow fails to update the userproperty definitions timely. But note that the first BackgroundWorker thread is already finished when iterating through the items with the second backgroundworker thread.
The problem could be related to the fact that iam viewing the folder in the explorer while the items are added and iterated.
This bug is hard to reproduce and does only occur rarely.
however i'm really missing insight into the inner workings of outlook so i can only speculate.
Idea for workarounds:
I could add an item with all userproperties before moving it. the problem here is that i need to add new userproperties, after the item is initially saved and moved to the folder, in some scenarios.
in few cases the userproperty key is dynamically created (with a pattern) so it wouldn't be optimal to predefine all userproperties.
It's very important that the userProperties are reliably loaded because some important features are based upon them.
Does anybody has a clue how the problem is caused and how to solve it? because this behaviour is driving me crazy.
some Code (not the original but it should contain all the relevant aspects)
//Ribbon
TestNS.TestCaller testCaller;
string folderID = "00000000BDB409934ED327439481EB6E1E1CC4D3010055B62301B58E32478DCD8C0D3FA6304600002C4CA4400000";
public void testButton0_Action(Office.IRibbonControl control)
{
if(testCaller == null){
testCaller = new TestNS.TestCaller(ThisAddIn.Outlook,folderID);
}
testCaller.Run();
}
//Ribbon end
using System.Runtime.InteropServices;
using Outlook = Microsoft.Office.Interop.Outlook;
using System.Diagnostics;
using System.Windows.Forms;
using System.ComponentModel;
namespace TestNS
{
public class TestCaller{
private Outlook.Application application;
private BackgroundWorker worker = new BackgroundWorker();
private Test test = null;
private string folderId;
private bool init = true;
private bool busy = false;
public TestCaller(Outlook.Application application, string folderId){
this.application = application;
this.folderId = folderId;
worker.DoWork += new DoWorkEventHandler(DoWork);
worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(OnCompleted);
}
public void Run()
{
if (!busy)
{
busy = true;
test = new Test(application, folderId, init);
worker.RunWorkerAsync();
}
}
private void DoWork(object sender, DoWorkEventArgs e)
{
test.Process();
test = null;
}
private void OnCompleted(object sender, RunWorkerCompletedEventArgs e)
{
busy = false;
init = false;
}
}
class Test
{
public const string key_preCreateProperty ="preCreate";
public const string key_postCreateProperty = "postCreate";
private Outlook.Application application;
private string folderId;
private bool createData;
public Test(Outlook.Application application,string folderId,bool createData)
{
this.application = application;
this.folderId = folderId;
this.createData = createData;
}
public void Process(){
Examine();
if(createData){
CreateData();
}
}
public void CreateData()
{
List<Poco> pocos = new List<Poco>();
for (int i = 0; i < 10; i++)
{
pocos.Add(
new Poco
{
Pre = "Pre" + i,
Post = "Post" + i
}
);
}
CreateContactItems(folderId,pocos);
}
public void Examine()
{
bool preIsLoaded = false;
bool postIsLoaded = false;
Debug.WriteLine(">>>Examine");
Outlook.MAPIFolder folder = application.Session.GetFolderFromID(folderId);
Outlook.Items folderItems = folder.Items;
int i = 0;
//print UserProperties registered to the items
foreach(Outlook.ContactItem contactItem in folderItems){
var itemUserProperties = contactItem.UserProperties;
string itemUserPropertiesString = "";
foreach (var itemProp in itemUserProperties)
{
Outlook.UserProperty prop = (Outlook.UserProperty)itemProp;
itemUserPropertiesString += " " +prop.Name + " " + prop.Value + " \n";
}
//HERE: sometimes it prints only Pre on the first index of the iteration
Debug.WriteLine(string.Format("i={0} , itemUserProperties Count={1} , following UserProperties: \n{2}", i++, itemUserProperties.Count, itemUserPropertiesString));
string pre = null;
string post = null;
try
{
pre = contactItem.GetUserProperty(key_preCreateProperty);
preIsLoaded = true;
}
catch(KeyNotFoundException ex){
Debug.WriteLine("Error: Pre Not found"); //should not happen - doesn't happen
}
try
{
post = contactItem.GetUserProperty(key_postCreateProperty);
postIsLoaded = true;
}
catch (KeyNotFoundException ex)
{
Debug.WriteLine("Error: Post Not found"); //shoul not happen - happens rarely totally indeterminitic
}
Marshal.ReleaseComObject(itemUserProperties);
}
Debug.WriteLine("<<<Examine");
if (folderItems.Count > 0 && (!preIsLoaded || !postIsLoaded))
{
MessageBox.Show("preIsLoaded="+preIsLoaded +" \n" +"postIsLoaded="+postIsLoaded);
}
Marshal.ReleaseComObject(folderItems);
Marshal.ReleaseComObject(folder);
}
public void CreateContactItems(string folderId,List<Poco> pocos)
{
Outlook.MAPIFolder folder = application.Session.GetFolderFromID(folderId);
foreach(Poco poco in pocos){
CreateContactItem(folder,poco);
}
Marshal.ReleaseComObject(folder);
}
public void CreateContactItem(Outlook.MAPIFolder testFolder,Poco data)
{
Outlook.ContactItem contactItem = application.CreateItem(Outlook.OlItemType.olContactItem);
contactItem.SetUserProperty(key_preCreateProperty, data.Pre);
contactItem.Save();
Outlook.ContactItem movedContactItem = (Outlook.ContactItem)contactItem.Move(testFolder);
Marshal.ReleaseComObject(contactItem);
contactItem = movedContactItem;
contactItem.FirstName = data.Pre;
contactItem.LastName = data.Post;
contactItem.SetUserProperty(key_postCreateProperty, data.Post);
contactItem.Save();
Marshal.ReleaseComObject(contactItem);
}
}
public static class Util
{
public static void SetUserProperty(this Outlook.ContactItem item, string name, dynamic value)
{
Outlook.UserProperty property = item.UserProperties[name];
if (property == null)
{
property = item.UserProperties.Add(name, Outlook.OlUserPropertyType.olText);
}
property.Value = value;
}
public static dynamic GetUserProperty(this Outlook.ContactItem item, string name)
{
Outlook.UserProperty property = item.UserProperties[name];
if (property != null)
{
return property.Value;
}
throw new KeyNotFoundException(string.Format("UserProperty name={0} not found", name));
}
}
public class Poco
{
public string Pre
{
get;
set;
}
public string Post
{
get;
set;
}
}
}
Thank you for any replies

Outlook Object Model cannot be used on a secondary thread within a COM addin. Outlook 2016 will raise an exception as soon as it detects an OOM object being accessed on a secondary thread.

Can't invoke DLL function without debug point

I have created a DLL in C# which creates message queue and object and send that object
to message queue. I added the reference of the created DLL to another application. Application
runs successfully when debug point is applied to DLL invoking function. But without debug point, it doesn't send object to message queue.
DLL Function as follows :
public void Enqueue()
{
try
{
this.CreateQueue(); //function that creates queue
Message msg = new Message();
DataTable dtOrd;
if (IsSingleOrder)
{
dtOrd = objDBTrans.funcGetNewOrdSingleDetails(this.DefaultSecurityCode, this.OrderCode, this.CreatedDate);
}
else
{
dtOrd = objDBTrans.funcGetBasketOrdDetails(this.DefaultSecurityCode, this.CreatedDate);
}
for (int iRows = 0; iRows < dtOrd.Rows.Count; iRows++)
{
DataRow drOrd;
drOrd = dtOrd.Rows[iRows];
objEMSOrdMap.funcAssignMapping(drOrd);
msg.Body = objEms;
msg.Label = strFileNamq + "_" + objEms.ClOrdID + " " + DateTime.Now.ToString();
queue.Send(msg);
}
}
catch (Exception ex)
{
}
}
DLL function that creates queue :
public void CreateQueue()
{
try
{
MessageQueue queue;
queue = new MessageQueue(msgQueue, false); //msgQueue = String containing queue name
}
catch (Exception)
{
}
}
Application function that invoke DLL function :
using EMSMsmqDll;
class EMSMSMQDemo : clsDBConnection
{
public void funcDemo()
{
MSMQService objSer = new MSMQService(); //Class from EMSMsmqDll that creates message queue and object and send that object to message queue
objSer.Enqueue();
}
}

Programmatic Execution Excel Macro on Remote Machine from a website

I have a website where users generate an Excel report using a macro, when I try to run it in my local machine it generates perfectly and runs the macro inside Excel. When I publish it into the server and at the same time I am logged in there (RDP open session) and try to run it from a browser outside that server it is also running as expected. The problem occurs when I am logged off in the server (RDP) then run it in a browser outside the server (ie from my machine) the macro does not run but creates my Excel.
This is the code that I am using
public class Report
{
protected Workbook Workbook { get; set; }
protected Application Excel { get; set; }
public void RunReport()
{
// Launch Excel on the server
Excel = new Application
{
DisplayAlerts = false,
ScreenUpdating = false,
Visible = false
};
// Load the workbook template
Workbook = Excel.Workbooks.Open(#"D:\Book1.xlt");
// Execute macros that generates the report, if any
ExecuteMacros();
Workbook.SaveAs(#"D:\Ray'sTesting.xls", XlFileFormat.xlExcel8);
QuitExcel();
}
private void QuitExcel()
{
if (Workbook != null)
{
Workbook.Close(false);
Marshal.ReleaseComObject(Workbook);
}
if (Excel != null)
{
Excel.Quit();
Marshal.ReleaseComObject(Excel);
}
}
private void ExecuteMacros()
{
const string legacyModuleName = "Module1";
const string legacyMacroName = "myMacro";
bool legacyMacroExists = false;
try
{
var legacyMacroModule = Workbook.VBProject.VBComponents.Item(legacyModuleName);
if (legacyMacroModule != null)
{
int legacyMacroStartLine = legacyMacroModule.CodeModule.ProcStartLine[legacyMacroName, Microsoft.Vbe.Interop.vbext_ProcKind.vbext_pk_Proc];
legacyMacroExists = legacyMacroStartLine > 0;
}
}
catch (Exception)
{
legacyMacroExists = false;
}
if (!legacyMacroExists)
{
return;
}
// VBA code for the dynamic macro that calls the CI2 legacy macro
var moduleCode = new StringBuilder();
moduleCode.AppendLine("Public Sub LaunchLegacyMacro()");
moduleCode.AppendLine(string.Format("{0}.{1}", legacyModuleName, legacyMacroName));
moduleCode.AppendLine("End Sub");
// Add the dynamic macro to the ThisWorkbook module
var workbookMainModule = Workbook.VBProject.VBComponents.Item("ThisWorkbook");
workbookMainModule.CodeModule.AddFromString(moduleCode.ToString());
// Execute the dynamic macro
Microsoft.VisualBasic.Interaction.CallByName(Workbook, "LaunchLegacyMacro", Microsoft.VisualBasic.CallType.Method, new object[] { });
}
}

I got this working by editing the registry every time we run the excel macro by
private static void ModifyExcelSecuritySettings()
{
// Make sure we have programmatic access to the project to run macros
using (var key = Microsoft.Win32.Registry.CurrentUser.OpenSubKey(#"Software\Microsoft\Office\14.0\Excel\Security", true))
{
if (key != null)
{
if ((int)key.GetValue("AccessVBOM", 0) != 1)
{
key.SetValue("AccessVBOM", 1);
}
key.Close();
}
}
}
So the code should look like this
public void RunReport()
{
ModifyExcelSecuritySettings();
// Launch Excel on the server
Excel = new Application
{
DisplayAlerts = false,
ScreenUpdating = false,
Visible = false
};
.....
I also created a blog post for the full solution which you can view here
http://anyrest.wordpress.com/2012/06/22/programmatic-execution-excel-macro-on-remote-machine-from-a-website/