How to prevent WMI quotas from overflowing? - c#

I am using a C# application to monitor the processes launched from a particular folder, and I am using WMI for monitoring. My WMI query is like
SELECT * FROM __InstanceCreationEvent WITHIN 5 WHERE TargetInstance ISA 'Win32_Process' AND TargetInstance.ExecutablePath LIKE '{0}%'
where I substitute the parameter with the path to the folder which I am intereseted. The WMI query is working fine and I am subscribing to the event notifications to do some additional processsing when a process from the particular folder comes up. The monitoring tool runs fine for hours after which I start getting a WMI QuotaViolation exception in my app. Once this happens I need to restart the Windows Management Instrumentation service to get the thing working.
I was initially using a
`SELECT * FROM __InstanceCreationEvent WITHIN 5 WHERE TargetInstance ISA 'Win32_Process'`
query and then checking the processes folder in the event notification, the modification in the query was done hoping it would reduce the result set and therefore prevent the Quota Violation.
Is there any way to flush the WMI quotas periodically or any other method whereby I can prevent the QuotaViolation? What is the best way to handle a QuotaViolation scenario?
Edit:
This is my process watcher object :
public class ProcessWatcher : ManagementEventWatcher
{
private string folder = "";
// Process Events
public event ProcessEventHandler ProcessCreated; //notifies process creation
//add any more event notifications required here
// WMI WQL process query strings
static readonly string WMI_OPER_EVENT_QUERY = #"SELECT * FROM __InstanceCreationEvent WITHIN 5 WHERE TargetInstance ISA 'Win32_Process'";
static readonly string WMI_OPER_EVENT_QUERY_WITH_PROC =
WMI_OPER_EVENT_QUERY + " and TargetInstance.Name = '{0}'";
public ProcessWatcher(string basepath)
{
folder = basepath;
Init(string.Empty);
}
public ProcessWatcher(string processName, string basepath)
{
folder = basepath;
Init(processName);
}
private void Init(string processName)
{
this.Query.QueryLanguage = "WQL";
if (string.IsNullOrEmpty(processName))
{
this.Query.QueryString = string.Format(WMI_OPER_EVENT_QUERY + #" AND TargetInstance.ExecutablePath LIKE '{0}%'", folder.Replace(#"\",#"\\")) ;
}
else
{
this.Query.QueryString =
string.Format(WMI_OPER_EVENT_QUERY_WITH_PROC, processName);
}
this.EventArrived += new EventArrivedEventHandler(watcher_EventArrived);
}
private void watcher_EventArrived(object sender, EventArrivedEventArgs e)
{
try
{
ManagementBaseObject mObj = e.NewEvent["TargetInstance"] as ManagementBaseObject;
if (mObj != null)
{
Win32_Process proc = new Win32_Process(mObj);
if (proc != null)
{
folder = folder.ToLower() ?? "";
string exepath = (string.IsNullOrEmpty(proc.ExecutablePath)) ? "" : proc.ExecutablePath.ToLower();
if (!string.IsNullOrEmpty(folder) && !string.IsNullOrEmpty(exepath) && exepath.Contains(folder))
{
if (ProcessCreated != null) ProcessCreated(proc);
}
}
proc.Dispose();
}
mObj.Dispose();
}
catch(Exception ex) { throw; }
finally
{
e.NewEvent.Dispose();
}
}
I create a ProcessWatcher object at app startup, in a viewmodel constructor like :
watch = new ProcessWatcher(BasePath);
watch.ProcessCreated += new ProcessEventHandler(procWatcher_ProcessCreated);
watch.Start();
The start call is where the QuotaViolation is raised if I try to start it a second time without restarting WMI.
At app exit, I am disposing off the ProcessWatcher object like :
watch.Stop();
watch.Dispose();
The Relevant Stack trace is :
Exception InnerException [System.Management.ManagementException: Quota violation
at System.Management.ManagementException.ThrowWithExtendedInfo(ManagementStatus errorCode)
at System.Management.ManagementEventWatcher.Start()
at App.ProcessTabViewModel1..ctor()

System.Management.ManagementException: Quota violation
Yes, that happens. I wrote a little test program, based on your snippet after adding the missing pieces:
static void Main(string[] args) {
for (int ix = 0; ix < 1000; ++ix) {
var obj = new ProcessWatcher("");
obj.ProcessCreated += obj_ProcessCreated;
obj.Start();
}
}
Kaboom! With the exact same stack trace as you quoted. It conked out at ix == 76. In other words, the WMI quota for this query is 75. Tested in Windows 8.1. Feels about right, this is a very expensive query, none too fast either.
You are going to have to do this fundamentally different, create only one query. One is enough, you probably got into trouble by doing this for many folders. Attack that differently, do your own filtering when you get the event. A rough example (I didn't quite get the filtering you want to do):
public class ProcessWatcher2 : IDisposable {
public delegate void ProcessCreateEvent(string name, string path);
public event ProcessCreateEvent ProcessCreated;
public ProcessWatcher2(string folder) {
this.folder = folder;
lock (locker) {
listeners.Add(this);
if (watcher == null) Initialize();
}
}
public void Dispose() {
lock (locker) {
listeners.Remove(this);
if (listeners.Count == 0) {
watcher.Stop();
watcher.Dispose();
watcher = null;
}
}
}
private static void Initialize() {
var query = new WqlEventQuery(#"SELECT * FROM __InstanceCreationEvent WITHIN 5 WHERE TargetInstance ISA 'Win32_Process'");
watcher = new ManagementEventWatcher(query);
watcher.EventArrived += watcher_EventArrived;
watcher.Start();
}
private static void watcher_EventArrived(object sender, EventArrivedEventArgs e) {
using (var proc = (ManagementBaseObject)e.NewEvent["TargetInstance"]) {
string name = (string)proc.Properties["Name"].Value;
string path = (string)proc.Properties["ExecutablePath"].Value;
lock (locker) {
foreach (var listener in listeners) {
bool filtered = false;
// Todo: implement your filtering
//...
var handler = listener.ProcessCreated;
if (!filtered && handler != null) {
handler(name, path);
}
}
}
}
}
private static ManagementEventWatcher watcher;
private static List<ProcessWatcher2> listeners = new List<ProcessWatcher2>();
private static object locker = new object();
private string folder;
}

Related

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.

Keeping console app alive and event-driven while processes run in the background

I am trying to write a console application that acts as a "job manager" by running processes in the background. These processes would be running JScript files with arguments passed in. This console application will be distributed across many machines, and will pull from a centralized source (ie. database) to get jobs. The purpose of this application is to eliminate the need for individualized batch files on all of these machines.
I am having trouble keeping the application alive. In the code that I included, you can see in my main function that I am making an initial call to the JobManger's StartNewJobs() method. After this initial call to this method, I'd like my application to then be event-driven, only waking up and running when a process has exited, allowing me to start a new process. The problem I am running into is that once the main() function finishes (when the initial StartNewJobs() method finishes) the console closes and the program ends.
My question is what is the proper way to keep my console application alive and allow it to be event-driven rather than procedural? I know I can probably throw in a while(true) at the end of the main function, but that seems sloppy and incorrect.
Batch file we are trying to replace:
C:\Windows\SysWOW64\cscript.exe c:\temp\somejscriptfile.js 49f1bdd8-5e6b-40cc-92bc-eb20c237a959
C:\Windows\SysWOW64\cscript.exe c:\temp\somejscriptfile.js 654e3783-a1b6-43be-8027-c7d060bf131f
...
Program.cs:
using DistributedJobs.Data;
using DistributedJobs.Logging;
using DistributedJobs.Models;
using Microsoft.Practices.EnterpriseLibrary.Common.Configuration;
using Microsoft.Practices.EnterpriseLibrary.ExceptionHandling;
using System;
namespace DistributedJobs
{
class Program
{
static void Main(string[] args)
{
//Get intial objects/settings
ILogger logger = new Logger(Properties.Settings.Default.LoggingLevel, EnterpriseLibraryContainer.Current.GetInstance<ExceptionManager>());
IDataProvider dataProvider = new SQLDataProvider();
DMSPollingJobType availableJobTypes = DMSPollingJobType.FlatFile;
if (Properties.Settings.Default.SupportsVPN)
{
availableJobTypes |= DMSPollingJobType.VPN;
}
String executableLocation = Properties.Settings.Default.ExecutableLocation;
String jsLocation = Properties.Settings.Default.JSLocation;
Int32 maxProcesses = Properties.Settings.Default.MaxProcesses;
//Create job manager and start new processes/jobs
DMSJobManager jobManager = new DMSJobManager(logger, dataProvider, availableJobTypes, executableLocation, jsLocation, maxProcesses);
jobManager.StartNewJobs();
}
}
}
JobManager.cs:
using DistributedJobs.Models;
using System.Diagnostics;
using System;
using System.Collections.Generic;
using DistributedJobs.Logging;
namespace DistributedJobs.Data
{
public class JobManager
{
private IDataProvider DataProvider;
private ILogger Logger;
private Dictionary<Job, Process> RunningProcesses;
private JobType AvailableJobTypes;
private String ExecutableLocation;
private String JSLocation;
private Int32 MaxProcesses;
public Boolean CanStartNewJob
{
get
{
Boolean canStartNewJob = false;
if (RunningProcesses.Count < MaxProcesses)
{
canStartNewJob = true;
}
foreach (KeyValuePair<Job, Process> entry in RunningProcesses)
{
if (entry.Key.JobType != JobType.FlatFile)
{
canStartNewJob = false;
break;
}
}
return canStartNewJob;
}
}
public JobManager(ILogger logger, IDataProvider dataProvider, JobType availableJobTypes, String executableLocation, String jsLocation, Int32 maxProcesses)
{
Logger = logger;
DataProvider = dataProvider;
RunningProcesses = new Dictionary<Job, Process>();
AvailableJobTypes = availableJobTypes;
ExecutableLocation = executableLocation;
JSLocation = jsLocation;
MaxProcesses = maxProcesses;
}
public void StartNewJobs()
{
while (CanStartNewJob)
{
Job newJob = DataProvider.GetNextScheduledJob(AvailableJobTypes);
if (newJob != null)
{
Process newProcess = CreateNewProcess(newJob);
RunningProcesses.Add(newJob, newProcess);
newProcess.Start();
}
}
}
public Process CreateNewProcess(Job job)
{
ProcessStartInfo startInfo = new ProcessStartInfo();
startInfo.FileName = ExecutableLocation;
startInfo.Arguments = JSLocation + " " + job.JobID.ToString();
startInfo.UseShellExecute = false;
Process retProcess = new Process()
{
StartInfo = startInfo,
EnableRaisingEvents = true
};
retProcess.Exited += new EventHandler(JobFinished);
return retProcess;
}
public void JobFinished(object sender, EventArgs e)
{
Job finishedJob = null;
foreach (KeyValuePair<Job, Process> entry in RunningProcesses)
{
if ((Process)sender == entry.Value)
{
finishedJob = entry.Key;
break;
}
}
if (finishedJob != null)
{
RunningProcesses.Remove(finishedJob);
StartNewJobs();
}
}
}
}
You could try using Application.Run()(System.Windows.Forms). This will start a standard message loop.
So at the end of your Main method just add a Application.Run():
static void Main(string[] args)
{
//Get intial objects/settings
ILogger logger = new Logger(Properties.Settings.Default.LoggingLevel, EnterpriseLibraryContainer.Current.GetInstance<ExceptionManager>());
IDataProvider dataProvider = new SQLDataProvider();
DMSPollingJobType availableJobTypes = DMSPollingJobType.FlatFile;
if (Properties.Settings.Default.SupportsVPN)
{
availableJobTypes |= DMSPollingJobType.VPN;
}
String executableLocation = Properties.Settings.Default.ExecutableLocation;
String jsLocation = Properties.Settings.Default.JSLocation;
Int32 maxProcesses = Properties.Settings.Default.MaxProcesses;
//Create job manager and start new processes/jobs
DMSJobManager jobManager = new DMSJobManager(logger, dataProvider, availableJobTypes, executableLocation, jsLocation, maxProcesses);
jobManager.StartNewJobs();
// start message loop
Application.Run();
}

EWS streaming notifications not received

Afternoon all,
I have a windows service which subscribes to an Office365 email account and awaits new emails, when they arrive it processes their attachments, and all is well with the world.
But... for some reason, the applications stops receiving notifications after an undetermined amount of time.
I have handled the 'OnDisconnect' event and reestablish a connection as shown in the below code, but that doesnt seem to be fixing this issue. The windows service continues to run fine, and if I restart the service everything is good again, until is failed again.
This is the my class for running exchange:
public class ExchangeConnection
{
static readonly ExchangeService Service = Exchange.Service.ConnectToService(UserDataFromConsole.GetUserData(), new TraceListener());
public event EmailReceivedHandler OnEmailReceived;
public ExchangeConnection()
{
}
public void Open()
{
SetStreamingNotifications(Service);
var signal = new AutoResetEvent(false);
signal.WaitOne();
}
private void SetStreamingNotifications(ExchangeService service)
{
var streamingsubscription = service.SubscribeToStreamingNotifications(new FolderId[] { WellKnownFolderName.Inbox }, EventType.NewMail);
var connection = new StreamingSubscriptionConnection(service, 30);
connection.AddSubscription(streamingsubscription);
connection.OnNotificationEvent += OnEvent;
connection.OnSubscriptionError += OnError;
connection.OnDisconnect += OnDisconnect;
connection.Open();
}
public void MoveEmail(ItemId id, String folderName = "Archived Emails")
{
var rootFolder = Folder.Bind(Service, WellKnownFolderName.Inbox);
var archivedFolder = rootFolder.FindFolders(new FolderView(100)).FirstOrDefault(x => x.DisplayName == folderName);
if (archivedFolder == null)
{
archivedFolder = new Folder(Service) { DisplayName = folderName };
archivedFolder.Save(WellKnownFolderName.Inbox);
}
Service.MoveItems(new List<ItemId> {id}, archivedFolder.Id);
}
#region events
private void OnDisconnect(object sender, SubscriptionErrorEventArgs args)
{
//The connection is disconnected every 30minutes, and we are unable to override this,
//so when we get disconnected we just need to reconnect again.
var connection = (StreamingSubscriptionConnection)sender;
connection.Open();
}
private void OnEvent(object sender, NotificationEventArgs args)
{
var subscription = args.Subscription;
// Loop through all item-related events.
foreach (var notification in args.Events)
{
switch (notification.EventType)
{
case EventType.NewMail:
if (notification is ItemEvent)
{
var email = Item.Bind(Service, new ItemId(((ItemEvent) notification).ItemId.UniqueId));
OnEmailReceived(new EmailReceivedArgs((EmailMessage)email));
}
break;
}
}
}
private void OnError(object sender, SubscriptionErrorEventArgs args)
{
var e = args.Exception;
Logger.LogException(e,LogEventType.Error);
}
#endregion events
}
Any help would be great, thanks.
EDIT:
After improving the error logging I have found this exception occuring:
Exception: The specified subscription was not found.
Any ideas what is causing this?
With Office365 you need to make sure you deal with affinity see http://msdn.microsoft.com/en-us/library/office/dn458789(v=exchg.150).aspx . Adding those headers will ensure your requests will always routed to the correct servers.
Cheers
Glen

Thread run a "step" for each call C#

i have my main code executed from MainWindow.xaml.cs and a thread, called testThread.
I need testThread to read inside a folder (with subfolders too) decided by MainWindow and read one file per time, everytime MainWindow needs it. I know that using a thread is pretty useless with this example but i need this mechanic to be implemented in a bigger context.
What can be the best approach to realize this? My tought was to use a semaphore and lock the thread after every file read so i can unlock it everytime i need next file. Here what i tried to implement (and doesn't work):
MainWindow.cs
public static string myRootDir;
private void Button_test_Click(object sender, RoutedEventArgs e)
{
try
{
myRootDir = #"C:\";
testThread myThread = new testThread();
Thread workerThread = new Thread(myThread.start);
workerThread.Start();
//for this test i'm getting the first 10 files
for (int c1 = 1; c1 < 10; c1++ )
{
result.Text += myThread.getNext();
//this is just a test, so i wait 1 second from each request
Thread.Sleep(1000);
}
}
catch (Exception error)
{
result.Text = error.Message;
}
}
testThread.cs
public class testThread
{
private string rootDir = "";
public static string currentFilePath = "";
Semaphore mySemaphore = new Semaphore(0, 2);
public void start()
{
rootDir = MainWindow.myRootDir;
startReading(rootDir);
}
public string getNext()
{
mySemaphore.Release();
return currentFilePath;
}
private void startReading(string root)
{
//read all the files in current dir
foreach (string singleFilePath in Directory.GetFiles(root, "*.*"))
{
currentFilePath = singleFilePath;
mySemaphore.WaitOne();
}
//repeat for all subfolders
foreach (string singleDirPath in Directory.GetDirectories(root))
{
startReading(singleDirPath);
}
}
}
From debug i can see the code doesn't stop on mySemaphore.WaitOne();, and i suspect i'm doing other errors too!

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