I created a web service using ASP.net / C#. I added a service reference to the .asmx file in my Windows Phone 7 project (C# again). Under normal circumstances this works great.
I need to be able to handle situations when the web service is down or otherwise throws an error. When the service is unavailable, I get an error in a Reference.cs file (this appears to be something autogenerated when I added the Service Reference) when it tries to get the _result value. The inner exception of this is
"The remote server returned an error: NotFound.".
After getting the error, the app stops executing. I need to be able to catch this error so the app doesn't stop.
This is the code I call to execute my web service.
HighScoresWSSoapClient client = new HighScoresWSSoapClient();
client.LoadUserByANIDCompleted += this.client_LoadUserByANIDCompleted;
client.LoadUserByANIDAsync(this.anid);
I added a try/catch block in the client_LoadUserByANIDCompleted event.
In the debugger, when I it the error, execution of the app stops. If I press play, it then proceeds to enter the try/catch block and it does correctly go to the catch section where I can handle it...
But because it stops initially on the _result line, it doesn't normally get to that point. I'm at a loss why it won't bubble up to my try/catch without pressing play again and not sure how to make this work in a real world situation.
I hope this is enough info to go on and makes sense. Thanks for the help!
The first thing you should do is enable WCF logging and use the Service Trace Viewer to view its output. See this previous answer for more info.
It appears this is just a strange thing the debugger does and there isn't a way around it. If you run this code outside of the debugger, it bubbles the error up to the try/catch block and you can handle it. Inside the debugger, you must press play to go through it but then you can handle it too.
Related
I made a Window service and let it work automatically and under localsystem account, when the service starts it fires this message for me and then stops
The [service name] service on local computer started and then stopped. Some Services stop automatically if they are not in use by another services or programs.
What's the problem and what's the solution?
Either you are not starting any threads on the OnStart method to do work, or there is an exception raised within your OnStart method.
If an exception is thrown, it will appear in the Windows Event log. The Windows Event log is a good place to start in any case.
Generally an OnStart method looks like this:
Thread _thread;
protected override void OnStart(string[] args)
{
// Comment in to debug
// Debugger.Break()
// Do initial setup and initialization
Setup();
// Kick off a thread to do work
_thread = new Thread(new MyClass().MyMethod)
_thread.Start();
// Exit this method to indicate the service has started
}
This particular error message means what it says - that your service has started but then quite soon it exited for some reason. The good news is that your service is actually doing something, so you have the executable configured and running as a service properly.
Once started, for some reason it is quitting. You need to find out why this is. Add some debugging to tell you its up and running and known exit cases. If that doesn't reveal the problem then add some debugging to let you know it's still running and work backwards from when that stops.
Are you tracing out any debug information? Most likely an exception is being thrown during your initialization. I would trace out all your exceptions and use Debugview to view them.
I had a similar problem that occurred because my Event Logs were full and the service was unable to write to them. As such, it was impossible to debug by looking for messages in the Event Viewer. I put a try/catch and dumped the exception out to a file. I had to change the settings on my logs to fill as needed instead of every 7 days and this allowed the services to start.
Of course, the root of the problem for me is that I have a nVidia driver issue that is flooding my event logs and now I'm probably beating on the disk, but that's another issue.
Maybe you need to run the service as Local System Account. See this post by Srinivas Ganaparthi.
I had the same issue starting JBoss, then I changed the JAVA_HOME variable, it worked for me. It was the JBoss version that doesn't support the 1.6, it supports 1.5.
I had similar problem and it turned out in my case that the program simply crashed in OnStart method. It tried to read some file that it couldn't find but I suppose that any other program crash would give the same result. In case of Windows forms application you would get some error message but here it was just "your service started and stopped"
If you ever need, like me to read some files from the directory where Windows Service .exe is located, check this topic:
Getting full path for Windows Service
In my case, a method in my service, was being called recursively (as no terminate condition being true) and after specific time my service was being stopped.
I created a windows service which watches a directory. When a file is dumped into it, it takes the data and puts it into a database. Then this file is moved to another directory and deleted. It works fine in debug mode. But when i install it on my computer it stops after throwing the data into the database and the file in question is neither moved or deleted. I suspect a permission issue is involved. I tried to create a event log:
public Service1()
{
InitializeComponent();
if (!System.Diagnostics.EventLog.SourceExists("MySource"))
{
System.Diagnostics.EventLog.CreateEventSource(
"MySource", "MyNewLog");
}
eventLog1.Source = "MySource";
eventLog1.Log = "MyNewLog";
}
So i have three questions.
(1) What could be causing my service to work as described in debug but fail when installed on my computer.(2) I have initiated a event log as shown above. But do i need to add other code to record the event of my service stopping. I presume this would be done in a 'override onShutdown' method.(3) Finally when my service stops, i want to look at the event log. But i do not know how to do this, is in administrative tools? stored as a file on some directory?
Here is edit to this post in lieu of the grateful advice given below.
try
{
File.Move(e.FullPath, finalString);
File.Delete(e.FullPath);
}
catch(Exception q)
{
EventLog.WriteEntry("MySource", q.ToString(), EventLogEntryType.Error);
using (StreamWriter w = new StreamWriter(ConfigurationManager.AppSettings["fmd"], true))
{
w.Write(DateTime.Now.ToString("dd-MM-yyyy_hh-mm-ss"));
w.Write(q.ToString());
}
}
As per suggestion i put a try-catch around the file move and delete plus i added a OnShutdown method:
protected override void OnShutdown()
{
using (StreamWriter w = new StreamWriter(ConfigurationManager.AppSettings["ond"], true))
{
w.Write("stop OnShutdown");
}
//EventLog.WriteEntry("MySource", message, EventLogEntryType.Error);
}
I do not know how to pass any system error message to the shutdown method, so any advice appreciated. When i installed my modified code as a service, it again stopped before moving or deleting the files. Neither of my two logs accessed by a stream recorded anything. Plus the event viewer showed nothing either?
You can write as following,
if (!EventLog.SourceExists("MySource"))
EventLog.CreateEventSource("MySource", "Application");
EventLog.WriteEntry("MySource", message, EventLogEntryType.Error);
to view the event log messages, Goto Administrator Tools -> Event Viewer and look for the source you have created. or Just simply type eventvwr in run window.
When Services installed, it works under SYSTEM User account where service might not have access to some resources. Please put logs and see where exactly the issue is.
If you service installed in your development machine, use attach to process option under DEBUG Menu in Visual Studio to find out.
What could be causing my service to work as described in debug but fail when installed on my computer?
Permissions. The service is likely running under LocalSystem or Network Service if you didn't provide a different identity.
I have initiated a event log as shown above. But do i need to add other code to record the event of my service stopping. I presume this would be done in a 'override onShutdown' method?
Yes, you're assumption is correct.
Finally when my service stops, i want to look at the event log. But i do not know how to do this, is in administrative tools?
Just hit Windows Key+R to get the Run dialog and type eventvwr.
Well i found the reason for all the commotion. I eventually found some logs in the event viewer. They were listed in Administrative events in custom logs. There were three error logs: .Net runtime; Application error & Service Control Manager. In '.Net Runtime' the stack showed a unhandled exception for system.windows.forms. I stupidly included a pop up box in my release version. But even when i commented this away; i got a error. So i went back and found other message boxes, primarily in try catch statements. Removed these and solved the issue.
I have a console application written in C#. This application runs as automation to test a web service.
Flow:
Log in to network share (impersonate user)
copy mp3 file to local disc
convert mp3 to wav
downsample
trim wave
extract some useful data from wav
send http request
delete local files
write out some stuff to tsv
The application will run great for several hours (usually takes about 24 hours to complete the test). but every once and a while I will get this message: "The application has stopped working. I have been running this is VS 2012 in debug mode so, I can see what line throws any error. problem is, that I have not been able to catch the line (or method) that is throwing the error. I originally thought that the Domain controller was causing this issue due to power settings.
How can I capture exactly what error is bubbling its way up the stack?
Does all that run in a loop of some kind? Or on a timer?
Perhaps put a try-catch around the body of the loop or the method that runs all your code, add a logging framework of your choice (log4net or nlog seem good) and then in the catch log the exception. Most logging frameworks allow you to include the exception and will include stacktrace, etc.
Putting debug logging throughout the process can also help to narrow down where it's happening.
You can go to the Event Viewer on the operating system the console application is running on and then click on "Application". Event viewer logs and displays all exceptions thrown on any application running on the operating system.
try
{
// your code
}
catch (Exception e)
{
System.IO.File.WriteAllText(#"Z:\err.txt", e.ToString());
}
Note that access to windows drives are denied for non administrators so replace Z: with your choice.
I recommend you using a logging framework.
I use log4net in almost all applications. Its very simple to use and configure.
private static readonly log4net.ILog log = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
try
{
// do whatever
}
catch(Exception ex)
{
// Log an error with an exception
log.Error("Exception thrown", ex);
}
By using these kind of libraries you can get your log data output to file, database or even written to the windows event-viewer for instance.
It looks like the exception code you are getting happens when you try to use something that is already been garbage collected. Are you using anything after it is disposed?
Knowledge Base Article for 0xc0000005
I need my service to check for existence and structure of certain files during its startup and exit/fail/stop if some conditions aren't met.
I read this thread: What is the proper way for a Windows service to fail?
but it does not help.
I set the ServiceBase.ExitCode property non-zero and then call ServiceBase.Stop. But I get 5 event log entries. See below:
Starting service. (I log this event via code)
Config.xml file not found. (I log this ERROR event via code)
Service stopped successfully. (SCM logs this message)
Service started successfully. (SCM logs this message)
Service cannot be started. The handle is invalid (SCM logs this message)
As you see everything goes OK except for the last two entries. Why are they there? What can I do to properly shutdown the service during startup? Why doesn't SCM see the service as stopped/failed?
You don't provide enough code to really know, but I suspect you are trying to validate the service and stop it in either the constructor or the OnStart. The way I like to handle services is start my timer in the OnStart. In the first interval of the timer I can validate all the code, if its invalid close the Service. If its valid, reset the interval of the timer to how frequently I want it to run then set a bool that tells it not to check for validity of files again.
What is the return code you are using for your ExitCode? If it matches the corresponding windows ExitCode, then that is what will be recorded by SCM. I'm assuming you are returning a 6 for your ExitCode.
The other thing is if you can run on Default values do that, let Config.xml be missing and just record the problem in the EventLog. "Configuration file Missing"
If you really want it to just abort during OnStart, set your ExitCode and then Throw an Exception (InvalidArgumentException, InvalidOperationException) for example
This article also has some good advice. .NET: Which Exception to Throw When a Required Configuration Setting is Missing?
You are trying to start second instance of service (another service registered for the same .exe)
I have a simple web service that looks something like this:
[WebMethod]
public OrderForecastItem GetOrderForecast(int shipTo, string catalogName, bool showPricing)
{
return OrderForecastManager.GetOrderForecast(shipTo, catalogName, showPricing);
}
I'm calling it from another place in a fairly simple way:
using (OrderForecastWS.OrderForecastWS service = new OurSite.Web.Reporting.OrderForecastWS.OrderForecastWS())
{
OrderForecastItem orderForecastItems = service.GetOrderForecast(2585432, "DENTAL", false);
}
After some gymnastics to get the systems to understand that I'm talking about the same type of objects on the client and server sides (I had to open the Reference.cs file inside my Web References, delete the generated OrderForecastItem and add a link to our real OrderForecastItem), the system runs and attempts to get the item.
Unfortunately, it now bombs during the service call, claiming:
Exception There is an error in XML document (1, 1113).(InvalidOperationException)
I can go to the web service in a browser, put in the same values, and I get a seemingly valid XML response. (It looks okay to me, and I ran it through the XML parser at W3Schools, and it cleared it.)
I think the numbers in the error are supposed to be the line and character number...but the browser seems to reformat the xml document, so I can't easily see what the original (1, 1113) location is.
I don't see an easy way to intercept the response and examine it, since it seems to be blowing up as soon as it gets it.
How can I debug this?
If you control the service, you can step into it. If it is a part of your solution and hosted in VS WebDev on your local box, just F11 from Visual Studio, if service is hosted remotely (eg by IIS on other computer) run remote debugging tool on service host msdn, and then you will be able to step in to the service remotely.
By the way, you can tell Visual Studio to re-use objects from referenced libraries for types from the service: just pick configure Service Reference from service context menu and tell which libraries to re-use.
On second thought this error may happen if returned XML could not be deserialized into your business object. May happen when class is changed on either side, or you are trying to use different version of business library than service is using.
If you use Firefox, I'd recommend Firebug. You'll be able to easily view the response from the website in its original format, which might get you closer to the line and position you're looking for.