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When is a Kofax Workflow Agent run?

When are workflow agents actually called?
I've installed my own workflow agent (this one) and write to a log on the second line in ProcessWorkflow (the first one being the log4net XmlConfigurator.Configure call with a newly created FileInfo instance.
The log is always written after the KTM Server module. This WOULD make sense, because I read a configuration which prompts the WFA to do something with the workflow data. But after the KTM Validation module (where the WFA is also configured to do something) the log is not written.
Is there an explanation, why I don't see any log entries? I've checked the kofax logs too, but I found no evidence there.
The exact code snippet looks like this:
public void ProcessWorkflow(ref IACWorkflowData workflowData)
{
XmlConfigurator.Configure(new FileInfo(#"C:\Program Files (x86)\Kofax\CaptureSS\ServLib\Configuration Files\log4net.config"));
log.Info("Workflow Agent started ...");
// rest of the code

So, since I kind of figured out how to use Workflow Agents, I decided to answer this question for future reference.
A Workflow Agent is being run every time a module has been executed. IIRC this includes viewing the properties with Batch Manager. The Workflow Agent will be called on the site where the module has been executed. So if you execute your automatic modules (i.e. PDF Generator, Export) on a server and Scan and Validation on client sites, the Workflow Agent will be executed on the server or the client station which executed the module respectively.
I actually forgot what didn't work in my original question, but I also ran into problems because I didn't register the DLL using RegAsm.exe. See my other Kofax-related question for more information about this: How to correctly install Workflow Agents in Kofax?

You can also use this in your code so that it only runs the logic when you want it to:
if (workflowData.CurrentModule.Name != "Scan" || workflowData.get_NextState().Name != "Ready")
{
return;
}

What's the recommended process for building Windows Services in .NET

I'm quite new to development of Windows Services (my background is in Web Development) and I'm a bit confused by the development process for Windows Services.
As I understand it, the service has to be installed every time you compile the code, and then run from the Services MMC snapin.
This seems like an awfully painful process to go through every time you make a change to your code.
Can someone shed some light on the 'recommended' approach for building services?
Thanks

To debug services, I generally use the following boilerplate for Main:
static void Main()
{
ServiceBase[] servicesToRun = new ServiceBase[] { new MyService(); };
#if !DEBUG
//run the service normally using ServiceBase.Run
ServiceBase.Run(servicesToRun);
#else
//debug the process as a non-service by invoking OnStart and then sleeping
foreach (ServiceBase s in servicesToRun)
{
var serviceType = s.GetType();
var onStartMethod = serviceType.GetMethod("OnStart", System.Reflection.BindingFlags.Instance |
System.Reflection.BindingFlags.NonPublic);
onStartMethod.Invoke(s, new object[] { new string[0] });
}
Debug.WriteLine("done starting services");
while (true)
Thread.Sleep(200);
#endif
}
What this does is use reflection to get the OnStart protected method for each service, invoke it, then sit in a sleep loop to keep the process running.
This example is assuming MyService is the service class that inherits from ServiceBase, which overrides OnStart to spawn off thread(s) and do its thing.
Here I'm using the DEBUG compile-time constant as the controlling factor of whether to start normally or debug as a non-service. If DEBUG is defined it will run in-process as a non-service. Otherwise it does its normal thing calling ServiceBase.Run. Feel free to use a command-line argument or whatever works best for you.

You may need some tweaks or re-factoring most of the logic to console app for easier testing, debugging, as what comes out of the box is really painful.
Here are some resources :
http://candordeveloper.com/2012/12/27/debugging-a-windows-service-application-without-install/
Running Windows Service Application without installing it
the easiest of them might be putting
#if DEBUG
//your logic
#endif
in your logic, putting a breakpoint and hitting F5, this is what i do most of the time.
Would be interesting to know if there is even better ways :)

Answers from Bravo 11 and Ic. give some good tips and tricks. I will add some:
Be aware that running as as service has also some implications regarding login / security context:
running under SYSTEM, you cannot access network file shares normally (there is a way adding the machine account to the ACL however)
running under a (domain) user account needs "logon as service" privileges, which is IMHO the most common cause of service starting problems in enterprise environments (the GPO settings may be adjusted). In addition, you do not have access to the desktop, so if a popup will be displayed waiting for the user, the service hangs.
in the development phase, you can swap DLLs or even the EXE if the service is not currently running without uninstall / install
use Windows event log extensively.
These differences between services and "normal application" are important enough for me to let this run directly on a server as often as possible.
In my services, I use:
protected override void OnStart(string[] args)
{
// this is not just a simple message, this has to be called very early before any worker thread
// to prevent a race condition in the .NET code of registering the event source
EventLog.WriteEntry("XXXXService is starting", EventLogEntryType.Information, 1000);
....
And do not forget that OnStart() and OnStop()should not contain long running code. You normally start a worker thread in OnStart() which runs until some notification (set in OnStop) was triggered.

Process.Start won't work

I am trying to launch a process from a web page's back-end code/app pool. This process will launch an App that i built myself.
For some reason, the process only works / runs when i start it from VS2013... it never works when i launch it from IIS(7.5) itself.
I am on a Windows 7 machine (both IIS host, and App location), and I've setup my web site to only be accessible via internal network.
Here's the code, followed by the config / attempts to fix the issue:
protected void btn_DoIt_Click(object sender, EventArgs e)
{
string file_text = this.txt_Urls.Text;
if (!String.IsNullOrWhiteSpace(file_text))
File.WriteAllText(ConfigurationManager.AppSettings["filePath"], file_text);
ProcessStartInfo inf = new ProcessStartInfo();
SecureString ss = GetSecureString("SomePassword");
inf.FileName = #"........\bin\Release\SomeExecutable.exe";
inf.Arguments = ConfigurationManager.AppSettings["filePath"];
inf.UserName = "SomeUserName";
inf.Password = ss;
inf.UseShellExecute = false;
//launch desktop app, but don't close it in case we want to see the results!
try
{
Process.Start(inf);
}
catch(Exception ex)
{
this.txt_Urls.Text = ex.Message;
}
this.txt_Urls.Enabled = false;
this.btn_DoIt.Enabled = false;
this.txt_Urls.Text = "Entries received and process started. Check local machine for status update, or use refresh below.";
}
Here are the things I've tried to resolve the issue:
Made sure the executing assembly was built with AnyCPU instead of
x86
Ensured that the AppPool that runs the app, also runs under the same account (SomeUsername) as the ProcessStartInfo specified.
Ensured that the specific user account has full access to the executable's folder.
Ensured that IIS_USR has full access to the executable's folder.
Restarted both the app pool and IIS itself many times over implementing these fixes
I am now at a loss as to why this simply will not launch the app... when i first looked into the event log, i saw that the app would die immediately with code 1000:KERNELBASE.dll, which got me on the AnyCPU config instead of X86 fix... that fixed the event log entries but the app still doesn't start (nothing comes up in task manager), and i get no errors in the event log...
if someone could help me fix this problem i would really appreciate it. This would allow me to perform specific tasks on my main computer from any device on my network (phone, tablet, laptop, etc etc) without having to be in front of my main PC...
UPDATE
The comment to my OP, and ultimate answer from #Bradley Uffner actually nailed the problem on the head: My "app" is actually a desktop application with a UI, and in order to run that application, IIS would need to be able to get access to the desktop and the UI, just like if it were a person sitting down in front of the PC. This of course is not the case since IIS is running only as a service account and it makes sense that it shouldn't be launching UI programs in the background. Also see his answer for one way of getting around this.

Your best bet might be to try writing this as 2 parts. A web site that posts commands to a text file (or database, or some other persistent storage), and a desktop application that periodically polls that file (database, etc) for changes and executes those commands. You could write out the entire command line, including exe path command arguments, and switches.
This is the only way I can really think of to allow a service application like IIS to execute applications that require a desktop context with a logged in user.

You should assign a technical user with enough high priviliges to the running application pool. By default the application pool is running with ApplicationPoolIdentity identy which has a very low priviliges.

Keep C# application running

I'm building a Windows Service that uses FileSystemWatcher, and runs in the background.
I don't want to keep on uninstalling and installing the service every time I want to debug, so would like to do most of my development in a normal program before moving it into a service. But I'm quite new to this, and when I run it, it just runs through the block and exits.
What would be a good way to keep the program running?

http://einaregilsson.com/run-windows-service-as-a-console-program/
I've used this before to debug my service as a Console application based on whether its running in an interactive user environment.
public partial class DemoService : ServiceBase
{
static void Main(string[] args)
{
DemoService service = new DemoService();
if (Environment.UserInteractive)
{
service.OnStart(args);
Console.WriteLine("Press any key to stop program");
Console.Read();
service.OnStop();
}
else
{
ServiceBase.Run(service);
}
}

while (true)
{
// Execute your program's functionality here.
}

I wrote a 7 part series a while ago titled: Building a Windows Service. It covers all the intricacies of building services, making them friendly to debug, and self-installing.
The basic feature set I was looking for was as follows:
Building a service that can also be used from the console
Proper event logging of service startup/shutdown and other activities
Allowing multiple instances by using command-line arguments
Self installation of service and event log
Proper event logging of service exceptions and errors
Controlling of start-up, shutdown and restart options
Handling custom service commands, power, and session events
Customizing service security and access control
The final result was a Visual Studio project template that creates a working service, complete with all of the above, in a single step. It's been a great time saver for me.
see Building a Windows Service – Part 7: Finishing touches for a link to the project template and install instructions.

Here’s documentation from MSDN # http://msdn.microsoft.com/en-us/library/7a50syb3(v=vs.80).aspx?ppud=4 . I have tried it before and it works under .NET Framework 3.x. I could not find my descriptive notes on it, at the moment.
Use the pragma #If DEBUG for debugging purposes like console outputs. Another is using the Debug object.
If you have any trouble with this, say so. I may be able to find my notes or make a Windows Service app myself, just to see if the steps on MSDN still work.

How do you debug a Windows Service?

I read the MSDN article on the topic. To quote:
Because a service must be run from
within the context of the Services
Control Manager rather than from
within Visual Studio, debugging a
service is not as straightforward as
debugging other Visual Studio
application types. To debug a service,
you must start the service and then
attach a debugger to the process in
which it is running. You can then
debug your application using all of
the standard debugging functionality
of Visual Studio.
Now my problem is that my service fails to start in the first place. First it crashes, and says:
An unhandled exception
(System.Runtime.InteropServices.COMException)
occurred in MyServiceName.exe[3596])
and suggests me to debug it (the debugger instance instantly crashes when I choose one). Then it says
Could not start the MyServiceName
service on Local Computer. Error
1053: The service did not respond to
the start or control request in a
timely fashion
So, how can I investigate/debug the reason that my service won't start? The thing is I created a console application that does EXACTLY what the service does and it works fine. (I mean I just copied the OnStart() method's and the main loop's contents to main).
Any help would be appreciated.
The Service is written in C# with heavy use of interop. I am using VS2008

You could use a parameter to let your application decide whether to start as service or regular app (i.e. in this case show a Form or start the service):
static void Main(string[] args)
{
if ((1 == args.Length) && ("-runAsApp" == args[0]))
{
Application.Run(new application_form());
}
else
{
System.ServiceProcess.ServiceBase[] ServicesToRun;
ServicesToRun = new ServiceBase[] { new MyService() };
System.ServiceProcess.ServiceBase.Run(ServicesToRun);
}
}
Now if you pass the parameter "-runAsApp" you can debug the application normally - the SCM won't pass this parameter, so you can also use it as service w/o any code change (provided you derive from ServiceBase)
Edit:
The other difference with windows services is identity (this might be especially important with InterOp) - you want to make sure you are testing under the same identity in "app" mode as well as service mode.
To do so you can use impersonation (I can post a C# wrapper if it helps, but this can be easily googled) in app mode to use the same identity your windows service will be running under i.e. usually LocalService or NetworkService.
If another identity is required you can add settings to the app.config that allow you to decide whether to use credentials, and if so which user to impersonate - these settings would be active when running as app, but turned off for the windows service (since the service is already running under the desired identity):
<appSettings>
<add key="useCredentials" value="false"/>
<add key="user" value="Foo"/>
<add key="password" value="Bar"/>
</appSettings>

I usually just manually set a breakpoint, then point it to the currently open project in c#. The code to set a breakpoint is:
System.Diagnostics.Debugger.Break();
That should get you started, then you can just step through your code and see what's really happening.

I stole this from C. Lawrence Wenham, so I can't really take credit, but you can programmatically attach a debugger to a service, WITHOUT breaking execution at that point, with the following code:
System.Diagnostics.Debugger.Launch();
Put this in your service's OnStart() method, as the first line, and it will prompt you to choose an instance of VS to attach its debugger. From there, the system will stop at breakpoints you set, and on exceptions thrown out. I would put an #if DEBUG clause around the code so a Release build won't include it; or you can just strip it out after you find the problem.

You can use WinDbg/NTSD (another debugger from the "Debugging tools for windows" package) to start a debugger together with your service.
To do this open "gflags" (also available in the above mentioned package) to the "Image file" tab and set the path to debugger executable for your image file (service);
If your service is marked as interactive (only possible if it runs under the SYSTEM account) you can directly start WinDbg, just set the debugger to something like "PATH_TO_WINDBG\windbg.exe -g -G" (the -g / -G are needed so that the debugger doesn't break execution on application start or end - the default behaviour). Now when starting your service the windbg window should pop-up and will catch any unhandled exception.
If your service is not interactive you can start the NTSD debugger (a command line debugger) in remote mode and connect to it from WinDbg (that can even be running in another PC). To do this set the debugger in gflags to something like "PATH_TO_NTSD\ntsd -remote tcp:port=6666,server=localhost". Then connect to the remote debugger by starting windbg with something like "windbg -remote tcp:port=6666,server=localhost" and you should have complete control over the other debugging session.
As for finding the source of the exception itself a windbg tutorial is over the topic here but as a start try to execute the "!analyze -v" command after the exception was caught - with some luck this is all information you'll need..
Note: maybe this is overkill for your case but with this approach you can even debug services during system start-up (I had once a timing problem with a service had an issue only when starting the first time with the system)

One thing I do (which may be kind of a hack) is put a Thread.Sleep(10000) right at the beginning of my OnStart() method. This gives me a 10-second window to attach my debugger to the service before it does anything else.
Of course I remove the Thread.Sleep() statement when I'm done debugging.
One other thing you may do is the following:
public override void OnStart()
{
try
{
// all your OnStart() logic here
}
catch(Exception ex)
{
// Log ex.Message
if (!EventLog.SourceExists("MyApplication"))
EventLog.CreateEventSource("MyApplication", "Application");
EventLog.WriteEntry("MyApplication", "Failed to start: " + ex.Message);
throw;
}
}
When you log ex.Message, you may get a more detailed error message. Furthermore, you could just log ex.ToString() to get the whole stack trace, and if your .pdb files are in the same directory as your executable, it will even tell you what line the Exception occurred on.

Add lots of verbose logging in your OnStart. It's painful and old school, but it works.

Seems like the problem is with the user context. Let me confirm whether my assumptions are right.
When you say that the code works perfectly from console application, I assume you are executing the Console application under the same user which you had logged in.
When you say that the same code crashes while called from the windows service, I assume the service is running in "Local System" account in your development machine.
If both my assumptions are right, please try out the following steps.
In the services listing right-click your service, select properties and then "Log On" tab.
Select the option "This account" and provide the existing username and password.
Now try starting the service. It should now start without any errors.
Following could be the root cause of your error
If you are using SQL Server make sure you are not using SSPI authentication.
If you are trying to read any shared folder\resource which you don't have permission when using "local system" account.
If any of the required dependencies required by the application is in a different folder which the "Local System" user doesn't have permission to access.
If you are using VBA automation which wont work in "Local System" account.
Try disabling your firewall or antivirus.

You could add some logging around the interop calls to find out which one fails.
Also services by default aren't associated with a desktop; if you open the services.msc control panel applet, get the properties of your service, go to the "Log On" tab, you could check "Allow service to interact with desktop". This could fix the problem for you in some cases.

I would assume the reason could be causing because of heavy use of interops. So you need to tackle this problem differently. I would suggest create a windows or console app with same logic of you service and make sure that it works first without any issues, and then you may want to go with creation of the Win service.

Debugging services is a pain, particularly since startup seems to be when many of the problems manifest (at least for us).
What we typically do is extract as much of the logic as possible to a single class that has start and stop methods. Those class methods are all that the service calls directly. We then create a WinForm application that has two buttons: one to invoke start, another to invoke stop. We can then run this WinForm applicaiton directly from the debugger and see what is happening.
Not the most elegant solution, but it works for us.

Check out this question, which discusses how to catch unhandled exceptions in a window service.

In order to attach a debugger to the Windows Service, it needs to be started first. The reason why the service failed to start can be checked in Windows Event Log.
After that the process of attaching a debugger is pretty straight forward from Visual Studio Debug->Attach To Process.

What I've done is implemented by OnStart() to look something like this:
_myBusinessObject = new MyBusinessObject();
After the Business Object has been constructed, timers and IPC handlers do all the real (Service) work.
Doing it like this allows you to create a Forms/WPF application that call the same code above in the Form_Loaded handler. This way, debugging the Forms application is the exact same as debugging the Service.
The only issue is that if you are using app.config values, there will be a second app.config file that needs to be kept up-to-date.

Use following Code in Service OnStart Method:
System.Diagnostics.Debugger.Launch();
Choose Visual Studio option from Pop Up message

read the 2 articles mentioned here:
http://geekswithblogs.net/BlackRabbitCoder/archive/2011/03/01/c-toolbox-debug-able-self-installable-windows-service-template-redux.aspx

Step 1 - Add #if region to your Program.cs
static class Program
{
/// <summary>
/// The main entry point for the application.
/// </summary>
static void Main()
{
ServiceBase[] ServicesToRun;
ServicesToRun = new ServiceBase[]
{
new StockInfoService()
};
ServiceBase.Run(ServicesToRun);
#if (!DEBUG)
ServiceBase[] ServicesToRun = new ServiceBase[] { new SqlBackupService() };
ServiceBase.Run(ServicesToRun);
#else
StockInfoService service = new StockInfoService();
service.OnStart();
System.Threading.Thread.Sleep(System.Threading.Timeout.Infinite);
#endif
}
Step 2 - In Service.cs change your OnStart(string[] args) method without parameter one. (I commended mine.)
public void OnStart()
//protected override void OnStart(string[] args)
{
**Do your thing.
}
Step 3 - Simply hit Start (F5) and debug your code.