Executing a shell command in a web service

Question

User-588761007 posted

Hi,

I've just started with ASP.net, but have been doing web work and OO programming for a while. I'm working off IIS7 on Windows Server 2008.

I want to execute a program on the server-side using a web service. This program reads in some text files, runs some code and writes the results to file. I'm trying to launch the (GAMS) program using a batch file containing the necessary shell command. Here's the contents of the .bat file:

gams c:\gams\stage1.gms idir C:\GAMS\inputs Wdir=C:\GAMS

When I launch the .bat file in windows a command window flashes up and the results file is written to disk. Excellent.

So, now I tried to execute this batch file using a simple ASP.net Web Service. Here's the code:

<%@ WebService Language="C#" class="HelloWorld" Debug="true"%>

using System.Web.Services;

[WebService(Namespace = "http://tempuri.org/")]
public class HelloWorld : WebService 
{ 
	[WebMethod] 
	public string ExecuteTest() 
	{ 
		System.Diagnostics.Process proc = new System.Diagnostics.Process();
		proc.StartInfo.FileName="C:\\GAMS\\GAMS_stage1.bat";
		proc.Start();
		return "bat file executed"; 
	} 
}

When I run this in a browser, I get the xml response:

  <?xml version="1.0" encoding="utf-8" ?> 
  <string xmlns="http://tempuri.org/">bat file executed</string> 

However, the GAMS program either never executes or something goes wrong as the output of the GAMS program is never written to disk. I presumed there was a permissions issue but I've given full control permissions to the NETWORK SERVICE user on the affected directories and I'm not seeing ACCESS DENIED messages in Process Monitor.

How do I know if the program executed at all? I believe that the program would be running on an invisible desktop so I can't see anything. I'm sure I probably need more code as well. I tried to add proc.WaitForEnd() for example, but that caused an error.

 

Any ideas?

 

Thanks for your help