Using WS-Man to invoke a Powershell Cmdlet

re: Using WS-Man to invoke a Powershell Cmdlet

Steve Lee [MSFT] — Thu, 27 Sep 2012 18:13:31 GMT

Now that Windows Server 2012 is out, my recommendation for you would to be use the Management OData IIS Extension (blogs.msdn.com/.../powershell-cmdlets-invocation-through-management-odata-using-wcf-client.aspx). This is a new feature designed around calling PowerShell through a REST interface.

re: Using WS-Man to invoke a Powershell Cmdlet

Barfi — Thu, 27 Sep 2012 13:19:50 GMT

Steve Lee: Thanks for the informative post !

We are performing a series of Powershell commands in batch mode. Objects are returned from one powershell command are to be used in the subsequent command. This if I run by embedding a batch script within args[3] or the commandline param, there will be a problem as all$variables will be substituted.

One option then is to run each command of the script as a separate "Command custom SOAP action".

1) In that case, is it possible to de-serialize all objects to text and then using the stderr+stdout of a command and again serialize the text into objects for the next command.

2) We have one more problem where when another powershell module is loaded in one "Command custom SOAP Action". We get an error - "Process is terminated due to StackOverflowException" as part of the output.

Are there any known restrictions in each Powershell shell EPR ? How to avoid this/handle this."

re: Using WS-Man to invoke a Powershell Cmdlet

Steve Lee [MSFT] — Wed, 09 May 2012 15:57:19 GMT

It appears that this Open Source project successfully implemented session key HTTP encryption: github.com/.../WinRM. I have not tried that Ruby client myself so I can't speak to it's quality.

re: Using WS-Man to invoke a Powershell Cmdlet

Steve Lee [MSFT] — Wed, 09 May 2012 15:55:53 GMT

For cross-platform, it'll probably be easier to enable HTTPS instead of trying to implement session key based encryption (although you could follow the spec here: msdn.microsoft.com/.../cc251574(v=PROT.10).aspx).

re: Using WS-Man to invoke a Powershell Cmdlet

Barak — Wed, 09 May 2012 07:50:20 GMT

Well, I want to upload a script (which may be generated/modified by my code first) and then execute it. I think I have the upload sorted (using Base64) and I expect the files to be fairly small, so the Base64 overhead should not be a huge problem. I can't use BITS since the client running this may not be running Windows - it's a cross-platform project.

The next thing I have to tackle is encryption. The remote windows machines have encryption enabled (over HTTP on port 5985) and use NTLM authentication. Is there a sample somewhere showing how to encrypt the messages?

re: Using WS-Man to invoke a Powershell Cmdlet

Steve Lee [MSFT] — Tue, 08 May 2012 17:02:40 GMT

You could certainly use this technique to transfer a file using base64 encoding. However, it won't perform very well since the binary file would go through several levels of encoding (even if you skip PowerShell and just use cmd.exe). Recommendation is to use BITS to transfer the file if possible which goes over HTTP. msdn.microsoft.com/.../aa362708(v=vs.85).aspx

If you could articulate your specific scenario further (assuming BITS is not something you are able to use), I could give you a better answer.

re: Using WS-Man to invoke a Powershell Cmdlet

Barak — Tue, 08 May 2012 07:41:53 GMT

Kind of late to be asking this, but is there any way to use the same technique to transfer a file from the client to the server? Maybe pass a base64 encoded string as a parameter somehow?

re: Using WS-Man to invoke a Powershell Cmdlet

Steve Lee [MSFT] — Wed, 23 Nov 2011 23:35:48 GMT

@JMD Software, I did some research and it appears this was a known issue in Win7/Win2k8R2. PowerShell is designed to not prompt if stdin is redirected (which would be the case via WinRS). So there is no way to use WinRS Protocol to establish an interactive PowerShell session.

re: Using WS-Man to invoke a Powershell Cmdlet

Steve Lee [MSFT] — Wed, 23 Nov 2011 22:54:24 GMT

@JMD Software, it seems that there may be a issue preventing an interactive PowerShell session via WinRS from working correctly. On my Win2k8R2 box, just using "winrs -r:foo powershell.exe", I'm able to observe the behavior I believe you are describing. Executing "winrs -r:foo cmd" works, but starting powershell.exe under that remote cmd session exhibits the same problem. Due to how PowerShell uses the console, it appears that it may not be possible to use WinRS protocol for interactive PowerShell and you may need to implement PSRP (msdn.microsoft.com/.../dd357801(v=PROT.10).aspx).

re: Using WS-Man to invoke a Powershell Cmdlet

JMD Software — Wed, 23 Nov 2011 20:11:47 GMT

I’ve been trying to get the interactive pattern to work so I can create a custom remote powershell client. When I invoke powershell with a script as argument, input and output work fine with multiple receive messages. But when I invoke powershell with a script and “-NoExit”, receive stops working as soon as the script is done executing. I can send the request, but it’s waiting on something and never returns a response. I can still send messages such as “del file.txt” and they are processed correctly, so it’s just the receive message that stops working. Same thing happens when I invoke powershell without any arguments, the copyright text is displayed, but after that receive never returns anything.

Any idea why I’m getting this behavior?

Best regards

Johan