Pass argument into Powershell - powershell

I have a powershell script that completes some tasks in Active Directory and MS Exchange. I need to pass in the Active Directory username from our call logging system. Having the Call log system pass the argument is simple.
The problem i am facing is having powershell read the argument into a variable.
I will provide a proof of concept example.
Here is a sample command passing the argument into powershell.
C:\Users\UserName\Desktop\Test.ps1 -ADusername "Hello World"
Here is the sample script:
Param([string]$adusername)
$adusername
pause
I am Expecting the following output:
Hello World
Press Enter to continue...:
This is the actual output:
Press Enter to continue...:
Just wrapping my head around this core concept will help me immensely. I was unable to find any examples or tutorials that worked when applied to my scenario. I apologize if this is a duplicate post, couldnt find anything on this site as well.
EDIT: per request, this is my full script: http://pastebin.com/ktjpLQek

I think you will have much better luck if you avoid trying to use params and call the script exactly that way.
It is possible, but paramaters work better if you either inline the scriptfile like:
. .\scriptFile.ps1
function "Hello World"
Staying closer to what you are doing however, you should be using $args and calling PowerShell (the exe directly)
If you call your scriptfile like: (I used the runbox)
powershell c:\Path\Folder\Script.ps1 "Hello World!"
and then replace your Param([string]$adusername) with:
$adUserName = $args[0]
write-host $adUserName
Additionally, this should work for you (to dissect):
Param([string]$ad)
Write-Host $args[0]
Write-Host $ad
Read-Host
pause
Call the script with the path,
powershell c:\Path\Folder\Script.ps1 "Hello World!" $ad = "JSmith"
If this does not work, you should ensure that your execution policy is set correctly. Get-ExecutionPolicy will tell you the current level. For testing you can set it very low with Set-ExecutionPolicy unrestricted

Add the following to the top of your script.
Param(
[Parameter(Mandatory=$true)]
[string]$Euser
)
Write-Host "Deactivating $EUser"
Calling example after cd to the script directory
.\ScriptName.ps1 -Euser "FOO" # Tab auto completion works

The following in a new script works for me.
Param([string]$servers)
"You chose $servers"
PS C:\scripts> .\Untitled1.ps1 "this test"
You chose this test
PS C:\scripts>

Related

Why working script fails when running in the background?

I have such script (here simplified):
while ($true)
{
Write-Host "Looping..."
Write-Host "Looping..." 6>> trash.txt
Start-Sleep -s 1
}
when I run it directly it works, but when I run it in the background:
Start-Job { .\sleeper.ps1 }
for a second it is seen as Running but shortly after as Failed and indeed file "trash.txt" is not created at all, so even one iteration is not executed.
What is wrong here?
I think the main issue is around the $PWD and -FilePath param, but I will list some info on Write-Host too:
Start-Job should be run with the -FilePath parameter. This is because {} is a ScriptBlock object, which is by default taken by the -ScriptBlock parameter, which you do not want. Example solution to that line: Start-Job -FilePath ./script.ps1
The $PWD or present working directory is, by default, the home directory / user profile of the current user when executed in a PowerShell job (Linux: $HOME // Windows: $Home/Documents). You can test this by executing a job simply with that variable (it may be $ENV:PWD on Windows?). Either way, it is likely not the same as the directory you are executing this in. trash.txt is being made and appended to, but it is being made in a different directory than your current directory. You will want your script to explicitly include an absolute path to the file being created, or give the script parameters that allow you to input the path at execution. Here is another StackOverflow article where a user had similar struggles, with two good solutions where one uses $args in the script and another uses the -InitializationScript parameter of Start-Job to set the $PWD: PowerShell Start-Job Working Directory
Often, Write-Host is low-priority as a selected output vs. using Write-Output / Write-Verbose / Write-Warning / Write-Error. More information about this can be found here: https://www.jsnover.com/blog/2013/12/07/write-host-considered-harmful/ - though, newer versions of PowerShell have added an information stream which I believe may make Write-Host output more accessible. More information on streams can be found with help about_Redirection

Write-output when executing script in a wpf event script

I have a script that accepts lots of parameters and is fairly big. I've been asked to build a GUI for executing the script, so users can easily execute the script without making mistakes. So the idea was that the GUI script collects all the parameters, and then executes the script.
The "main" script uses write-output and start-transcript for logging to the shell and to a file. This also works.
But when I execute the script from the GUI script I'm not getting every output to the shell or to the log. I figured that this is because of write-output because Write-Host does work, but everywhere I go I hear people say that you shouldn't use write-host (for instance: https://youtu.be/SSJot1ycM70?t=24m1s).
So how do I get this to work?
Currently I use this to execute the script from the gui:
& $PSscriptroot\guitest2.ps1 -switchparam1:$localvar1 -switchparam2:$localvar2 -stringparam $localvar3
I have tried to run a new instance of powershell via cmd, but I don't seem to get this to work. I have also no idea how to "send" the parameters to the script this way.
Invoke-Expression 'cmd /c powershell.exe -file C:\...\script.ps1 -paramters.
or
Invoke-Expression 'cmd /c powershell.exe -command {C:\..\script.ps1 -paramters..}
The two scripts below do exactly what I want. But when I execute the script in a wpf event (ie after the start button has been pressed) the second script only shows the write-warning, write-error and write-host output, so not the write-output.
script1:
#gui script
$boolean = $true
$string = "test"
& $PSscriptroot\script2.ps1 -switch:$boolean -string $string
script2:
param(
[switch]$switch,
[string]$string
)
Start-Transcript
write-output "output"
write-host "host"
$a = "Variable"
$a
write-error "error"
Write-Warning "warning"
Write-Debug "debug"
Stop-Transcript
EDIT:
did some more testing. Apparently write-output completely doesn't work when called in a wpf event. For example:
$wpf.startButton.Add_Click({
write-output "This message is not shown"
})
Not sure if this is a bug or not
Write-Output passes an object through the pipeline to another command. Essentially the statement
Write-Output <expression>
is in many cases exactly identical to
<expression>
Other Write-* cmdlets behave a bit differently. In your case you have an event handler, which has no return value anyway. Your example is the same as
"This message is not shown"
or even
return "This message is not shown"
As the string is part of the return value of that script block, which no one ever looks at.
If you want output in the host application, use Write-Host. That's what it's for. Write-Output is something you rarely, if ever, need in a script.

Powershell Script not working out of ISE

I have a powershell Script that runs fine in the ISE, but when I run it directly from the .ps1 file it stops at this point:
Write-Host "Attempting to start FFMPEG Process with arguments:$ArgumentList::::" -ForegroundColor Green
Start-Process $SCRIPT:FFMPEGLocation $ArgumentList -Wait
I get the Write-Host printout, with the correct Argument List, but no window pops up for the start-process or anything. I made sure to use the SCRIPT scope variable for anything that is outside the function. It runs fine in ISE just not when I run it in Console. No errors either, and the $SCRIPT:FFMPEGLocation variable is a direct path to the exe to be executed.
Any help would be greatly appreciated, and if you need more let me know.
PSVersion 5.1.14393.1066
OSVersion 10.0.14393
As per comments, check the value passed to Start-Process to ensure it contains what you expect as the issue is likely to be with $SCRIPT:FFMPEGLocation.
The difference between the ISE and Console with regard to scope can be frustrating.
See this SuperUser post which explains the behaviour further
. You may also find this post helpful;
BartekB explains that F5 in the ISE actually dot-sources the script instead of calling it, and provides a function to run a clean session.
An alternative method which will also wait on the process that needs to be run:
& $EXE /arg 1 /arg 2 -etc 2>&1 | % { $_ }
This will execute the command and pass the args, redirect any errors to the output stream and then print that output (for some reason, I've had bad luck with actually getting output from commands)

Using read-host cmdlet when execute powershell script file in MSBuild

All , I am trying to execute a external power shell script file in the MSBuild. But every time when PS run the cmdlet Read-Host. The MSBuild seems stop. and doesn't prompt me to input . I don't know what happen to it . Seems the console is in deadlock..thanks.
The testloop.ps1 code is shown below.
$ErrorActionPreference = 'Stop'
$error.clear()
function GetAzureSubScription()
{
read-host "please input something :"
}
write-host "Get into script"
GetAzureSubScription
The MSBuild code is below (wrapped for clarity):
<Exec WorkingDirectory="$(MSBuildProjectDirectory)"
Command="$(windir)\system32\WindowsPowerShell\v1.0\powershell.exe -f
E:\Work\AutoDeploy\testloop.ps1" />
So yes, the console (just a minor point - powershell.exe does not run under cmd.exe - they are separate processes, but they both use a console window) window is hidden so it will appear to freeze when prompting for input. The simplest option here is to override the read-host function with a version that will prompt using a graphical window. Add the start of your script, add the following function:
# override the built in prompting, just for this script
function read-host($prompt) {
$x = 0; $y = 0;
add-type -assemblyname microsoft.visualbasic
[Microsoft.VisualBasic.Interaction]::InputBox($prompt,
"Interactive", "(default value)", $x, $y)
}
Now your script will be able to prompt for values. Also, you should run powershell.exe with the -noninteractive argument to catch any other places where you are accidentally calling interactive host functions. It will not stop the above function from working though.
The MSBuild Exec tasks starts cmd.exe and let that execute the command. MSbuild has to channel the writes to the console through since the cmd.exe window itself is invisible. It seems the writes do get through, but the reads do not. You can see the same effect if instead of calling powershell you exec a command like "del c:\temp\somefile.txt /p" which asks for confirmation. Although that way it doesn't block, but there is also no way of giving an answer.
That it does not handle reads properly is not that strange. It is a build script, so it should just build and not ask questions. My advice is to have the MSBuild script run without asking questions. If you really need to ask questions, then ask them before calling MSBuild.

Powershell window disappears before I can read the error message

When I call a Powershell script, how can I keep the called script from closing its command window. I'm getting an error and I'm sure I can fix it if I could just read the error.
I have a Powershell script that sends an email with attachment using the .NET classes. If I call the script directly by executing it from the command line or calling it from the Windows Scheduler then it works fine. If I call it from within another script (IronPython, if that matters) then it fails. All scenarios work fine on my development machine. (I really do have to get that "Works on My Machine" logo!) I've got the call to Powershell happening in a way that displays a command window and I can see a flicker of red just before it closes.
Sorry: Powershell 1.0, IronPython 1.1
Solution: powershell -noexit d:\script\foo.ps1
The -noexit switch worked fine. I just added it to the arguments I pass from IronPython. As I suspected, it's something that I can probably fix myself (execution policy, although I did temporarily set as unrestricted with no effect, so I guess I need to look deeper). I'll ask another question if I run into trouble with that.
Thanks to all for the help. I learned that I need to investigate powershell switches a little more closely, and I can see quite a few things that will prove useful in the future.
Try with the -noexit switch:
powershell -noexit d:\script\foo.ps1
You basically have 3 options to prevent the PowerShell Console window from closing, that I describe in more detail on my blog post.
One-time Fix: Run your script from the PowerShell Console, or launch the PowerShell process using the -NoExit switch. e.g. PowerShell -NoExit "C:\SomeFolder\SomeScript.ps1"
Per-script Fix: Add a prompt for input to the end of your script file. e.g. Read-Host -Prompt "Press Enter to exit"
Global Fix: Change your registry key to always leave the PowerShell Console window open after the script finishes running.
Here are the registry keys to modify for option #3:
Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\Applications\powershell.exe\shell\open\command]
#="\"C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\powershell.exe\" -NoExit \"& \\\"%1\\\"\""
[HKEY_CLASSES_ROOT\Microsoft.PowerShellScript.1\Shell\0\Command]
#="\"C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\powershell.exe\" -NoExit \"-Command\" \"if((Get-ExecutionPolicy ) -ne 'AllSigned') { Set-ExecutionPolicy -Scope Process Bypass }; & \\\"%1\\\"\""
See my blog for more information and a .reg file that will apply these registry changes automatically.
I've needed this before and usually I didn't want to modify the script (typically for scripts fired off from the Task Scheduler). I just wanted to see what was spit out to console.
All you need to do is just append a Read-Host command after the script invocation e.g.:
PowerShell.exe -command { .\foo.ps1; read-host "Press enter key to continue" }
BTW the problem with using Start-Transcript is that it doesn't capture EXE output. And any form of attempted logging in V1 and even V2 with the standard host will not capture the verbose, debug, progress or warning streams. You can only see these by viewing the associated host window.
One cheesy but effective way to capture all script output (stdout, stderr, verbose, warning, debug) is to use another host like cmd.exe e.g.:
cmd.exe /c powershell.exe "$pwd\foo.ps1" > foo.log
I am generaly fine with scripts autoclosing except when an error occurs, where I need to see the error. Assuming you have not changed $ErrorActionPreference away from the default 'Continue', then for the behaviour I described do this at the end of you script
if ($Error)
{
Pause
}
There is no ordinary Try...Catch construction in Powershell; however you can trap exceptions instead and react properly.
I.E:
Function Example() {
trap [Exception] {
write-host "We have an error!";
write-error $("ERROR: " + $_.Exception.Message);
sleep 30;
break;
}
write-host "Hello world!";
throw "Something very bad has happened!";
}
You can also simulate Try...Catch construction:
Function Example2() {
${
write-host "Our try clause...";
throw "...caused an exception! It hurts!";
}
trap [Exception] {
write-error $_.Exception.Message;
sleep 30;
continue;
}
Of course as soon as you will trap an exception, you can log it, sleep, or whatever you want with the error message. My examples just sleep, allowing you to read what happened, but it's much better to log all the errors. (The simplest way is to redirect them with >>).
Look also at:
http://huddledmasses.org/trap-exception-in-powershell/
A quick and dirty solution is to use CTRL+S to halt the scrolling of the display and CTRL+Q to resume it.
You have three options:
Do a catch in the script (if using
Powershell V2)
Write a dummy
script which catches and redirects
stdout which you can then access as a
variable from your IronPython script.
VBS/Wscript Intro An addition to
this is just liberally drop
Read-Host commands everywhere,
and hit return to page through.
Rather than outputting anything to the shell, wrap your powershell script in a second script that redirects all output to a log file.
PS C:> myscript.ps1 |Out-File myscript.log
Create run_ps_script.bat file containing
#PowerShell.exe -command "try { %1 } finally { read-host 'Press ENTER...' }"
and make it default program to open PowerShell scrips.
My solution was to execute the script with a command line from the console window instead of right-clicking the file -> execute with powershell.
The console keeps displaying the error messages,
even though the execution of the script ended.
Have you thought about redirecting stdout and stderr to a file ex:
./ascript.ps1 >logs 2>&1
Note: You can create wrapper script in powershell that calls your powershell script with all necessary redirections.
My .PS1 script ran fine from the Powershell console but when "double-clicking" or "right-click open with powershell" it would exhibit the 'open/close' problem.
The Fix for me was to rename the script folder to a Name Without Spaces.
Then it all worked - Windows couldn't deal with
"C:\This is my folder\myscript.ps1" but
"C:\This_is_my_folder\myscript.ps1" worked just fine
A couple more ideas...You could use the start-sleep cmdlet at the end of you script to give you enough time to review the error.
You might also be able to use start-transcript to record the session to a text file.