Hi,
I wrote a nice debug function that provides the name of function from which it's called. The code is:
Function Write-Log {
$callerName = (Get-Variable MyInvocation -Scope 1).Value.MyCommand.Name
$stamp = (Get-Date).toString("yyyy/MM/dd HH:mm:ss")
$line = "$stamp [$level`]: $callerName $Message"
Write-Host $line -ForegroundColor $color
}
Works great when called from inside .ps1 script; however I started refactoring code so that some functions are moved to a .psm1 module - and this is where the function fails. Instead of printing the function name, it only provides the name of module.
How can I fix this function so that it only shows the function name, or scope & function name?
Thank you leeharvey1. Posting your suggestions as an answer to help other community members.
From your module, you can try using $callerName = "{0} - {1}:" -f (Get-PSCallStack)[1].Location, (Get-PSCallStack)[1].FunctionName.
Related
I load an "inline-type" in PowerShell like so:
$source = " some c# here "
$type = Add-Type -TypeDefinition $source -PassThru
$myvar = [MyClass]::new()
$myvar.Do()
How to call Write-Verbose from within the C# snippet, i.e., from the source in $source?
I only find examples on the Internet which perform WriteVerbose calls if the C# code contains a Cmdlet - which it does not in my case. Also I can find code how to call cmdlets in general, however, I don't want to create a new runspace, is there maybe any way to get the current runspace?
I found a solution, it is possible to pass a delegate to the C# code like so:
$writeVerboseDelegate = [Action[string]]{param($s) Write-Verbose $s; }
...
$myvar = [MyClass]::new($writeVerboseDelegate)
I'm not certain what is wrong with this scriptlet.
I'm trying to break out functionality into several other functions (I have a programming background not a scripting one per se) and to me LOGICALLY the following should execute starting at the "main" function Test-SgnedMpsPackage, accepting the various optional parameters (the script is not yet complete) then when the function Check-Path is called, that is run, then work would resume in the original calling function.
Am I missing something here?
On a side note, how does one return a value to the calling function? a simple return?
function CheckPath($path)
{
if ( test-path -Path $path )
{ Write-Host "{0} confirmed to exist." -f $path }
else
{ Write-Host "{0} DOES NOT exis.\nPlease check and run the script again" -f $path }
exit { exit }
}
function Test-SignedMpsPackage
{
Param(
[string] $PkgSource,
[string] $SigSource,
[string] $Destination
)
Process
{
#Check that both files exist
Write-Host "Check for file existence..."
CheckPath($PkgSource)
CheckPath($SigSource)
#retrieve signatures from file
}
}
Unlike C, C++ or C# there is no "main" entry point function. Any script at the top level - outside of a function - executes. You have defined two functions above but you haven't called either one. You need to do something like this:
function Test-SignedMpsPackage
{
...
}
Test-SignedMpsPackage params
Also as mentioned by #Bill_Stewart, you call your defined functions just like you call PowerShell commands - arguments are space separated and you don't use parens except to evaluate an expression inside the parens.
As for returning a value from a function, any output (Output stream) not captured by assigning to a variable or being redirected to a file is automatically part of the function's output. So I would modify your CheckPath function to this:
function CheckPath($path)
{
if (Test-Path -Path $path) {
Write-Verbose "{0} confirmed to exist." -f $path
$true
}
else {
Write-Verbose "{0} DOES NOT exist.\nPlease check and run the script again" -f $path
$false
}
}
You can use Write-Host as you had before but sometimes, perhaps in a script, you don't want to see the extra output. That is where Write-Verbose comes in handy. Set $VerbosePreference = 'Continue' to see the verbose output.
I have two Powershell files, a module and a script that calls the module.
Module: test.psm1
Function Get-Info {
$MyInvocation.MyCommand.Name
}
Script: myTest.ps1
Import-Module C:\Users\moomin\Documents\test.psm1 -force
Get-Info
When I run ./myTest.ps1 I get
Get-Info
I want to return the name of the calling script (test.ps1). How can I do that?
Use PSCommandPath instead in your module:
Example test.psm1
function Get-Info{
$MyInvocation.PSCommandPath
}
Example myTest.ps1
Import-Module C:\Users\moomin\Documents\test.psm1 -force
Get-Info
Output:
C:\Users\moomin\Documents\myTest.ps1
If you want only the name of the script that could be managed by doing
GCI $MyInvocation.PSCommandPath | Select -Expand Name
That would output:
myTest.ps1
I believe you could use the Get-PSCallStack cmdlet, which returns an array of stack frame objects. You can use this to identify the calling script down to the line of code.
Module: test.psm1
Function Get-Info {
$callstack = Get-PSCallStack
$callstack[1].Location
}
Output:
myTest.ps1: Line 2
Using the $MyInvocation.MyCommand is relative to it's scope.
A simple example (Of a script located : C:\Dev\Test-Script.ps1):
$name = $MyInvocation.MyCommand.Name;
$path = $MyInvocation.MyCommand.Path;
function Get-Invocation(){
$path = $MyInvocation.MyCommand.Path;
$cmd = $MyInvocation.MyCommand.Name;
write-host "Command : $cmd - Path : $path";
}
write-host "Command : $cmd - Path : $path";
Get-Invocation;
The output when running .\c:\Dev\Test-Script.ps1 :
Command : C:\Dev\Test-Script.ps1 - Path : C:\Dev\Test-Script.ps1
Command : Get-Invocation - Path :
As you see, the $MyInvocation is relative to the scoping. If you want the path of your script, do not enclose it in a function. If you want the invocation of the command, then you wrap it.
You could also use the callstack as suggested, but be aware of scoping rules.
I used this today after trying a couple of techniques.
$scriptPath = split-path -parent $MyInvocation.MyCommand.Definition
$ScriptName = $MyInvocation.MyCommand | select -ExpandProperty Name
Invoke-Expression ". $Script\$ScriptName"
To refer to the invocation info of the calling script, use:
#(Get-PSCallStack)[1].InvocationInfo
e.g.:
#(Get-PSCallStack)[1].InvocationInfo.MyCommand.Name
This provides the script path with trailing backslash as one variable and the script name as another.
The path works with Powershell 2.0 and 3.0 and 4.0 and probably 5.0
Where with Posershell $PSscriptroot is now available.
$_INST = $myinvocation.mycommand.path.substring(0,($myinvocation.mycommand.path.length - $MyInvocation.mycommand.name.length))
$_ScriptName = $myinvocation.mycommand.path.substring($MyInvocation.MyCommand.Definition.LastIndexOf('\'),($MyInvocation.mycommand.name.length +1))
$_ScriptName = $_ScriptName.TrimStart('\')
If you want a more reusable approach, you can use:
function Get-CallingFileName
{
$cStack = #(Get-PSCallStack)
$cStack[$cStack.Length-1].InvocationInfo.MyCommand.Name
}
The challenge I had was having a function that could be reused within the module. Everything else assumed that the script was calling the module function directly and if it was removed even 1 step, then the result would be the module file name. If, however, the source script is calling a function in the module which is, in turn, calling another function in the module, then this is the only answer I've seen that can ensure you're getting the source script info.
Of course, this approach is based on what #iRon and #James posted.
For you googlers looking for quick copy paste solution,
here is what works in Powershell 5.1
Inside your module:
$Script = (Get-PSCallStack)[2].Command
This will output just the script name (ScriptName.ps1) which invoked a function located in module.
I use this in my module:
function Get-ScriptPath {
[CmdletBinding()]
param (
[string]
$Extension = '.ps1'
)
# Allow module to inherit '-Verbose' flag.
if (($PSCmdlet) -and (-not $PSBoundParameters.ContainsKey('Verbose'))) {
$VerbosePreference = $PSCmdlet.GetVariableValue('VerbosePreference')
}
# Allow module to inherit '-Debug' flag.
if (($PSCmdlet) -and (-not $PSBoundParameters.ContainsKey('Debug'))) {
$DebugPreference = $PSCmdlet.GetVariableValue('DebugPreference')
}
$callstack = Get-PSCallStack
$i = 0
$max = 100
while ($true) {
if (!$callstack[$i]) {
Write-Verbose "Cannot detect callstack frame '$i' in 'Get-ScriptPath'."
return $null
}
$path = $callstack[$i].ScriptName
if ($path) {
Write-Verbose "Callstack frame '$i': '$path'."
$ext = [IO.Path]::GetExtension($path)
if (($ext) -and $ext -eq $Extension) {
return $path
}
}
$i++
if ($i -gt $max) {
Write-Verbose "Exceeded the maximum of '$max' callstack frames in 'Get-ScriptPath'."
return $null
}
}
return $null
}
You can grab the automatic variable MyInvocation from the parent scope and get the name from there.
Get-Variable -Scope:1 -Name:MyInvocation -ValueOnly
I did a basic test to check to see if it would always just get the direct parent scope and it worked like a treat and is extremely fast as opposed to Get-PSCallStack
function ScopeTest () {
Write-Information -Message:'ScopeTest'
}
Write-nLog -Message:'nLog' -Type:110 -SetLevel:Verbose
ScopeTest
I have two questions here, why does the following function in a script not recognized when I run the script:
Script:
$pathN = Select-Folder
Write-Host "Path " $pathN
function Select-Folder($message='Select a folder', $path = 0) {
$object = New-Object -comObject Shell.Application
$folder = $object.BrowseForFolder(0, $message, 0, $path)
if ($folder -ne $null) {
$folder.self.Path
}
}
I get error:
The term 'Select-Folder' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try aga
in.
But if I load and run it in the Windows Powershell ISE, it will give me the error the first time, and then act like it has "registered" the function and work after that.
And in case it is a procedural issue, I have tried listing the function at the top with no better luck.
Note I have tried simple functions like:
Write-host "Say "
Hello
function Hello {
Write-host "hello"
}
With the same exact results/error, it complains that Hello is not function....
Also, it still won't every work just running the script in powershell (only in ISE after the first initial attempt).
You need to declare your Select-Folder function before you try to use it. The script is read from top to bottom, so on the first pass when you try to use Select-Folder it has no idea what that means.
When you load it into the Powershell ISE it'll find out what Select-Folder means on the first run, and it'll still know that the 2nd time you try to run it (so you won't get the error then).
So if you change your code to:
function Select-Folder($message='Select a folder', $path = 0) {
$object = New-Object -comObject Shell.Application
$folder = $object.BrowseForFolder(0, $message, 0, $path)
if ($folder -ne $null) {
$folder.self.Path
}
}
$pathN = Select-Folder
Write-Host "Path " $pathN
that should work each time you run it.
Note: PowerShell 1.0
I'd like to get the current executing PowerShell file name. That is, if I start my session like this:
powershell.exe .\myfile.ps1
I'd like to get the string ".\myfile.ps1" (or something like that). EDIT: "myfile.ps1" is preferable.
Any ideas?
I've tried to summarize the various answers here, updated for PowerShell 5:
If you're only using PowerShell 3 or higher, use $PSCommandPath
If want compatibility with older versions, insert the shim:
if ($PSCommandPath -eq $null) { function GetPSCommandPath() { return $MyInvocation.PSCommandPath; } $PSCommandPath = GetPSCommandPath }
This adds $PSCommandPath if it doesn't already exist.
The shim code can be executed anywhere (top-level or inside a function), though $PSCommandPath variable is subject to normal scoping rules (eg, if you put the shim in a function, the variable is scoped to that function only).
Details
There's 4 different methods used in various answers, so I wrote this script to demonstrate each (plus $PSCommandPath):
function PSCommandPath() { return $PSCommandPath }
function ScriptName() { return $MyInvocation.ScriptName }
function MyCommandName() { return $MyInvocation.MyCommand.Name }
function MyCommandDefinition() {
# Begin of MyCommandDefinition()
# Note: ouput of this script shows the contents of this function, not the execution result
return $MyInvocation.MyCommand.Definition
# End of MyCommandDefinition()
}
function MyInvocationPSCommandPath() { return $MyInvocation.PSCommandPath }
Write-Host ""
Write-Host "PSVersion: $($PSVersionTable.PSVersion)"
Write-Host ""
Write-Host "`$PSCommandPath:"
Write-Host " * Direct: $PSCommandPath"
Write-Host " * Function: $(PSCommandPath)"
Write-Host ""
Write-Host "`$MyInvocation.ScriptName:"
Write-Host " * Direct: $($MyInvocation.ScriptName)"
Write-Host " * Function: $(ScriptName)"
Write-Host ""
Write-Host "`$MyInvocation.MyCommand.Name:"
Write-Host " * Direct: $($MyInvocation.MyCommand.Name)"
Write-Host " * Function: $(MyCommandName)"
Write-Host ""
Write-Host "`$MyInvocation.MyCommand.Definition:"
Write-Host " * Direct: $($MyInvocation.MyCommand.Definition)"
Write-Host " * Function: $(MyCommandDefinition)"
Write-Host ""
Write-Host "`$MyInvocation.PSCommandPath:"
Write-Host " * Direct: $($MyInvocation.PSCommandPath)"
Write-Host " * Function: $(MyInvocationPSCommandPath)"
Write-Host ""
Output:
PS C:\> .\Test\test.ps1
PSVersion: 5.1.19035.1
$PSCommandPath:
* Direct: C:\Test\test.ps1
* Function: C:\Test\test.ps1
$MyInvocation.ScriptName:
* Direct:
* Function: C:\Test\test.ps1
$MyInvocation.MyCommand.Name:
* Direct: test.ps1
* Function: MyCommandName
$MyInvocation.MyCommand.Definition:
* Direct: C:\Test\test.ps1
* Function:
# Begin of MyCommandDefinition()
# Note this is the contents of the MyCommandDefinition() function, not the execution results
return $MyInvocation.MyCommand.Definition;
# End of MyCommandDefinition()
$MyInvocation.PSCommandPath:
* Direct:
* Function: C:\Test\test.ps1
Notes:
Executed from C:\, but actual script is C:\Test\test.ps1.
No method tells you the passed invocation path (.\Test\test.ps1)
$PSCommandPath is the only reliable way, but was introduced in PowerShell 3
For versions prior to 3, no single method works both inside and outside of a function
While the current Answer is right in most cases, there are certain situations that it will not give you the correct answer. If you use inside your script functions then:
$MyInvocation.MyCommand.Name
Returns the name of the function instead name of the name of the script.
function test {
$MyInvocation.MyCommand.Name
}
Will give you "test" no matter how your script is named.
The right command for getting the script name is always
$MyInvocation.ScriptName
this returns the full path of the script you are executing. If you need just the script filename than this code should help you:
split-path $MyInvocation.PSCommandPath -Leaf
If you only want the filename (not the full path) use this:
$ScriptName = $MyInvocation.MyCommand.Name
Try the following
$path = $MyInvocation.MyCommand.Definition
This may not give you the actual path typed in but it will give you a valid path to the file.
beware:
Unlike the $PSScriptRoot and $PSCommandPath automatic variables, the
PSScriptRoot and PSCommandPath properties of the $MyInvocation automatic
variable contain information about the invoker or calling script, not the
current script.
e.g.
PS C:\Users\S_ms\OneDrive\Documents> C:\Users\SP_ms\OneDrive\Documents\DPM ...
=!C:\Users\S_ms\OneDrive\Documents\DPM.ps1
...where DPM.ps1 contains
Write-Host ("="+($MyInvocation.PSCommandPath)+"!"+$PSCommandPath)
If you are looking for the current directory in which the script is being executed, you can try this one:
$fullPathIncFileName = $MyInvocation.MyCommand.Definition
$currentScriptName = $MyInvocation.MyCommand.Name
$currentExecutingPath = $fullPathIncFileName.Replace($currentScriptName, "")
Write-Host $currentExecutingPath
As noted in previous responses, using "$MyInvocation" is subject to scoping issues and doesn't necessarily provide consistent data (return value vs. direct access value). I've found that the "cleanest" (most consistent) method for getting script info like script path, name, parms, command line, etc. regardless of scope (in main or subsequent/nested function calls) is to use "Get-Variable" on "MyInvocation"...
# Get the MyInvocation variable at script level
# Can be done anywhere within a script
$ScriptInvocation = (Get-Variable MyInvocation -Scope Script).Value
# Get the full path to the script
$ScriptPath = $ScriptInvocation.MyCommand.Path
# Get the directory of the script
$ScriptDirectory = Split-Path $ScriptPath
# Get the script name
# Yes, could get via Split-Path, but this is "simpler" since this is the default return value
$ScriptName = $ScriptInvocation.MyCommand.Name
# Get the invocation path (relative to $PWD)
# #GregMac, this addresses your second point
$InvocationPath = ScriptInvocation.InvocationName
So, you can get the same info as $PSCommandPath, but a whole lot more in the deal. Not sure, but it looks like "Get-Variable" was not available until PS3 so not a lot of help for really old (not updated) systems.
There are also some interesting aspects when using "-Scope" as you can backtrack to get the names, etc. of the calling function(s). 0=current, 1=parent, etc.
Hope this is somewhat helpful.
Ref, https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.utility/get-variable
I would argue that there is a better method, by setting the scope of the variable $MyInvocation.MyCommand.Path:
ex> $script:MyInvocation.MyCommand.Name
This method works in all circumstances of invocation:
EX:
Somescript.ps1
function printme () {
"In function:"
( "MyInvocation.ScriptName: " + [string]($MyInvocation.ScriptName) )
( "script:MyInvocation.MyCommand.Name: " + [string]($script:MyInvocation.MyCommand.Name) )
( "MyInvocation.MyCommand.Name: " + [string]($MyInvocation.MyCommand.Name) )
}
"Main:"
( "MyInvocation.ScriptName: " + [string]($MyInvocation.ScriptName) )
( "script:MyInvocation.MyCommand.Name: " + [string]($script:MyInvocation.MyCommand.Name) )
( "MyInvocation.MyCommand.Name: " + [string]($MyInvocation.MyCommand.Name) )
" "
printme
exit
OUTPUT:
PS> powershell C:\temp\test.ps1
Main:
MyInvocation.ScriptName:
script:MyInvocation.MyCommand.Name: test.ps1
MyInvocation.MyCommand.Name: test.ps1
In function:
MyInvocation.ScriptName: C:\temp\test.ps1
script:MyInvocation.MyCommand.Name: test.ps1
MyInvocation.MyCommand.Name: printme
Notice how the above accepted answer does NOT return a value when called from Main. Also, note that the above accepted answer returns the full path when the question requested the script name only. The scoped variable works in all places.
Also, if you did want the full path, then you would just call:
$script:MyInvocation.MyCommand.Path
A short demonstration of #gregmac's (excellent and detailed) answer, which essentially recommends $PSCommandPath as the only reliable command to return the currently running script where Powershell 3.0 and above is used.
Here I show returning either the full path or just the file name.
Test.ps1:
'Direct:'
$PSCommandPath # Full Path
Split-Path -Path $PSCommandPath -Leaf # File Name only
function main () {
''
'Within a function:'
$PSCommandPath
Split-Path -Path $PSCommandPath -Leaf
}
main
Output:
PS> .\Test.ps1
Direct:
C:\Users\John\Documents\Sda\Code\Windows\PowerShell\Apps\xBankStatementRename\Test.ps1
Test.ps1
Within a function:
C:\Users\John\Documents\Sda\Code\Windows\PowerShell\Apps\xBankStatementRename\Test.ps1
Test.ps1
Did some testing with the following script, on both PS 2 and PS 4 and had the same result. I hope this helps people.
$PSVersionTable.PSVersion
function PSscript {
$PSscript = Get-Item $MyInvocation.ScriptName
Return $PSscript
}
""
$PSscript = PSscript
$PSscript.FullName
$PSscript.Name
$PSscript.BaseName
$PSscript.Extension
$PSscript.DirectoryName
""
$PSscript = Get-Item $MyInvocation.InvocationName
$PSscript.FullName
$PSscript.Name
$PSscript.BaseName
$PSscript.Extension
$PSscript.DirectoryName
Results -
Major Minor Build Revision
----- ----- ----- --------
4 0 -1 -1
C:\PSscripts\Untitled1.ps1
Untitled1.ps1
Untitled1
.ps1
C:\PSscripts
C:\PSscripts\Untitled1.ps1
Untitled1.ps1
Untitled1
.ps1
C:\PSscripts
This can works on most powershell versions:
(& { $MyInvocation.ScriptName; })
This can work for Scheduled Job
Get-ScheduledJob |? Name -Match 'JOBNAMETAG' |% Command