Superstar Shay Levy recently wrote a blog article, Module Manifest Gotcha<\/A> . He was exploring the various options that the Module Manifest<\/A> provides and saw what he thought was a problem with using the PowerShellHostVersion key. <\/P>\n The \u201cgotcha\u201d here is that there are LOTS of PowerShell Hosts: PowerShell.exe, Powershell_ISE.exe, PowerGUI<\/A>, Sapien\u2019s PrimalScript<\/A>, PowerShellPlus<\/A> and others (apologizes in advance to those I forgot to mention). Shay created a manifest with PowerShellHostVersion = \u201c2.0\u201d and it worked fine with PowerShell.exe but barfed when he imported it into PowerShell_ISE.exe (because that is Version 1.0).<\/P>\n Say concluded: <\/P>\n \u201cTo be on the safe side, do not set a value<\/STRONG> for \u2018PowerShellHostVersion\u2019.\u201d<\/EM><\/P><\/BLOCKQUOTE>\n That is almost, but not quite, right. To understand why we added this seemingly useless feature, you need to take a look at the other keys in the manifest ( HERE<\/A> ). There are about 15 keys you can specify there and in general, you can safely ignore most of them and everything will work fine. Most of these keys are put there to allow people that have specific requirements and would generate weird errors or unpredictable behavior if their requirements were not met. <\/P>\n Let\u2019s take an example. PowerShell_ISE<\/A> is our new Integrated Scripting Environment that we shipped with PowerShell V2. We are super excited with PowerShell_ISE but the fact of the matter is that it is a pretty lean tool without many features. Each of the tools I mentioned above blow the doors of PowerShell_ISE in terms of features (you should check them all out \u2013 they are great). We knew that there would be features that people needed that we were not delivering so we provided an extensibility mechanism, the PowerShell ISE Scripting Object Model<\/A>. People do all sorts of wonderful things with this. For instance, James Brundage created ISE_Pack which is part of the (Free) Windows 7 Resource kit PowerShell Pack<\/A>. This delivers a bunch of cool functions that only work with PowerShell_ISE (because they script against the PowerShell ISE Scripting Object). <\/P>\n So what what happens when you try to import this module into plain old PowerShell.exe where they won\u2019t work because it doesn\u2019t have the PowerShell scripting model: <\/P>\n PS> Import-Module isepack<\/STRONG> errrrr\u2026.. hmmm\u2026.. ooooookaaaaaay\u2026.. well that\u2019s<\/STRONG> embarrassing! <\/P>\n I just loaded a module that has exactly 0% chance of working in this environment and got no error message. Let\u2019s see what happens if I try to do one of the functions:<\/P>\n PS> <\/FONT>New-ScriptModuleFromCurrentLocation<\/FONT> Split-Path : Cannot bind argument to parameter ‘Path’ because it is null. Join-Path : Cannot bind argument to parameter ‘Path’ because it is null. Test-Path : Cannot bind argument to parameter ‘Path’ because it is null. Exception calling “WriteAllText” with “2” argument(s): “Empty path name is not legal.” You cannot call a method on a null-valued expression. PS><\/FONT><\/P>\n Ok \u2013 now I want to puke. <\/P>\n What James has done is to highlight the \u201cFormality Range\u201d aspect of PowerShell. When you are writing code for yourself, it can be as informal as you like. PowerShell doesn\u2019t get in you way with lots of extra steps or hurdles \u2013 you can GO GO GO. But \u2026 when you want to share it with the world, PowerShell provides incremental features to be more formal and thus more friendly to a wide range of usage scenarios. <\/P>\n What James should have done is to go into his manifest and change:<\/P>\n # Name of the Windows PowerShell host required by this module to<\/P>\n # Name of the Windows PowerShell host required by this module Once you do that and try to import the module for Powershell.exe (the console host), you get this error:<\/P>\n PS> Import-Module isepack Now that is an error message that even I can understand!<\/P>\n So where are we going with all of this? <\/P>\n As I mentioned the first version of Powershell_ISE is pretty lean but we might go add more features in a future version. Let\u2019s imagine that James releases a new version of ISEPACK with a ton of new features that use the new PowerShell_ISE features. Since he added PowerShellHostName = ‘Windows PowerShell ISE Host’, we know that it will only load in the PowerShell_ISE but what happens if someone tries to load it into V1 of Powershell_ISE? We are going to be back to the same horrible experience of it loading OK only to fail in some random manner when I try to use one of it\u2019s features. <\/P>\n But wait wait! # Name of the Windows PowerShell host required by this module # Minimum version of the Windows PowerShell host required by this module Then if you loaded it into V3, it would work and if you tried to load it into V1, it would give you a nice error message. <\/P>\n PS> Import-Module ISEPACK<\/STRONG> <\/FONT><\/P>\n And now you know why we added something silly like PowerShellVersionHost to manifests. Shay- thanks for bringing the topic up. It gave me an opportunity to explain what is going on and it clearly demonstrates that we need to beef up our documentation. We delivered SO MANY new functions in V2, that we have a lot of documentation to write.<\/P>\n Experiment! Enjoy! Engage! <\/P>\n Jeffrey Snover [MSFT] Superstar Shay Levy recently wrote a blog article, Module Manifest Gotcha . He was exploring the various options that the Module Manifest provides and saw what he thought was a problem with using the PowerShellHostVersion key. PowerShellHostVersion key Specifies the minimum version of the Windows PowerShell host program that works with the module. The \u201cgotcha\u201d […]<\/p>\n","protected":false},"author":600,"featured_media":13641,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[206,244,264,23],"class_list":["post-3181","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-powershell","tag-isepack","tag-powergui","tag-powershell-plus","tag-sapien"],"acf":[],"blog_post_summary":" Superstar Shay Levy recently wrote a blog article, Module Manifest Gotcha . He was exploring the various options that the Module Manifest provides and saw what he thought was a problem with using the PowerShellHostVersion key. PowerShellHostVersion key Specifies the minimum version of the Windows PowerShell host program that works with the module. The \u201cgotcha\u201d […]<\/p>\n","_links":{"self":[{"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/posts\/3181","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/users\/600"}],"replies":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/comments?post=3181"}],"version-history":[{"count":0,"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/posts\/3181\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/media\/13641"}],"wp:attachment":[{"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/media?parent=3181"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/categories?post=3181"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/powershell\/wp-json\/wp\/v2\/tags?post=3181"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}\n
PS><\/FONT><\/P>\n
<\/FONT><\/STRONG>Split-Path : Cannot bind argument to parameter ‘Path’ because it is null.
At C:\\Users\\jsnover\\Documents\\WindowsPowerShell\\Modules\\isepack\\New-ScriptModuleFromCurrentLocation.ps1:16 char:27
+ $location = Split-Path <<<< $psise.CurrentFile.FullPath
+ CategoryInfo : InvalidData: (:) [Split-Path], ParameterBindingValidationException
+ FullyQualifiedErrorId : ParameterArgumentValidationErrorNullNotAllowed,Microsoft.PowerShell.Commands.SplitPathCo
mmand <\/FONT><\/P>\n
At C:\\Users\\jsnover\\Documents\\WindowsPowerShell\\Modules\\isepack\\New-ScriptModuleFromCurrentLocation.ps1:17 char:31
+ $locationName = Split-Path <<<< $location -Leaf
+ CategoryInfo : InvalidData: (:) [Split-Path], ParameterBindingValidationException
+ FullyQualifiedErrorId : ParameterArgumentValidationErrorNullNotAllowed,Microsoft.PowerShell.Commands.SplitPathCo
mmand <\/FONT><\/P>\n
At C:\\Users\\jsnover\\Documents\\WindowsPowerShell\\Modules\\isepack\\New-ScriptModuleFromCurrentLocation.ps1:22 char:28
+ $modulePath = Join-Path <<<< $location “$locationName.psm1”
+ CategoryInfo : InvalidData: (:) [Join-Path], ParameterBindingValidationException
+ FullyQualifiedErrorId : ParameterArgumentValidationErrorNullNotAllowed,Microsoft.PowerShell.Commands.JoinPathCom
mand <\/FONT><\/P>\n
At C:\\Users\\jsnover\\Documents\\WindowsPowerShell\\Modules\\isepack\\New-ScriptModuleFromCurrentLocation.ps1:23 char:18
+ if (Test-Path <<<< -ErrorAction SilentlyContinue $modulePath) {
+ CategoryInfo : InvalidData: (:) [Test-Path], ParameterBindingValidationException
+ FullyQualifiedErrorId : ParameterArgumentValidationErrorNullNotAllowed,Microsoft.PowerShell.Commands.TestPathCom
mand <\/FONT><\/P>\n
At C:\\Users\\jsnover\\Documents\\WindowsPowerShell\\Modules\\isepack\\New-ScriptModuleFromCurrentLocation.ps1:26 char:28
+ [IO.File]::WriteAllText <<<< ($modulePath, $text)
+ CategoryInfo : NotSpecified: (:) [], MethodInvocationException
+ FullyQualifiedErrorId : DotNetMethodException <\/FONT><\/P>\n
At C:\\Users\\jsnover\\Documents\\WindowsPowerShell\\Modules\\isepack\\New-ScriptModuleFromCurrentLocation.ps1:27 char:42
+ $psise.CurrentPowerShellTab.Files.Add <<<< ($modulePath)
+ CategoryInfo : InvalidOperation: (Add:String) [], RuntimeException
+ FullyQualifiedErrorId : InvokeMethodOnNull<\/FONT><\/P>\n
PowerShellHostName = ”<\/FONT><\/P>\n
PowerShellHostName = ‘Windows PowerShell ISE Host’<\/FONT><\/P>\n
Import-Module : The name of the current PowerShell host is: ‘ConsoleHost’. The module ‘C:\\Users\\jsnover\\Documents\\Windo
wsPowerShell\\Modules\\isepack\\isepack.psd1′ requires the following PowerShell host: ‘Windows PowerShell ISE Host’.
At line:1 char:5
+ ipmo <<<< isepack -Force
+ CategoryInfo : ResourceUnavailable: (C:\\Users\\jsnove…ck\\isepack.psd1:String) [Import-Module], Invalid
OperationException
+ FullyQualifiedErrorId : Modules_InvalidPowerShellHostName,Microsoft.PowerShell.Commands.ImportModuleCommand<\/FONT><\/FONT><\/P>\n
Wouldn\u2019t it be great if James could specify that his new Module ONLY worked with V3 of PowerShell_ISE?
Wouldn\u2019t it be great if there was a way to add something like:<\/P>\n
PowerShellHostName = ‘Windows PowerShell ISE Host’<\/FONT><\/P>\n
PowerShellHostVersion = ‘3.0’<\/STRONG><\/FONT><\/P>\n
Import-Module : The current PowerShell host is: ‘Windows PowerShell ISE Host’ (version 2.0). The module ‘C:\\Users\\jsnover\\Documents\\WindowsPo
werShell\\Modules\\ISEPACK\\ISEPACK.psd1′ requires a minimum PowerShell host version of ‘3.0’ to execute.
At line:1 char:14
+ Import-Module <<<< ISEPACK -force
+ CategoryInfo : ResourceUnavailable: (C:\\Users\\jsnove…CK\\ISEPACK.psd1:String) [Import-Module], InvalidOperationException
+ FullyQualifiedErrorId : Modules_InsufficientPowerShellHostVersion,Microsoft.PowerShell.Commands.ImportModuleCommand<\/FONT><\/FONT><\/P>\n
It\u2019s almost like we are thinking this stuff out. \ud83d\ude42<\/P>\n
Distinguished Engineer
Visit the Windows PowerShell Team blog at: http:\/\/blogs.msdn.com\/PowerShell<\/A>
Visit the Windows PowerShell ScriptCenter at: http:\/\/www.microsoft.com\/technet\/scriptcenter\/hubs\/msh.mspx<\/A><\/P><\/p>\n","protected":false},"excerpt":{"rendered":"