Build-PSModule

This action "compiles" the module source code into a efficient PowerShell module that is ready to be published to the PowerShell Gallery.

This GitHub Action is a part of the PSModule framework. It is recommended to use the Process-PSModule workflow to automate the whole process of managing the PowerShell module.

Supported module types

• Script module type
• Manifest module type

Supported practices and principles

• PowerShellGallery Publishing Guidelines and Best Practices are followed as much as possible.

How it works

During the build process the following steps are performed:

1. Copies the source code of the module to an output folder.
2. Builds the module manifest file based of info on the GitHub repository and source code. Read the Module Manifest section for more information.
3. Builds the root module (.psm1) file by combining source code and adding automation into the root module file. Read the Root module section for more information.
4. Builds the module documentation using platyPS and comment based help in the source code. Read the Module documentation section for more information.

Usage

Name	Description	Required	Default
Name	Name of the module to process.	false
Path	Path to the folder where the modules are located.	false	src
ModulesOutputPath	Path to the folder where the built modules are outputted.	false	outputs/modules
DocsOutputPath	Path to the folder where the built docs are outputted.	false	outputs/docs

Root module

The root module file is the main file that is loaded when the module is imported. It is built from the source code files in the module folder in the following order:

1. Adds module headers from header.ps1.
2. Adds data loader automation that loads files from the data folder as variables in the module scope, if it exists. The variables are available using the ´$script:´ syntax.
3. Adds content from subfolders, in the order:
   • Init
   • Private
   • Public
   • *.ps1 on module root
4. Adds the Export-ModuleMember function to the end of the file, to make sure that only the functions, cmdlets, variables and aliases that are defined in the module are exported.

The root module in the src folder

The root module file that is included in the source files contains the same functionality but is not optimized for performance. The goal with this is to have a quick way to import and test the module without having to build it.

Module manifest

The module manifest file is the file that describes the module and its content. It is used by PowerShell to load the module and its prerequisites. The file also contains important metadata that is used by the PowerShell Gallery.

During the module manifest build process the following steps are performed:

1. Get the manifest file from the source code. Content from this file overrides any value that would be calculated based on the source code.
2. Find and set the RootModule based on filename and extension.
3. Set a temporary ModuleVersion, as this is set during the release process by Publish-PSModule.
4. Set the Author and CompanyName based on GitHub Owner.
5. Set the Copyright information based on a default text ((c) 2024 >>OwnerName<<. All rights reserved.) and adds either the Author, CompanyName or both (Author | CompanyName) when these are different.
6. Set the Description based on the GitHub repository description.
7. Set various properties in the manifest such as PowerShellHostName, PowerShellHostVersion, DotNetFrameworkVersion, ClrVersion, and ProcessorArchitecture. There is currently no automation for these properties.
8. Get the list of files in the module source folder and set the FileList property in the manifest.
9. Get the list of required assemblies (*.dll files) from the assemblies folder and set the RequiredAssemblies property in the manifest.
10. Get the list of nested modules (*.psm1 files) from the modules folder and set the NestedModules property in the manifest.
11. Get the list of scripts to process (*.ps1 files) from the classes and scripts folders and set the ScriptsToProcess property in the manifest. This ensures that the scripts are loaded to the caller session (parent of module session).
12. Get the list of types to process by searching for *.Types.ps1xml files in the entire module source folder and set the TypesToProcess property in the manifest.
13. Get the list of formats to process by searching for *.Format.ps1xml files in the entire module source folder and set the FormatsToProcess property in the manifest.
14. Get the list of DSC resources to export by searching for *.psm1 files in the resources folder and set the DscResourcesToExport property in the manifest.
15. Get the list of functions, cmdlets, aliases, and variables to export and set the respective properties in the manifest.
16. Get the list of modules by searching for all *.psm1 files in the entire module source folder, excluding the root module and set the ModuleList property in the manifest.
17. Gather information from source files to update RequiredModules, PowerShellVersion, and CompatiblePSEditions properties.
18. The following values are gathered from the GitHub repository:
    • Tags are generated from Repository topics in addition to compatability tags gathered from the source code.
    • LicenseUri is generated assuming there is a LICENSE file on the root of the repository.
    • ProjectUri is the URL to the GitHub repository
    • IconUri is generated assuming there is a icon.png file in the icon folder on the repository root.
19. ReleaseNotes currently not automated, but could be the PR description or release description.
20. PreRelease is not managed here, but is managed from Publish-PSModule
21. RequireLicenseAcceptance is not automated and defaults to false, and
22. ExternalModuleDependencies is currenlty not automated.
23. HelpInfoURI is not automated.
24. Create a new manifest file in the output folder with the gathered info above. This also generates a new GUID for the module.
25. Format the manifest file using the Set-ModuleManifest function from the Utilities module.

Linking the description to the module manifest file might show more how this works:

@{
    RootModule             = 'Utilities.psm1' # Get files from root of folder wher name is same as the folder and file extension is .psm1, .ps1, .psd1, .dll, .cdxml, .xaml. Error if there are multiple files that meet the criteria.
    ModuleVersion          = '0.0.1' # Set during release using Publish-PSModule.
    CompatiblePSEditions   = @() # Get from source files, REQUIRES -PSEdition <PSEdition-Name>, null if not provided.
    GUID                   = '<GUID>' # Generated when finally saving the manifest using New-ModuleManifest.
    Author                 = 'PSModule' # Get from GitHub Owner, else use info from source manifest file.
    CompanyName            = 'PSModule' # Get from GitHub Owner, else use info from source manifest file.
    Copyright              = '(c) 2024 PSModule. All rights reserved.' # Generated from the current year and Author and Company values.
    Description            = 'This is a module.' # Get from the repository description, else use info from source manifest file.
    PowerShellVersion      = '' # Get from source files, REQUIRES -Version <N>[.<n>], null if not provided.
    PowerShellHostName     = '' # Get from manifest file, null if not provided.
    PowerShellHostVersion  = '' # Get from manifest file, null if not provided.
    DotNetFrameworkVersion = '' # Get from manifest file, null if not provided.
    ClrVersion             = '' # Get from manifest file, null if not provided.
    ProcessorArchitecture  = '' # Get from manifest file, null if not provided.
    RequiredModules        = @() # Get from source files, REQUIRES -Modules <Module-Name> | <Hashtable> -> Need to be installed and loaded on build time. Will be installed in global session state during installtion.
    RequiredAssemblies     = @() # Get from assemblies\*.dll.
    ScriptsToProcess       = @() # Get from scripts\*.ps1 and classes\*.ps1 ordered by name. These are loaded to the caller session (parent of module session).
    TypesToProcess         = @() # Get from *.Types.ps1xml anywhere in the source module folder.
    FormatsToProcess       = @() # Get from *.Format.ps1xml anywhere in the source module folder.
    NestedModules          = @() # Get from modules\*.psm1.
    FunctionsToExport      = @() # Get from public\*.ps1.
    CmdletsToExport        = @() # Get from manifest file, @() if not provided.
    VariablesToExport      = @() # To be automated, currently adds '@()' to the manifest file.
    AliasesToExport        = '*' # To be automated, currently adds '*' to the manifest file.
    DscResourcesToExport   = @() # Get from resources\*.psm1.
    ModuleList             = @() # Get from listing all .\*.psm1 files - Informational only.
    FileList               = @() # Get from listing all .\* files - Informational only.
    PrivateData            = @{  # <https://learn.microsoft.com/en-us/powershell/gallery/concepts/package-manifest-affecting-ui?view=powershellget-2.x>
        PSData = @{
            Tags                       = @() # Get from repository topics + compatability tags collected from source files.
            LicenseUri                 = '' # Generate public link to .\LICENSE.
            ProjectUri                 = '' # Generate public link to GitHub Repository.
            IconUri                    = '' # Get from .\icon\icon.png.
            ReleaseNotes               = '' # Update during release -> PR description or release description.
            Prerelease                 = '' # Update during release -> uses a normalized version of the branch name.
            RequireLicenseAcceptance   = $false ## Get from manifest file, default is $false.
            ExternalModuleDependencies = @() # Get from source manifest file
            ExperimentalFeatures       = @( # Get from source manifest file
                @{
                    Name = "SomeExperimentalFeature"
                    Description = "This is an experimental feature."
                }
            )
        }
        OtherKeys = @{} # Get from manifest file
    }
    HelpInfoURI            = '' # Get from source manifest file
    DefaultCommandPrefix   = '' # Get from source manifest file
}

The module manifest in the src folder

The module manifest file that is included in the source files contains the same functionality but is not optimized for performance and does not automatically gather all the information that is gathered during the build process. The goal with this is to have a quick way to import and test the module without having to build it.

The source module manifest is also the only place where some of the values can be controlled. These values are typically difficult to calculate and are not automated.

Module documentation

The module documentation is built using platyPS and comment based help in the source code. The documentation is currently not published anywhere, but should be published to GitHub Pages in a future release.

Permissions

The action does not require any permissions.

Sources

Module manifest:

• about_Module_Manifests
• How to write a PowerShell module manifest
• New-ModuleManifest
• Update-ModuleManifest
• Package metadata values that impact the PowerShell Gallery UI
• PowerShellGallery Publishing Guidelines and Best Practices

Modules:

• PowerShell scripting performance considerations
• PowerShell module authoring considerations:

Documentation:

• platyPS reference
• PlatyPS overview
• about_Comment_Based_Help
• Supporting Updatable Help