en-US/about_PSDepend.help.txt

TOPIC
    about_PSDepend

SHORT DESCRIPTION
    PSDepend is a module to simplify dependency handling

DETAILED DESCRIPTION
    PSDepend is a module to simplify dependency handling

    Think of this like a simplified (Ruby) Bundler, or (Python) pip requirements files

    Terminology and concepts
    ========================
    There are three primary concepts:

        *.depend.psd1 files: PSD1 files that tell PSDepend what you want to install

        Dependency Type: These define how to actually install something.
                                Each type is associated with a script.
                                The default type is PSGalleryModule.
                                This is extensible.

        Deployment Script: These are scripts associated to a particular dependency type.
                                They tell PSDepend how to install a dependency type.
                                All should accept a 'Dependency' parameter.
                                For example, the PSGalleryModule script uses PowerShellGet to find
                                and install any dependencies specified in a depend.psd1 file.


    Example use (*.PSDepend.ps1)
    ============================

    I want to install dependencies from C:\projectx\projectx.depend.psd1

        C:\projectx\projectx.depend.psd1 looks like this:

            @{
                psdeploy = @{
                    Version = '0.1.8'
                    Target = 'C:\ProjectX'
                    DependencyType = 'PSGalleryModule'
                }
                buildhelpers = @{
                    Target = 'CurrentUser'
                }
                pester = 'latest'
                psake = '4.6.0'
            }

        # Install dependencies
        cd C:\projectx
        Invoke-PSDepend

        # Alternatively
        Invoke-PSDepend -Path C:\projectx

    See about_PSDepend_Definitions for more information

    Learning about Dependency Scripts
    ================================
    PSDepend Dependency scripts each treat Dependency details (e.g. Name, Source, Version)
    differently. In some cases, they may have their own Parameters. For example,
    a PSGalleryModule has a Repository Parameter.

    It is up to authors of Dependency scripts to expose help for this information.

    A few tools can assist in finding more information:

    # List available PSDepend Types, and their DependencyScripts
    Get-PSDependType

    # Show comment-based help for the PSGalleryModule DependencyType:
    Get-PSDependType -DependencyType PSGalleryModule -ShowHelp

    By convention, the comment-based help DESCRIPTION field should indicate
    how Dependency details are handled. For example, here's PSGalleryModule:

        Relevant Dependency metadata:
            Name: The name for this module
            Version: Used to identify existing installs meeting this criteria, and as RequiredVersion for installation. Defaults to 'latest'
            Target: Used as 'Scope' for Install-Module. If this is a path, we use Save-Module with this path. Defaults to 'AllUsers'

    Lastly, DependencyType specific parameters should be included as parameters
    for Dependency scripts. For example, we can see the Repository parameter for PSGalleryModule:

        -Repository <String>
            PSRepository to download from. Defaults to PSGallery
        
            Required? false
            Position? 2
            Default value PSGallery

    Extending PSDepend
    ==================
    PSDepend is somewhat extensible. To add a new dependency type:

        Update PSDependMap.psd1 in the PSDepend root.

            The dependency type name is the root node.
            The script node defines what script to run for these dependency types
            The description is... not really used. But feel free to write one!

            For example, I might add support for PackageManagement, and include a long and shorthand way to name these:

              Package:
                Script: Package.ps1
                Description: Install packages via PackageManagement module

              PackageManagement:
                Script: Package.ps1
                Description: Install packages via PackageManagement module

        Create the associated script in PSDepend\PSDependScripts

            For example, I would create \\Path\To\PSDepend\PSDependScripts\Package.ps1

        Include a 'Dependency' parameter.

            See \\Path\To\PSDepend\PSDependScripts\PSGalleryModule.ps1 for an example

            Here's how I implement this:
                param(
                    [PSTypeName('PSDepend.Dependency')]
                    [psobject[]]$Dependency
                    ...

        Include details on how you use Dependency properties in the comment-based help DESCRIPTION field.
        
            See \\Path\To\PSDepend\PSDependScripts\PSGalleryModule.ps1 DESCRIPTION field for an example

        Include parameters and comment based help for any parameters you read from the Dependency Parameter property.

            See \\Path\To\PSDepend\PSDependScripts\PSGalleryModule.ps1 parameters and help for an example

        Update *.depend.ps1 schema as needed.

            Get-Dependency converts PSD1 files into a number of 'Dependency' objects.
            If you need other data included, you can extend the schema and reference the
            'Raw' property on the dependency objects: this contains the raw data from the psd1

SEE ALSO
    about_PSDepend_Definitions
    https://github.com/RamblingCookieMonster/PSDepend