使用 PowerShell 获取 Git 配置

几周前，我正在教授 PowerShell 基础知识课程。临近周末，我们开始创建简单的脚本和函数。一天晚上下课后，我正在考虑给他们另一个例子，我正在使用 git 开发一个项目。在某些时候，当我意识到输出是结构化文本时，我正在查看我的 git 配置，可以轻松地将其转换为 PowerShell 输出，即对象。因此，我创建了一个快速函数，将 git 的文本输出转换为将对象写入管道的传统 PowerShell 函数。

现在，我意识到有许多 PowerShell 模块和工具可用于使用 git，我可以重新发明轮子。但它满足了我的教学需求，经过一番打磨，我想我会分享它。

#requires -version 5.0

Function Get-GitConfig {

<#
.SYNOPSIS
    Get git configuration settings
.DESCRIPTION
    Git stores configurations settings in a simple text file format. Fortunately, this file is structured and predictable. This command will process git configuration information into PowerShell friendly output.
.PARAMETER Scope
    Possible values are Global,Local or System
.PARAMETER Path
    Enter the path to a .gitconfig file. You can use shell paths like ~\.gitconfig
.EXAMPLE
PS C:\> Get-GitConfig
   
Scope  Category  Name         Setting
-----  --------  ----         -------
global filter    lfs          git-lfs clean -- %f
global filter    lfs          git-lfs smudge -- %f
global filter    lfs          true
global user      name         Art Deco
global user      email        [email 
global gui       recentrepo   C:/Scripts/Gen2Tools
global gui       recentrepo   C:/Scripts/PSVirtualBox
global gui       recentrepo   C:/Scripts/FormatFunctions
global core      editor       powershell_ise.exe
global core      autocrlf     true
global core      excludesfile ~/.gitignore
global push      default      simple
global color     ui           true
global alias     logd         log --oneline --graph --decorate
global alias     last         log -1 HEAD
global alias     pushdev      !git checkout master && git merge dev && git push && git checkout dev
global alias     st           status
global alias     fp           !git fetch && git pull
global merge     tool         kdiff3
global mergetool kdiff3       'C:/Program Files/KDiff3/kdiff3.exe' $BASE $LOCAL $REMOTE -o $MERGED

Getting global configuration settings

.EXAMPLE
PS C:\> Get-GitConfig -scope system | where category -eq 'filter'

Scope  Category Name Setting
-----  -------- ---- -------
system filter   lfs  git-lfs clean -- %f
system filter   lfs  git-lfs smudge -- %f
system filter   lfs  git-lfs filter-process
system filter   lfs  true

Get system configuration and only git filters.

.EXAMPLE
PS C:\> Get-GitConfig -path ~\.gitconfig | format-table -groupby category -property Name,Setting

Get settings from a configuration file and present in a grouped, formatted table.

.INPUTS
    none
.OUTPUTS
    [pscustomobject]
.NOTES
    The command assumes you have git installed. Otherwise, why would you be using this?

    Last updated: 11 May, 2018
.LINK
    git
#>

    [CmdletBinding(DefaultParameterSetName = "default")]
    [OutputType([PSCustomObject])]
    Param (
        [Parameter(Position = 0, ParameterSetName = "default")]
        [ValidateSet("Global", "System", "Local")]
        [string[]]$Scope = "Global",
        [Parameter(ParameterSetName = "file")]
        #the path to a .gitconfig file which must be specified if scope if File
        [ValidateScript( {Test-Path $_})]
        [Alias("config")]
        [string]$Path
    )
    
    Begin {
        Write-Verbose "Starting $($myinvocation.MyCommand)"
        if ($path) {
            #convert path value to a complete file system path
            $Path = Convert-Path -Path $path
        }
        #internal helper function
        function _process {
            [cmdletbinding()]
            Param(
                [scriptblock]$scriptblock,
                [string]$Scope
            )

            Write-Verbose "Invoking $($scriptblock.tostring())"
            #invoke the scriptblock and save the text output
            $data = Invoke-Command -scriptblock $scriptblock
        
            #split each line of the config on the = sign
            #and add to the hashtable
            foreach ($line in $data) {
                $split = $line.split("=")
                #split the first element again to get the category and name
                $sub = $split[0].split(".")
                [PSCustomObject]@{
                    Scope    = $scope
                    Category = $sub[0]
                    Name     = $sub[1]
                    Setting  = $split[1]
                }
            } #foreach line
        } # _process
    } #begin
    
    Process {

        if ($PSCmdlet.ParameterSetName -eq 'file') {
            Write-Verbose "Getting config from $path"
            $get = [scriptblock]::Create("git config --file $path --list")
            #call the helper function
            _process -scriptblock $get -scope "File"
                        
        }
        else {
            foreach ($item in $Scope) {
                Write-Verbose "Getting $item config"
                #the git command is case sensitive so make the scope
                #lower case
                $item = $item.tolower()

                #create a scriptblock to run git config
                $get = [scriptblock]::Create("git config --$item --list")
        
                #call the helper function
                _process -scriptblock $get -Scope $item
           
            } #foreach scope
        } #else
    } #process
    
    End {
        Write-Verbose "Ending $($myinvocation.MyCommand)"
    } #end

} #end Get-GitConfig

#add an optional alias
Set-Alias -Name gcc -Value Get-GitConfig

默认行为是显示您的全局 git 配置。但您可以指定不同的范围。您还可以指定 gitconfig 文件的路径。因为对象被写入管道，您可以轻松识别 git 配置的不同部分。

一旦有了 PowerShell 命令，一切皆有可能。

如果您是 git 用户，我希望您能获取该函数的副本并让我知道您的想法。