Copy contents of a git repo (branch) to another similar (not connected) repo

copy-repo.ps1

<#
.SYNOPSIS
  Simple but useful script to copy "exported" git content from one repo (specific branch) to another repo
.DESCRIPTION
  Script allows copying from two different repos (different providers, between public and private repos, etc) by creating an
  archive (git archive) of a particular branch in one repo and extracting it into a cleaned destination folder 
  which is linked to another related but disconnected repo.
  
  This is particularly useful when you can't fork a public repo and make it private 
  (when dealing perhaps with repos that leverage both public and pre-release / unpublished software)

  ASSUMPTIONS

  The script assumes that the project name will be either no suffix (for a GitHub repo) or have the suffix .VSTS for the VSTS repo

  RESULTS

  Use your favourite source control tool (Team Explorer, SourceTree, etc) to see the result, review the changes 
  and commit to the destination repo

.PARAMETER Branch
  Name of branch you would like to copy from (Source Repository)
.PARAMETER Projects
  Array of local folder / projects to process. 
.PARAMETER ProjectsFolder
  Name of the root folder where source control projects are stored.
.PARAMETER Source
  Source repository (in this example it's either GitHub or VSTS)

.OUTPUTS
  git archive created will be extracted into the projectDestinationPath folder.
.NOTES
  Version:        1.0
  Author:         J.F. Larente
  Creation Date:  6/13/2019
  Purpose/Change: Initial script development
  
.EXAMPLE
  .\copy-repo.ps1 -Branch master -Projects @("Project.Name") -Source GitHub 
    This will git archive the content of the master branch for local project (folder) Project.Name and copy it to Project.Name.VSTS 
    into the currently selected branch.
    You can ensure the destination is on the correct branch by creating / switching branches before running the copy command.

    To perform the reverse operation:
  .\copy-repo.ps1 -Branch master -Projects @("Project.Name") -Source VSTS
      This will git archive the content of the master branch for local project (folder) Project.Name and copy it to Project.Name.VSTS 
    
    For multiple projects / repos:
  .\copy-repo.ps1 -Branch master -Projects @("Project.Name", "Project1.Name") -Source GitHub 
    Same assumptions apply with naming convention. Script will iterate through all projects specified.

#>
Param(
    [string]$Branch = "develop",
    [string[]]$Projects = @("Demo.Platform"),
    [string]$ProjectsFolder = "C:\projects",
    [ValidateSet('GitHub', 'VSTS')]
    [Parameter(Mandatory = $true)]
    [string]$Source
)
set-alias sz "$env:ProgramFiles\7-zip\7z.exe"
# Script assumes GitHub <-> VSTS although this can be any two repos. 
# .VSTS could be changed to .INTERNAL for example.
if ($Source -eq "VSTS") {
    $sourcePostFix = ".VSTS"
}
else {
    $destinationPostFix = ".VSTS"
}
foreach ($project in $Projects) {

    # Set the source and destination paths
    $projectSourcePath = (Join-Path $ProjectsFolder ( $project + $sourcePostFix))
    $projectDestinationPath = (Join-Path $ProjectsFolder (  $project + $destinationPostFix))
    
    # Clean existing folder first
    
    Set-Location $projectDestinationPath
    $exclude = @(".*", "other-file-pattern-to-exclude") #Excludes anything that starts with a . (important .git, .gitignore, etc)
    Get-ChildItem -Exclude $exclude | Remove-item -Recurse -Force #deletes all items except the exclude list from destination repo

    # Create an archive of the desired branch from the source repository
    Set-Location $projectSourcePath
    Write-Host ("Archiving {0} - {1} branch" -f $project, $Branch) -ForegroundColor Green
    $zipFileName = ($projectSourcePath + ".zip")
    git fetch
    git checkout $Branch
    git pull
    git archive --format=zip -o $zipFileName $Branch

    # Extract the contents of the archive to the destination directory
    Write-Host ("Extracting {0} to {1}" -f $zipFileName, $projectDestinationPath) -ForegroundColor Green
    sz x $zipFileName -o"$($projectDestinationPath)" -r -y -aoa -x!".gitignore"

    # Cleanup
    Remove-item $zipFileName

    Write-Host ("Copy of {0} Completed" -f $project)
}