download_script_from_github.ps1

Function Get-Script{
  param (
    [Parameter(Mandatory=$true)][string]$script,  # the name of the file (needs to be in repo root, otherwise tweak this function)
    [string]$owner = "my-username",               # repo owner (github username)
    [string]$repo = "my-repo",                    # name of repo
    [string]$branch = "master",
    [string]$outputDir = ""
  )
  
  # the raw page for the script
  $uri = "https://raw.githubusercontent.com/$owner/$repo/$branch/$script"  
  
  # choosing a default output directory if none specified
  if ($outputDir -like "") {
      $currentDir = Get-Location
      $outputDir = "$currentDir\$repo"
  }
  
  # ensuring the output directory exists
  if ((test-path $outputDir) -ne $true) {
    Write-Output "  Creating directory $outputDir"
    New-Item -ItemType "Directory" -Path $outputDir | Out-Null
  }
  
  # logging
  Write-Output "Downloading $script"
  Write-Output "  from: $uri"
  Write-Output "  to: $outputDir"
  
  # reading the page and saving to file
  Invoke-WebRequest -Uri $uri -OutFile $outFile -Verbose
}

# Example execution: 
# Get-Script -script "my-script.ps1"