Copy-IfNotPresent

copy-ifnotpresent.ps1

Function Copy-IfNotPresent {
    <#
        .SYNOPSIS
            Copy file only if not present at destination.
        .DESCRIPTION
            This is a one file at a time call. It's not meant to replace complex call like ROBOCOPY.
            Destination can be a file or folder. 
            If it's a folder, you can use -Container to force Folder creation when not exists.
            If it's a file, you can provide a different name.
        .LINK
            https://gist.github.com/pollusb/cd47b4afeda8edbf8943a8808c880eb8
        .AUTHOR
            Pollus Brodeur
    #>
    [CmdletBinding()]
    Param (
        [Parameter(Mandatory)]
        $FilePath,

        [Parameter(Mandatory)]
        [string]$Destination,

        [switch]$Container,

        [switch]$WhatIf
    )
    #region validations
    if ($FilePath -isnot [System.IO.FileInfo]){
        $File = Get-ChildItem $FilePath -File
    } else {
        $File = $FilePath
    }

    if (!$File.Count){
        Write-Warning "$FilePath no file found."
        return
    } elseif ($File.Count -gt 1) {
        Write-Warning "$FilePath must resolve to one file only."
        return
    }
    #endregion

    # Destination is a folder
    if ($Container -or (Test-Path -Path $Destination -PathType Container)) {
        if (!(Test-Path $Destination)) {
            New-Item -Path $Destination -ItemType Container | Out-Null
            Write-Verbose "Copy-IfNotPresent $Destination (is absent) creating folder"
        }
        $Destination += "\$($File.Name)"
    }
    
    # Destination is a file
    if (!(Test-Path $Destination)) {
        if ($WhatIf) {
            Write-Host "WhatIf:Copy-IfNotPresent $FilePath -> $Destination"
        } else {
            # Force creation of parent folder
            $Parent = Split-Path $Destination -Parent
            if (!(Test-Path $Parent)) { 
                New-Item $Parent -ItemType Container | Out-Null
                Write-Verbose "Copy-IfNotPresent $Parent (is absent) creating folder"
            }
            Copy-Item -Path $FilePath -Destination $Destination  
            Write-Verbose "Copy-IfNotPresent $FilePath -> $Destination (is absent) copying"
        }
    } else {
        Write-Verbose "Copy-IfNotPresent $Destination (is present) not copying"
    }
}