Powershell scripts to Extract, import and deploy SharePoint farm solutions

When you are maintaining SharePoint Farm, you might often want to be able to extract all SharePoint solution in the farm, import it back and deploy it.

I have seen such requirements during the migration, creation or maintenance of various environments like Pre-Prod, production etc.
After searching it on Internet, here are the 3 powershell scripts I have found:

Extract all the farm solutions:

(Get-SPFarm).Solutions | ForEach-Object{$var = "C:\<LocationUWantToStoreWSP>\" + $_.Name; $_.SolutionFile.SaveAs($var)}

 
Import all the farm solutions:

Get-ChildItem | ForEach-Object{Add-SPSolution -LiteralPath $_.Fullname}

Deploy all solutions to farm:

Get-SPSolution | ForEach-Object {If ($_.ContainsWebApplicationResource -eq $False) {Install-SPSolution -Identity $_ -GACDeployment} else {Install-SPSolution -Identity $_ -AllWebApplications -GACDeployment}}