GitHub actions pipeline to sign PowerShell scripts

SignPowerShell.yaml

name: Sign PowerShell Scripts
on:
  push

env:
  ARTIFACT_NAME: PowerShell.Workflows.ScriptSigning

jobs:
  sign_scripts:
    name: Sign and publish PowerShell scripts as pipeline artifacts
    runs-on: windows-2019
    steps:
      - name: Import code signing certificate
        shell: powershell
        run: |
          $pfxCertFilePath = Join-Path -Path $PSScriptRoot -ChildPath "CodeSigningCertificate.pfx"
          Set-Content -Value $([System.Convert]::FromBase64String($env:BASE64_PFX)) -Path $pfxCertFilePath -Encoding Byte
          $codeSigningCert = Import-PfxCertificate -FilePath $pfxCertFilePath -Password $($env:PFX_PASSWORD | ConvertTo-SecureString -AsPlainText -Force) -CertStoreLocation Cert:\CurrentUser\My
        env:
          BASE64_PFX: ${{ secrets.BASE64_PFX }}
          PFX_PASSWORD: ${{ secrets.PFX_PASSWORD }}
      - name: Check out repository
        uses: actions/checkout@v2
      - name: Sign PowerShell scripts
        shell: powershell
        run: |
          # remove git dir from checked out repo
          Get-ChildItem -Path "." -Filter ".git*" -Force | ForEach-Object {Remove-Item -Path $_.FullName -Recurse -Force}
          $scripts = Get-ChildItem -Path . -Filter "*.ps1" -Recurse -ErrorAction Stop
          # load cert
          $codeSigningCert = Get-ChildItem Cert:\CurrentUser\My -CodeSigningCert | Select-Object -First 1

          foreach ($script in $scripts) {
              try {
                    $scriptContent = Get-Content -Path $script.FullName
                    Write-Output "Signing script `"$($script.Name)`" with certificate `"$($codeSigningCert.Thumbprint)`""
                    # sign script
                    $null = Set-AuthenticodeSignature -Certificate $codeSigningCert -FilePath $script.FullName -TimestampServer "http://timestamp.comodoca.com/rfc3161"
              }
              catch {
                  Write-Error $_
              }
          }
      - name: Publish artifacts
        uses: actions/upload-artifact@v2
        with:
          name: ${{ env.ARTIFACT_NAME }}
          path: .