added DownloadWithRetry function

images/win/scripts/Installers/Install-SQLExpress.ps1

@@ -2,6 +2,7 @@
 ##  File:  Install-SQLExpress.ps1
 ##  Desc:  Install SQL Express for Windows
 ################################################################################
+Import-Module -Name ImageHelpers -Force;
 
 function Download-FullSQLPackage {
     param(
@@ -60,52 +61,14 @@ function Start-Installer {
     }
 }
 
-
-function Start-DownloadSQLExpress {
-    param(
-        [String]$InstallerUrl,
-        [String]$InstallerPath,
-        [int] $retries = 10
-    )
-    Write-Host "Downloading SQL Express web-installer from: $InstallerUrl"
-    # In case of any errors -try to download package several times
-    while($retries -gt 0)
-        {
-            try
-            {
-                Write-Host "Downloading SQL Express installer..."
-                (New-Object System.Net.WebClient).DownloadFile($InstallerUrl, $InstallerPath)
-                break
-            }
-            catch
-            {
-                Write-Host "There is an error during SQL Express downloading"
-                $_
-
-                $retries--
-
-                if ($retries -eq 0)
-                {
-                    Write-Host "File can't be downloaded"
-                    $_
-                    exit 1
-                }
-
-                Write-Host "Waiting 30 seconds before retrying. Retries left: $retries"
-                Start-Sleep -Seconds 30
-            }
-        }
-    Write-Host "SQL Express has been successfully downladed from the link: $InstallerUrl"
-}
 #default variables for functions.
 $installerUrl = "https://go.microsoft.com/fwlink/?linkid=866658"
-$installerPath = "${env:Temp}\SQL2019-SSEI-Expr.exe"
 $downloadPath = "C:\SQLEXPRESS2019"
 $setupPath = Join-Path $downloadPath "SQLEXPR_x64_ENU"
 #Set default location for proper script execution
 Set-Location -Path $downloadPath
 #Download installer for SQL Express
-Start-DownloadSQLExpress -InstallerUrl $installerUrl -InstallerPath $installerPath
+$installerPath = Start-DownloadWithRetry -Url "https://go.microsoft.com/fwlink/?linkid=866658" -Name SQL2019-SSEI-Expr.exe
 #Download full SQL Express package
 Download-FullSQLPackage -InstallerPath $installerPath
 #Unpack SQL Express Installer