Get SSL Certificate Expiry Date From URL

Get-SSLCertificateExpiryDateFromURL.ps1

function Get-SSLCertificateExpiryDetailsFromURL {
    param (
        [ValidateNotNullOrEmpty()]
        [string]$InputFilePath = ".\input.csv",

        [string]$OutputFilePath = ".\output.csv",

        [bool]$ExportToCsv = $true, # Control CSV export

        [int]$TimeoutMilliseconds = 20000, # Timeout duration in milliseconds

        [int]$MaxRetries = 3, # Number of retries for each request

        [int]$IntervalSeconds = 5 # Interval in seconds between each request
    )

    function Get-SSLCertificateExpiryDateFromURL {
        param (
            [string]$Url,
            [int]$Timeout,
            [int]$RetryCount,
            [int]$Interval
        )

        $attempt = 0
        while ($attempt -lt $RetryCount) {
            try {
                $uri = if (-not $Url.StartsWith("https://")) { "https://$Url" } else { $Url }
                $uri = New-Object System.Uri($uri)
                $request = [Net.HttpWebRequest][Net.WebRequest]::Create($uri)
                $request.Timeout = $Timeout
                $response = $request.GetResponse()

                $certificate = New-Object System.Security.Cryptography.X509Certificates.X509Certificate2($request.ServicePoint.Certificate)
                $expiryDate = $certificate.NotAfter
                $formattedExpiryDate = $expiryDate.ToString("dd-MM-yyyy")
                $daysLeft = ($expiryDate - [datetime]::Now).Days

                return @{ 
                    'DNSName' = $uri.Host; 
                    'ExpiryDate' = $formattedExpiryDate; 
                    'DaysLeft' = $daysLeft 
                }
            } catch {
                Write-Host "Attempt $($attempt + 1) failed for $Url : $_"
                $attempt++
                Start-Sleep -Seconds $Interval # Pause before retrying
            }
        }
        Write-Host "Error processing $Url after $RetryCount attempts."
        return $null
    }

    if (-not (Test-Path -Path $InputFilePath)) {
        Write-Error "Input file not found at path: $InputFilePath"
        return
    }

    $entries = Import-Csv -Path $InputFilePath
    if ($entries.Count -eq 0) {
        Write-Host "No entries found in the input file."
        return
    }

    $results = foreach ($entry in $entries) {
        if ([string]::IsNullOrWhiteSpace($entry.DNSName)) {
            Write-Host "Skipping empty DNSName entry."
            continue
        }

        $expiryDetails = Get-SSLCertificateExpiryDateFromURL -Url $entry.DNSName -Timeout $TimeoutMilliseconds -RetryCount $MaxRetries -Interval $IntervalSeconds
        if ($expiryDetails -ne $null) {
            [PSCustomObject]@{ 
                DNSName = $expiryDetails.DNSName; 
                FriendlyName = $entry.FriendlyName; 
                DaysLeft = $expiryDetails.DaysLeft; 
                ExpiryDate = $expiryDetails.ExpiryDate 
            }
        }
        Start-Sleep -Seconds $IntervalSeconds # Sleep after processing each URL
    }

    if ($ExportToCsv) {
        $results | Export-Csv -Path $OutputFilePath -NoTypeInformation
        Write-Host "SSL certificate details exported to $OutputFilePath"
    } else {
        $results
    }
}

Get-SSLCertificateExpiryDetailsFromURL -InputFilePath ".\input.csv" -OutputFilePath ".\output.csv" -ExportToCsv $false