Public/Invoke-Download.ps1
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function Invoke-Download { [CmdletBinding()] param( [Parameter(Position = 0, Mandatory = $true, ValueFromPipeline = $true)] [Alias('URI')] [ValidateNotNullOrEmpty()] [string]$URL, [Parameter(Position = 1)] [ValidateNotNullOrEmpty()] [string]$Destination = $PWD.Path, [Parameter(Position = 2)] [string]$FileName, [string[]]$UserAgent = @('Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.0.0 Safari/537.36', 'Googlebot/2.1 (+http://www.google.com/bot.html)'), [string]$TempPath = [System.IO.Path]::GetTempPath(), [switch]$IgnoreDate, [switch]$BlockFile, [switch]$NoClobber, [switch]$NoProgress, [switch]$PassThru ) begin { # Required on Windows Powershell only if ($PSEdition -eq 'Desktop') { Add-Type -AssemblyName System.Net.Http Add-Type -AssemblyName System.Web } # Enable TLS 1.2 in addition to whatever is pre-configured [Net.ServicePointManager]::SecurityProtocol = [Net.ServicePointManager]::SecurityProtocol -bor [Net.SecurityProtocolType]::Tls12 # Create one single client object for the pipeline $HttpClient = New-Object System.Net.Http.HttpClient } process { Write-Verbose "Requesting headers from URL '$URL'" foreach ($UserAgentString in $UserAgent) { $HttpClient.DefaultRequestHeaders.Remove('User-Agent') | Out-Null if ($UserAgentString) { Write-Verbose "Using UserAgent '$UserAgentString'" $HttpClient.DefaultRequestHeaders.Add('User-Agent', $UserAgentString) } # This sends a GET request but only retrieves the headers $ResponseHeader = $HttpClient.GetAsync($URL, [System.Net.Http.HttpCompletionOption]::ResponseHeadersRead).Result # Exit the foreach if success if ($ResponseHeader.IsSuccessStatusCode) { break } } if ($ResponseHeader.IsSuccessStatusCode) { Write-Verbose 'Successfully retrieved headers' if ($ResponseHeader.RequestMessage.RequestUri.AbsoluteUri -ne $URL) { Write-Verbose "URL '$URL' redirects to '$($ResponseHeader.RequestMessage.RequestUri.AbsoluteUri)'" } try { $FileSize = $null $FileSize = [int]$ResponseHeader.Content.Headers.GetValues('Content-Length')[0] $FileSizeReadable = switch ($FileSize) { { $_ -gt 1TB } { '{0:n2} TB' -f ($_ / 1TB); Break } { $_ -gt 1GB } { '{0:n2} GB' -f ($_ / 1GB); Break } { $_ -gt 1MB } { '{0:n2} MB' -f ($_ / 1MB); Break } { $_ -gt 1KB } { '{0:n2} KB' -f ($_ / 1KB); Break } default { '{0} B' -f $_ } } Write-Verbose "File size: $FileSize bytes ($FileSizeReadable)" } catch { Write-Verbose 'Unable to determine file size' } # Try to get the last modified date from the "Last-Modified" header, use error handling in case string is in invalid format try { $LastModified = $null $LastModified = [DateTime]::ParseExact($ResponseHeader.Content.Headers.GetValues('Last-Modified')[0], 'r', [System.Globalization.CultureInfo]::InvariantCulture) Write-Verbose "Last modified: $($LastModified.ToString())" } catch { Write-Verbose 'Last-Modified header not found' } if ($FileName) { $FileName = $FileName.Trim() Write-Verbose "Will use supplied filename '$FileName'" } else { # Get the file name from the "Content-Disposition" header if available try { $ContentDispositionHeader = $null $ContentDispositionHeader = $ResponseHeader.Content.Headers.GetValues('Content-Disposition')[0] Write-Verbose "Content-Disposition header found: $ContentDispositionHeader" } catch { Write-Verbose 'Content-Disposition header not found' } if ($ContentDispositionHeader) { $ContentDispositionRegEx = @' ^.*filename\*?\s*=\s*"?(?:UTF-8|iso-8859-1)?(?:'[^']*?')?([^";]+) '@ if ($ContentDispositionHeader -match $ContentDispositionRegEx) { # GetFileName ensures we are not getting a full path with slashes. UrlDecode will convert characters like %20 back to spaces. $FileName = [System.IO.Path]::GetFileName([System.Web.HttpUtility]::UrlDecode($matches[1])) # If any further invalid filename characters are found, convert them to spaces. [IO.Path]::GetinvalidFileNameChars() | ForEach-Object { $FileName = $FileName.Replace($_, ' ') } $FileName = $FileName.Trim() Write-Verbose "Extracted filename '$FileName' from Content-Disposition header" } else { Write-Verbose 'Failed to extract filename from Content-Disposition header' } } if ([string]::IsNullOrEmpty($FileName)) { # If failed to parse Content-Disposition header or if it's not available, extract the file name from the absolute URL to capture any redirections. # GetFileName ensures we are not getting a full path with slashes. UrlDecode will convert characters like %20 back to spaces. The URL is split with ? to ensure we can strip off any API parameters. $FileName = [System.IO.Path]::GetFileName([System.Web.HttpUtility]::UrlDecode($ResponseHeader.RequestMessage.RequestUri.AbsoluteUri.Split('?')[0])) [IO.Path]::GetinvalidFileNameChars() | ForEach-Object { $FileName = $FileName.Replace($_, ' ') } $FileName = $FileName.Trim() Write-Verbose "Extracted filename '$FileName' from absolute URL '$($ResponseHeader.RequestMessage.RequestUri.AbsoluteUri)'" } } } else { Write-Verbose 'Failed to retrieve headers' } if ([string]::IsNullOrEmpty($FileName)) { # If still no filename set, extract the file name from the original URL. # GetFileName ensures we are not getting a full path with slashes. UrlDecode will convert characters like %20 back to spaces. The URL is split with ? to ensure we can strip off any API parameters. $FileName = [System.IO.Path]::GetFileName([System.Web.HttpUtility]::UrlDecode($URL.Split('?')[0])) [System.IO.Path]::GetInvalidFileNameChars() | ForEach-Object { $FileName = $FileName.Replace($_, ' ') } $FileName = $FileName.Trim() Write-Verbose "Extracted filename '$FileName' from original URL '$URL'" } $DestinationFilePath = Join-Path $Destination $FileName # Exit if -NoClobber specified and file exists. if ($NoClobber -and (Test-Path -LiteralPath $DestinationFilePath -PathType Leaf)) { Write-Error 'NoClobber switch specified and file already exists' return } # Open the HTTP stream $ResponseStream = $HttpClient.GetStreamAsync($URL).Result if ($ResponseStream.CanRead) { # Check TempPath exists and create it if not if (-not (Test-Path -LiteralPath $TempPath -PathType Container)) { Write-Verbose "Temp folder '$TempPath' does not exist" try { New-Item -Path $Destination -ItemType Directory -Force | Out-Null Write-Verbose "Created temp folder '$TempPath'" } catch { Write-Error "Unable to create temp folder '$TempPath': $_" return } } # Generate temp file name $TempFileName = (New-Guid).ToString('N') + ".tmp" $TempFilePath = Join-Path $TempPath $TempFileName # Check Destiation exists and create it if not if (-not (Test-Path -LiteralPath $Destination -PathType Container)) { Write-Verbose "Output folder '$Destination' does not exist" try { New-Item -Path $Destination -ItemType Directory -Force | Out-Null Write-Verbose "Created output folder '$Destination'" } catch { Write-Error "Unable to create output folder '$Destination': $_" return } } # Open file stream try { $FileStream = [System.IO.File]::Create($TempFilePath) } catch { Write-Error "Unable to create file '$TempFilePath': $_" return } if ($FileStream.CanWrite) { Write-Verbose "Downloading to temp file '$TempFilePath'..." $Buffer = New-Object byte[] 16KB $BytesDownloaded = 0 $ProgressTimer = Get-Date $ProgressIntervalMs = 250 while ($true) { try { # Read stream into buffer $ReadBytes = $ResponseStream.Read($Buffer, 0, $Buffer.Length) # Track bytes downloaded for progress bar $BytesDownloaded += $ReadBytes if (!$NoProgress -and (Get-Date) -gt $ProgressTimer.AddMilliseconds($ProgressIntervalMs)) { Write-Progress -Activity 'Downloading File' -Status $FileName -PercentComplete ($BytesDownloaded / $FileSize * 100) $ProgressTimer = Get-Date } # If end of stream if ($ReadBytes -eq 0) { $FileStream.Close() $FileStream.Dispose() try { Write-Verbose "Moving temp file to destination '$DestinationFilePath'" $DownloadedFile = Move-Item -LiteralPath $TempFilePath -Destination $DestinationFilePath -Force -PassThru } catch { Write-Error "Error moving file from '$TempFilePath' to '$DestinationFilePath': $_" return } if ($IsWindows) { if ($BlockFile) { Write-Verbose 'Marking file as downloaded from the internet' Set-Content -LiteralPath $DownloadedFile -Stream 'Zone.Identifier' -Value "[ZoneTransfer]`nZoneId=3" } else { Unblock-File -LiteralPath $DownloadedFile } } if ($LastModified -and -not $IgnoreDate) { Write-Verbose 'Setting Last Modified date' $DownloadedFile.LastWriteTime = $LastModified } Write-Verbose 'Download complete!' if ($PassThru) { $DownloadedFile } break } $FileStream.Write($Buffer, 0, $ReadBytes) } catch { Write-Error "Error downloading file: $_" $FileStream.Close() $FileStream.Dispose() break } } } } else { Write-Error 'Failed to start download' } # Reset this to avoid reusing the same name when fed multiple URLs via the pipeline $FileName = $null } end { $HttpClient.Dispose() } } |