Private/Invoke-PatFileDownload.ps1
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function Invoke-PatFileDownload { <# .SYNOPSIS Downloads a file from a Plex server. .DESCRIPTION Internal helper function that downloads binary files (media, subtitles) from a Plex server with progress reporting. Handles large files and supports resuming interrupted downloads. .PARAMETER Uri The complete URI to download from, including authentication token. .PARAMETER OutFile The destination file path. .PARAMETER ExpectedSize Optional expected file size in bytes. Used for progress calculation and resume detection. .PARAMETER Resume When specified, attempts to resume a partial download if the destination file already exists and is smaller than expected. .OUTPUTS System.IO.FileInfo Returns the downloaded file information. .EXAMPLE Invoke-PatFileDownload -Uri "http://plex:32400/library/parts/123?download=1&X-Plex-Token=abc" -OutFile "C:\movie.mkv" Downloads the file to the specified path. .EXAMPLE Invoke-PatFileDownload -Uri $uri -OutFile $path -ExpectedSize 4000000000 -Resume Attempts to resume a partial download. #> [CmdletBinding()] [OutputType([System.IO.FileInfo])] param ( [Parameter(Mandatory = $true)] [ValidateNotNullOrEmpty()] [string] $Uri, [Parameter(Mandatory = $true)] [ValidateNotNullOrEmpty()] [string] $OutFile, [Parameter(Mandatory = $false)] [long] $ExpectedSize = 0, [Parameter(Mandatory = $false)] [switch] $Resume ) # Ensure destination directory exists $destinationDir = Split-Path -Path $OutFile -Parent if ($destinationDir -and -not (Test-Path -Path $destinationDir)) { Write-Verbose "Creating destination directory: $destinationDir" New-Item -Path $destinationDir -ItemType Directory -Force | Out-Null } # Check for existing partial download $existingSize = 0 $headers = @{} if ($Resume -and (Test-Path -Path $OutFile)) { $existingFile = Get-Item -Path $OutFile $existingSize = $existingFile.Length # If we have expected size and existing file matches, skip download if ($ExpectedSize -gt 0 -and $existingSize -eq $ExpectedSize) { Write-Verbose "File already exists with correct size, skipping download" return $existingFile } # If existing file is smaller than expected, attempt resume if ($ExpectedSize -gt 0 -and $existingSize -lt $ExpectedSize) { Write-Verbose "Resuming download from byte $existingSize" $headers['Range'] = "bytes=$existingSize-" } elseif ($existingSize -gt 0) { # Existing file is larger or we don't know expected size - start fresh Write-Verbose "Existing file size mismatch, starting fresh download" Remove-Item -Path $OutFile -Force $existingSize = 0 } } elseif (Test-Path -Path $OutFile) { # Not resuming, remove existing file Remove-Item -Path $OutFile -Force } try { Write-Verbose "Downloading file from: $Uri" Write-Verbose "Destination: $OutFile" $webRequestParams = @{ Uri = $Uri Headers = $headers UseBasicParsing = $true ErrorAction = 'Stop' } # For resume, we need to handle the response differently if ($existingSize -gt 0 -and $headers.ContainsKey('Range')) { # Resuming - append to existing file $response = Invoke-WebRequest @webRequestParams # Check if server supports range requests (206 Partial Content) if ($response.StatusCode -eq 206) { # Append to existing file $fileStream = [System.IO.FileStream]::new($OutFile, [System.IO.FileMode]::Append) try { $fileStream.Write($response.Content, 0, $response.Content.Length) } finally { $fileStream.Close() } Write-Verbose "Appended $($response.Content.Length) bytes to existing file" } else { # Server doesn't support range requests, save full response Write-Verbose "Server does not support resume, downloading full file" [System.IO.File]::WriteAllBytes($OutFile, $response.Content) } } else { # Fresh download - use -OutFile for efficient streaming Invoke-WebRequest @webRequestParams -OutFile $OutFile } # Verify download if (-not (Test-Path -Path $OutFile)) { throw "Download completed but file not found at: $OutFile" } $downloadedFile = Get-Item -Path $OutFile # Verify size if expected size was provided if ($ExpectedSize -gt 0 -and $downloadedFile.Length -ne $ExpectedSize) { Write-Warning "Downloaded file size ($($downloadedFile.Length)) does not match expected size ($ExpectedSize)" } Write-Verbose "Download completed: $($downloadedFile.Length) bytes" return $downloadedFile } catch { # Clean up partial download on error (unless resuming) if (-not $Resume -and (Test-Path -Path $OutFile)) { Remove-Item -Path $OutFile -Force -ErrorAction SilentlyContinue } throw "Failed to download file: $($_.Exception.Message)" } } |