PowerShell v3 Cmdlet: Get-CourseraVideos

function Get-CourseraVideos<br>{<br><#<br>.SYNOPSIS<br><br>    Downloads all the videos from a Coursera class preview site.<br><br>.DESCRIPTION<br><br>    The Get-CourseraVideos cmdlet scrapes the video content from a class 'preview' site.<br><br>    If you have a Coursera account, do keep in mind that this tool is potentially in violation of the Coursera Terms of Service (Effective as of 10 April, 2012).<br><br>.PARAMETER PreviewURL<br><br>    Specifies the URL of the Coursera 'preview' site.<br><br>.PARAMETER Path<br><br>    Specifies the path to which videos will be downloaded.<br><br>.EXAMPLE<br><br>    C:\PS> Get-CourseraVideos -PreviewURL 'https://class.coursera.org/compilers-2012-selfservice/lecture/preview' -Path 'C:\Videos\Compilers'<br><br>.LINK<br>http://www.exploit-monday.com/2012/08/Get-CourseraVideos.html<br><br>.LINK<br>https://www.coursera.org/about/terms<br>#><br><br>    [CmdletBinding()] Param (<br>        [Parameter( Mandatory = $True,<br>                    Position = 0 )]<br>        [ValidateNotNullOrEmpty()]<br>        [String]<br>        $PreviewURL,<br><br>        [Parameter( Position = 1 )]<br>        [ValidateNotNullOrEmpty()]<br>        [String]<br>        $Path = ($pwd) # Download to current working directory by default<br>    )<br><br>    Set-StrictMode -Version 3<br><br>    # Throw error if the path does not exist<br>    if (!(Test-Path $Path))<br>    {<br>        Throw [System.Management.Automation.ItemNotFoundException] "Cannot find path '$Path' because it does not exist."<br>    }<br><br>    $SiteContent = Invoke-WebRequest $PreviewURL -ErrorVariable WebError<br><br>    if ($WebError) { Return }<br><br>    $FileSafeChar = [Char] ''<br><br>    $FileIndex = 1<br><br>    $Lectures = $SiteContent.Links | Where-Object { $_.class -eq 'lecture-link' } 2> $null<br><br>    if ($Lectures -eq $null)<br>    {<br>        Throw "An invalid Coursera preview URL was provided."<br>    }<br>    else<br>    {<br>        $TotalVideos = $Lectures.Length<br><br>        $Lectures |<br>            ForEach-Object {<br>                # Get video title<br>                $Title = $_.innerText<br>                # If the title contains a bad filename character, replace it with ''<br>                foreach ($Char in [IO.Path]::GetInvalidFileNameChars()) { $Title = $Title.Replace($Char, $FileSafeChar) }<br>                # Prepend numerical index to the title<br>                $Title = "$($FileIndex.ToString('D2')) $($Title)"<br><br>                # Get video link<br>                $SiteContent = Invoke-WebRequest $_.href<br>                $VideoLink =  ($SiteContent.ParsedHtml.body.getElementsByTagName('SOURCE') |<br>                    Where-Object {$_.GetAttribute('type', 0) -eq 'video/mp4'}).GetAttribute('src', 0)<br><br>                $FilePath = Join-Path $Path "$($Title).mp4"<br><br>                Write-Progress -Activity 'Downloading Coursera Videos...' -PercentComplete ((($fileIndex - 1) / $TotalVideos) * 100)`<br>                    -CurrentOperation $VideoLink<br><br>                Write-Verbose "Downloading $VideoLink to $FilePath"<br><br>                # Download the video<br>                $WebClient = New-Object System.Net.WebClient<br>                $WebClient.DownloadFile($VideoLink, $FilePath)<br><br>                $FileIndex++<br>            }<br>    }<br>}