Private/Get-Link.ps1
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function Get-Link { <# .SYNOPSIS Returns a specific link from a web page. .DESCRIPTION Returns a specific link from a web page. .NOTES Site: https://packageology.com Author: Dan Gough Twitter: @packageologist .LINK https://github.com/DanGough/Nevergreen .PARAMETER Uri The URI to query. .PARAMETER MatchProperty Which property the RegEx pattern should be applied to, e.g. href, outerHTML, class, title. .PARAMETER Pattern The RegEx pattern to apply to the selected property. Supply an array of patterns to receive multiple links. .PARAMETER ReturnProperty Optional. Specifies which property to return from the link. Defaults to href, but 'data-filename' can also be useful to retrieve. .PARAMETER UserAgent Optional parameter to provide a user agent for Invoke-WebRequest to use. Examples are: Googlebot: 'Googlebot/2.1 (+http://www.google.com/bot.html)' Microsoft Edge: 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/42.0.2311.135 Safari/537.36 Edge/12.246' .EXAMPLE Get-Link -Uri 'http://somewhere.com' -MatchProperty href -Pattern '\.exe$' Description: Returns first download link matching *.exe from http://somewhere.com. #> [CmdletBinding(SupportsShouldProcess = $False)] param ( [Parameter( Mandatory = $true, Position = 0, ValueFromPipeline)] [ValidatePattern('^(http|https)://')] [Alias('Url')] [String] $Uri, [Parameter( Mandatory = $true, Position = 1)] [ValidateNotNullOrEmpty()] #[ValidateSet('href', 'outerHTML', 'innerHTML', 'outerText', 'innerText', 'class', 'title', 'tagName', 'data-filename')] [String] $MatchProperty, [Parameter( Mandatory = $true, Position = 2)] [ValidateNotNullOrEmpty()] [String[]] $Pattern, [Parameter( Mandatory = $false, Position = 3)] [ValidateNotNullOrEmpty()] [String] $ReturnProperty = 'href', [Parameter( Mandatory = $false)] [String] $UserAgent, [System.Collections.Hashtable] $Headers, [Switch] $PrefixDomain, [Switch] $PrefixParent ) $ProgressPreference = 'SilentlyContinue' $ParamHash = @{ Uri = $Uri Method = 'GET' UseBasicParsing = $True DisableKeepAlive = $True ErrorAction = 'Stop' } if ($UserAgent) { $ParamHash.UserAgent = $UserAgent } if ($Headers) { $ParamHash.Headers = $Headers } try { $Response = Invoke-WebRequest @ParamHash foreach ($CurrentPattern in $Pattern) { $Link = $Response.Links | Where-Object $MatchProperty -Match $CurrentPattern | Select-Object -First 1 -ExpandProperty $ReturnProperty if ($PrefixDomain) { $BaseURL = ($Uri -split '/' | Select-Object -First 3) -join '/' $Link = Set-UriPrefix -Uri $Link -Prefix $BaseURL } elseif ($PrefixParent) { $BaseURL = ($Uri -split '/' | Select-Object -SkipLast 1) -join '/' $Link = Set-UriPrefix -Uri $Link -Prefix $BaseURL } $Link } } catch { Write-Error "$($MyInvocation.MyCommand): $($_.Exception.Message)" } } |