How to get value of a link from a website with powershell?-CodePudding

I want to get download URL of the last version of GIMP from it's site ,I wrote a script but it returns the link name I do not know how to get the value

$web = Invoke-WebRequest -Uri "https://download.gimp.org/pub/gimp/v2.10/windows/"
$web.Links | Where-Object href -like '*exe' | select -Last 1 | select -expand href

the above code returne link name (gimp-2.10.32-setup.exe) but I need the value ("https://download.gimp.org/pub/gimp/v2.10/windows/gimp-2.10.32-setup.exe") can someone guide me how to do it

CodePudding user response：

You know that the url presented is relative. Just append the root part of the URL yourself.

  $Uri = 'https://download.gimp.org/pub/gimp/v2.10/windows/'
  $web = Invoke-WebRequest -Uri $uri
  $ExeRelLink =  $web.Links | Where-Object href -like '*exe' | select -Last 1 -expand href 
# Here is your download link.
$DownloadLink = $Uri   $ExeRelLink

Additional Note

You can combine the -Last and -Expand from your 2 select statements into 1.

CodePudding user response：

There are several downloads sites with exactly the same or very similar layout to this GIMP page, including many Apache projects like Tomcat and ActiveMQ. I had written a little function to parse these and other pages in the past, and interestingly it also worked for this GIMP page. I thought it was worth sharing as such.

Function Extract-FilenameFromWebsite {
    [cmdletbinding()]
    Param(
        [parameter(Position=0,ValueFromPipeline)]
        $Url
    )

    begin{
        $pattern = '<a href. ">(?<FileName>. ?\.. ?)</a>\s (?<Date>\d -. ?)\s{2,}(?<Size>\d \w)?'
    }

    process{
        $website = Invoke-WebRequest $Url -UseBasicParsing

        switch -Regex ($website.Content -split '\r?\n'){
            $pattern {
                [PSCustomObject]@{
                    FileName     = $matches.FileName
                    URL          = '{0}{1}' -f $Url,$matches.FileName
                    LastModified = [datetime]$matches.Date
                    Size         = $matches.Size
                }
            }
        }
    }
}

It's assumed the site passed in has a trailing slash. If you want to account for either, you can add this simple line to the process block.

if($Url -notmatch '/$'){$Url = "$Url/"}

To get the latest version, call the function like this

$url = 'https://download.gimp.org/pub/gimp/v2.10/windows/'

$latest = Extract-FilenameFromWebsite -Url $Url | Where-Object filename -like '*exe' |
    Sort-Object LastModified | Select-Object -Last 1

$latest.url

Or you could expand the property while retrieving

$url = 'https://download.gimp.org/pub/gimp/v2.10/windows/'

$latesturl = Extract-FilenameFromWebsite -Url $Url | Where-Object filename -like '*exe' |
    Sort-Object LastModified | Select-Object -Last 1 -ExpandProperty URL

$latesturl