URLs aren’t always (directly) pointing to a resource. Often, URL act as shortcuts or static addresses that always point to latest versions. PowerShell can reveal the true URL of a resource, and you can use this for a number of cases.
Here’s an example how to resolve a shortcut link:
# this is the URL we got: $URLRaw = 'http://go.microsoft.com/fwlink/?LinkID=135173' # we do not allow automatic redirection and instead read the information # returned by the webserver ourselves: $page = Invoke-WebRequest -Uri $URLRaw -UseBasicParsing -MaximumRedirection 0 -ErrorAction Ignore $target = $page.Headers.Location "$URLRaw -> $target"
And here is an example on how to resolve a product version from a static link. The latest PowerShell version can always be found using this static URL:
https://github.com/PowerShell/PowerShell/releases/latest
If you’d like to know the actual version of the latest release, try and resolve the URL:
$URLRaw = 'https://github.com/PowerShell/PowerShell/releases/latest' # we do not allow automatic redirection and instead read the information # returned by the webserver ourselves: $page = Invoke-WebRequest -Uri $URLRaw -UseBasicParsing -MaximumRedirection 0 -ErrorAction Ignore $realURL = $page.Headers.Location $version = Split-Path -Path $realURL -Leaf "PowerShell 7 latest version: $version"
The same approach works for PowerShell Gallery modules as well:
# name of a module published at powershellgallery.com $ModuleName = 'ImportExcel' $URL = "https://www.powershellgallery.com/packages/$ModuleName" # get full URL (including latest version): $page = Invoke-WebRequest -Uri $URL -UseBasicParsing -MaximumRedirection 0 -ErrorAction Ignore $realURL = $page.Headers.Location # return version only: $latest = Split-Path -Path $realURL -Leaf "Module $ModuleName latest version: $latest"
