Getting a Document or TreeNode from a URL in Kentico

I was creating a web service method that was called via AJAX from an existing page. I needed to get the Document from which the service was being called but I didn’t want to dump the DocumentID/NodeID to the page. This is how my request was made:

$.post('/Path/To/Service.aspx'
    , {
        documenturl: document.location.href
    });

Within the service I had the document URL of the calling page, but I needed more information about that Document. Using the PageInfoProvider I was able to translate the URL into a PageInfo object:

var pageInfo = PageInfoProvider.GetPageInfoForUrl(url, "en-US", (string)null, true, true, SiteInfoProvider.CurrentSiteName);

From there you can get the full Document/TreeNode given the ID’s on the PageInfo object:

pageInfo.DocumentID
            
pageInfo.NodeID

I was able to find this information by reflecting CMS.URLRewritingEngine.dll and examining the URLRewriter class and the RewriteUrl method.