Web pages should specify their canonical URL (permalink)
Posted by Chris Roos Fri, 14 Dec 2007 17:49:00
I’ve been using del.icio.us to record items on ebay that I’m interested in. The problem is that each ebay page can have multiple URLs – none of which redirect to the canonical version. I can end up tagging the same listing twice if I happen to visit it with two different URLs – this is annoying. It wouldn’t be hard for them to either redirect to the canonical version or just add a <link rel="bookmark" ... /> tag to the document. This way, I could ensure that I was always bookmarking the same version (even modifying the del.icio.us plugin if necessary).
This isn’t just a problem for ebay: lots of sites duplicate their content on multiple URLs (hello retailers). Maybe in the short term we could come up with some rules for turning any given URL on a specific site into its canonical representation. That sounds like a nice, useful, little service to me. Can someone build it for me please?
Matt B said on Sun, 16 Dec 2007 15:53:28:
With ebay… I think you are better off just giving up… unless you bookmarked the auction ID and stripped of the other parameters. Each auction has a unique number that can be tracked. You seem to have a grasp of JavaScript so maybe you could build a linklet?
Chris said on Mon, 17 Dec 2007 13:37:22:
Hey Matt,
I’ve started to wonder whether a greasemonkey script might do what I need. The script would just recognise the page you’re on and look up, in a set of rules, how to find the canonical URL. Sadly, I’m not sure when I might find time to do it.