Google Reader API - How do you share by article url as oppose to item id?

I've done a decent amount of research on the unofficial reader api and sifted through other questions, but none of them quite have what I want. How to开发者_如何学编程 share an article if you know the article id is well documented, but I want to know how to share an article if you don't know the id (i.e. how to transform url -> id or how to share directly using the url as a parameter).

I imagine it is possible, because the functionality pretty much mimics the behavior of the awesome "Note in Reader" bookmarklet they have.

Thanks!

The "Note in Reader" bookmarklet ends up sending a POST to http://www.google.com/reader/api/0/item/edit with these parameters:

• client: your client ID
• T: action token
• url: item url
• title: title (interpreted as plain text)
• snippet: body (interpreted as HTML)
• share: true or false
• tags: additional tag to apply to the created note, e.g. user/-/label/foo (optional, repeat the parameter if you wish to add mutliple tags)
• srcUrl: URL of the source site
• srcTitle: title of the source site