Rails - extract seo keywords from block of text

I need to generate seo meta keyword tags based upon user generated wiki content.

Say I have a开发者_如何转开发n article and a predefined list of keywords/phrases, is there some good method to grab matched article keywords? Keywords may not be of one word length and will be given a predefined weight as to which keywords are used first. Some implementation of Nokogiri seems the obvious choice but I wondered if there were something more complete for this exact scenario.

You could process your text thanks to a semantic API, it will give you a list of potential keywords + the score associated.

I've begun to develop this gem: https://github.com/apneadiving/SemExtractor

It still needs some improvements for error handling but it's fully operational to query the following engines:

• Zemanta
• Semantic Hacker from Textwise
• Yahoo Boss
• OpenCalais

If you're only wanting to grab keywords for the meta keyword tag, that's not really worth your time. Google doesn't pay attention to those anymore.

Here's a good post about it, with a video of Matt Cutts from Google explaining that the meta keyword tag doesn't play a part in search engine rankings. http://www.stepforth.com/blog/2010/meta-keyword-tag-dead-seo/

What is worth your time? Good title tags.