Nowaday I am working on automated posts to Twitter and Facebook.
Implementation a plugin for twitter is very easily. Twitter provides special authentication keys for not interactive authentication for your self. With these keys you can post tweet as yourself.
However facebook needs interactive login, hence plugin development is very very difficult. After some searches I can generate an access token which may not expire (if facebook do not force to expire it). Then I write a simple http post code to publish my blog posts.
For twitter you can use the gem twitter. Its documentation is very clear. I used it. However I didn’t find an easy gem for facebook. I tried koala, minifb, omniauth and rest-graph. The rest-graph can provide what I want, however I didn’t use it and write a simple uri post code.