Post picture to wall on facebook

koal-facebook-post

to create Facebook events with a picture through the Graph API you need to use a multipart post request and give the image the key "picture". 
This is not documented. At all. Anywhere. Except here.

To do this in Koala, you can use a line like this:

    graph = Koala::Facebook::GraphAPI.new( oauth.get_app_access_token )
    graph.put_object( APP_ID, "events", {
      :name        => "Some event",
      :start_time  => Time.now.to_s,
      :description => "Facebook API docs suck",
      :picture     => Koala::UploadableIO.new("public/images/gamej_logo.png")
    })


The UploadableIO object causes the underlying Koala request method to use multipart POST - also undocumented - and use the correct key name.

For anyone else suffering with Koala, you may need to use the graph_call method, which takes the object ID you want to mess with, and the arguments you want to post - unlike the put_object method, which takes the parent object ID and the connection you want to post to.