Get data of a post using ID provided by facebook realtime-api

Question

I am using Facebook realtime api, as I get only the updates and have to fetch the whole data by hitting the server again. I have a page, my app added to that hence I am getting page feed(like, comment, post, all). When any user posts on the page, we get the update from Facebook realtime update api. But when I try to fetch post data using the Koala gem it gives me error, note that error is not in case of Update from Page itself(page admin) but when some other user posts on it. Following is the code for help :-

Trying to fetch using long lived page-token, and without that too, failing both ways

@@graph = Koala::Facebook::API.new ACCESS_TOKENS["facebook"]["page_token"]

@@public_graph = Koala::Facebook::API.new

JSON response from facebook :-

{"object"=>"page",
   "entry"=>
    [{"id"=>"123412341234234",
      "time"=>1412341234,
      "changes"=>
       [{"field"=>"feed",
         "value"=>
          {"item"=>"post",
           "verb"=>"add",
           "post_id"=>123412341234123,
           "sender_id"=>1234123412}}]}]}}

@@public_graph.get_object("123412341234123")
*** Koala::Facebook::ClientError Exception: type: GraphMethodException, code: 100, message: Unsupported get request. [HTTP 400]

@@graph.get_object("123412341234123")
*** Koala::Facebook::ClientError Exception: type: GraphMethodException, code: 100, message: Unsupported get request. [HTTP 400]

Please help me out to understand how to fetch the public post data using the post_id provided by the realtime-updates api of facebook.

Answer 1

Q: how to fetch the public post data using the post_id provided by the realtime-updates api of facebook.

For fetching public data of the post from the page, you will need to specify both the IDs (page id as well as post id) you are getting in the RT hit form fb.

You will need to pass id as <page_id>_<post_id>. In your case, it will be:

rt_hit = {"object"=>"page",
       "entry"=>
        [{"id"=>"123412341234234",
          "time"=>1412341234,
          "changes"=>
           [{"field"=>"feed",
             "value"=>
              {"item"=>"post",
               "verb"=>"add",
               "post_id"=>123412341234123,
               "sender_id"=>1234123412}}]}]}}

entry     = rt_hit["entry"].first // you may want to have loop instead of `first`
public_id = "#{entry['id']}_#{entry['changes'].first['value']['post_id']}"

@@public_graph.get_object(public_id) // fetch object