Question

I am developing a Facebook Application and I want to present information to users if their friends are also using the application.

I found I way to get the user’s friends that are using the application in the following format:

[
 {
  "uid":1234,
  "name":"Friend Name1",
  "is_app_user":true
 },
 {
  "uid":12345,
  "name":"Friend Name 2",
  "is_app_user":true
 }
]

I only need an array with the UIDs to query my user database. Can someone provide an efficient example on how to prepare the above JSON Object?

I want to be able to use:

User.find_all_by_uid( uids )

Thanks

Answer 1

This should get you on your way.

do:

gem install json

Check: http://flori.github.com/json/ for details

Here is the example you requested that gives you array of ids:

require 'rubygems'
require 'json'

def parse

   data = '[{"uid":1234,"name":"Friend Name1","is_app_user":true},{"uid":12345,"name":"Friend Name 2","is_app_user":true}]'
   result = JSON.parse(data)

   uids = []
   result.each do |result|
      result.each do|key ,value|
        uids .push(value) if key == "uid"
     end
   end

   puts uids 

end

parse

Hope that helps!