Module: MiniFB

Defined in:
lib/mini_fb.rb

Defined Under Namespace

Classes: BadJSONDataError, FaceBookError, FaceBookSecret, Photos, Session, User

Constant Summary collapse

FB_URL = 
"http://api.facebook.com/restserver.php"
FB_API_VERSION = 
"1.0"
RETRY_ATTEMPTS = 
10
BAD_JSON_METHODS = 
%w{ users.getLoggedInUser }
@@logging = 
false

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.call(api_key, secret, method, kwargs) ⇒ Object

The secret argument should be an instance of FacebookSecret to hide value from simple introspection.



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# File 'lib/mini_fb.rb', line 140

def MiniFB.call( api_key, secret, method, kwargs )

    kwargs = Hashie::Mash.new kwargs

    puts 'kwargs=' + kwargs.inspect if @@logging

    if secret.is_a? String
        secret = FaceBookSecret.new(secret)
    end

    # Prepare arguments for call
    call_id = kwargs.fetch("call_id", true)
    if call_id == true then
        kwargs["call_id"] = Time.now.tv_sec.to_s
    else
        kwargs.delete("call_id")
    end

    custom_format = kwargs.include?("format") or kwargs.include?("callback")
    kwargs["format"] ||= "JSON"
    kwargs["v"] ||= FB_API_VERSION
    kwargs["api_key"]||= api_key
    kwargs["method"] ||= method

    # Hash with secret
    arg_string = String.new
    kwargs.sort.each { |kv| arg_string << kv[0] << "=" << kv[1].to_s }
    kwargs["sig"] = Digest::MD5.hexdigest( arg_string + secret.value.call )

    # Call website with POST request
    attempt = 0
    begin
      response = Net::HTTP.post_form( URI.parse(FB_URL), kwargs )
    rescue SocketError, Errno::ECONNRESET, EOFError => err
      if attempt < RETRY_ATTEMPTS
        attempt += 1
        retry
      else
        raise
      end
      # raise IOError.new( "Cannot connect to the facebook server: " + err )
    rescue
      raise
    end
    
    # Handle response
    
    body = response.body
    return body if custom_format
    unescaped_attempt = false

    begin
      data = JSON.parse body
      
      data.collect! {|datum| Hashie::Mash.new datum } if data.is_a?(Array) && data.length > 0 && data[0].is_a?(Hash)
      
      puts 'response=' + data.inspect if @@logging
      if data.include?( "error_msg" ) then
          raise FaceBookError.new( data["error_code"] || 1, data["error_msg"] )
      end
    rescue JSON::ParserError => ex
      return body if BAD_JSON_METHODS.include? kwargs["method"]
      return (body == 'true') if %w{true false}.include?(body) # Hack for Facebook boolean API calls with BAD JSON.
      
      unescaped_body = body[/\A"(.*)"\z/m,1]
      if unescaped_body && !unescaped_attempt
        unescaped_attempt = true
        body = unescaped_body.gsub('\\', '')
        retry
      end
      
      raise BadJSONDataError, "#{kwargs["method"]} returned \"#{body}\""
    end
    
    data.is_a?(Hash) ? Hashie::Mash.new(data) : data
end

.login_url(api_key, options = {}) ⇒ Object

Returns the login/add app url for your application.

options:

- :next => a relative next page to go to. relative to your facebook connect url or if :canvas is true, then relative to facebook app url
- :canvas => true/false - to say whether this is a canvas app or not



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# File 'lib/mini_fb.rb', line 246

def self.(api_key, options={})
   = "http://api.facebook.com/login.php?api_key=#{api_key}"
   << "&next=#{defined?(Rack) ? Rack::Utils.escape(Rack::Utils.unescape(options[:next])) : CGI.escape(CGI.unescape(options[:next])) if options[:next]}" if options[:next]
   << "&canvas" if options[:canvas]
  
end

.verify_signature(secret, arguments) ⇒ Object

Returns true is signature is valid, false otherwise.



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# File 'lib/mini_fb.rb', line 218

def MiniFB.verify_signature( secret, arguments )
    signature = arguments.delete( "fb_sig" )
    return false if signature.nil?

    unsigned = Hash.new
    signed = Hash.new

    arguments.each do |k, v|
        if k =~ /^fb_sig_(.*)/ then
            signed[$1] = v
        else
            unsigned[k] = v
        end
    end

    arg_string = String.new
    signed.sort.each { |kv| arg_string << kv[0] << "=" << kv[1] }
    if Digest::MD5.hexdigest( arg_string + secret ) == signature
        return true
    end
    return false
end

Instance Method Details

#disable_logging ⇒ Object 



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# File 'lib/mini_fb.rb', line 22

def disable_logging
    @@logging = false
end

#enable_logging ⇒ Object 



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# File 'lib/mini_fb.rb', line 18

def enable_logging
    @@logging = true
end