Module: MiniFB

Defined in:
lib/photo_mini_fb.rb

Defined Under Namespace

Classes: FaceBookError, FaceBookSecret, Photos, Session, User

Constant Summary collapse

FB_URL =

Global constants

"http://api.facebook.com/restserver.php"
FB_API_VERSION = 
"1.0"
BAD_JSON_METHODS = 
["users.getloggedinuser", "auth.promotesession", "users.hasapppermission", "Auth.revokeExtendedPermission", "pages.isAdmin"].collect { |x| x.downcase }
@@logging = 
false

Class 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/photo_mini_fb.rb', line 138

def MiniFB.call( api_key, secret, method, 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

    if method == "photos.upload"
      filename = kwargs.fetch("filename")
      kwargs.delete("filename")
    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
    # todo: convert symbols to strings, symbols break the next line
    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
    begin
      if method == "photos.upload"
        response = MiniFB.post_upload(filename, kwargs)
      else
        response = Net::HTTP.post_form( URI.parse(FB_URL), kwargs )
      end
    rescue SocketError => err
        raise IOError.new( "Cannot connect to the facebook server: " + err )
    end

    # Handle response
    return response.body if custom_format

    fb_method = kwargs["method"].downcase
    body = response.body

    puts 'response=' + body.inspect if @@logging
    begin
        data = JSON.parse( body )
        if data.include?( "error_msg" ) then
            raise FaceBookError.new( data["error_code"] || 1, data["error_msg"] )
        end

    rescue JSON::ParserError => ex
        if BAD_JSON_METHODS.include?(fb_method) # Little hack because this response isn't valid JSON
            if body == "0" || body == "false"
                return false
            end
            return body
        else
            raise ex
        end
    end
    return data
end

.disable_logging ⇒ Object 



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# File 'lib/photo_mini_fb.rb', line 20

def self.disable_logging
    @@logging = false
end

.enable_logging ⇒ Object 



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# File 'lib/photo_mini_fb.rb', line 16

def self.enable_logging
    @@logging = true
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/photo_mini_fb.rb', line 264

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

.post_upload(filename, kwargs) ⇒ Object 



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# File 'lib/photo_mini_fb.rb', line 208

def MiniFB.post_upload(filename, kwargs)
  content = open(filename, 'rb') { |f| f.read }
  boundary = Digest::MD5.hexdigest(content)
  header = {'Content-type' => "multipart/form-data, boundary=#{boundary}"}

  # Build query
  query = ''
  kwargs.each { |a, v|
    query <<
      "--#{boundary}\r\n" <<
      "Content-Disposition: form-data; name=\"#{a}\"\r\n\r\n" <<
      "#{v}\r\n"
  }
  query <<
    "--#{boundary}\r\n" <<
    "Content-Disposition: form-data; filename=\"#{File.basename(filename)}\"\r\n" <<
    "Content-Transfer-Encoding: binary\r\n" <<
    "Content-Type: image/jpeg\r\n\r\n" <<
    content <<
    "\r\n" <<
    "--#{boundary}--"

  # Call Facebook with POST multipart/form-data request
  uri = URI.parse(FB_URL)
  Net::HTTP.start(uri.host) {|http| http.post uri.path, query, header}
end

.validate(secret, arguments) ⇒ Object

DEPRECATED, use verify_signature instead



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# File 'lib/photo_mini_fb.rb', line 289

def MiniFB.validate( secret, arguments )

    signature = arguments.delete( "fb_sig" )
    return arguments 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
        unsigned # Hash is incorrect, return only unsigned fields.
    else
        unsigned.merge signed
    end
end

.verify_signature(secret, arguments) ⇒ Object

Returns true is signature is valid, false otherwise.



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# File 'lib/photo_mini_fb.rb', line 236

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