Description

These are some helper methods to get you along in life. Use wisely, young one.

Public Instance methods

connect (host=nil)

Connect somewhere to Facebook! Will either make a new @http or try to change the Host header to portray where we were trying to go. 

  fb.connect 'emerson.facebook.com'

     # File facebook_bot/helper.rb, line 78
 78:   def connect host=nil 
 79:     #should we try to connect to our default_host? 

 80:     #changes on a network to network basis. 

 81:     #www if you're on a regional network. 

 82:     if host.nil? && @default_host 
 83:       host = @default_host 
 84:     elsif host.nil? 
 85:       host = 'www.facebook.com' 
 86:     end 
 87:     #if we havent connected yet, or we're trying to connect to upload. 

 88:     #upload requires its own connection, it wont accept the Host trick that's 

 89:     #happenin' below. 

 90:     if @http.nil? || host=='upload.facebook.com' 
 91:       host = 'www.facebook.com' unless host == 'upload.facebook.com' 
 92:       @http = Net::HTTP.new(host) 
 93:       puts "Created new connection to #{host}." 
 94:     #looks like for some reason we're not connected to www, and we're not 

 95:     #trying to upload, so we might as well reset to www and trick the Host. 

 96:     elsif @http.address != 'www.facebook.com' && host != 'upload.facebook.com'
 97:       @http = Net::HTTP.new('www.facebook.com') 
 98:       @opts[:headers]['Host'] = host 
 99:       puts "Reset connection to #{host}." 
100:     #just change the Host header. This is so we don't have to make unnecessary 

101:     #connections to northeastern.facebook.com, bu.facebook.com, etc. etc. 

102:     #www.facebook.com should be able to handle all of these connections. 

103:     #Hopefully. 

104:     elsif @opts[:headers]['Host'] != host 
105:       @opts[:headers]['Host'] = host 
106:       puts "Changed 'Host' to #{host}." 
107:     end 
108:   end

do_http () {|| ...}

All HTTP calls should be made through here, since this method checks whether the cookie is still valid. If it‘s not, it logs back in and tries again. Example: 

  req = do_http { @http.get2(url, @opts[:headers]) }

     # File facebook_bot/helper.rb, line 115
115:   def do_http 
116:     req = yield 
117:       if req.code.to_i == 302
118:         location = URI.parse(req.response['location']).path 
119:           if location == "" || location == "/" || location == "/login.php" 
120:             cookie_expired
121:             retry
122:           end
123:       elsif req.code.to_i == 200 && req.body.include?("Your session has timed out.")
124:         cookie_expired
125:         retry
126:       end
127:     req
128:   end

get_ids_from_url (url, ids)

Gets the contents of any IDs it finds on a given page. Takes an array of IDs. Returns a hash of ID information, keys being the IDs provided. Useful for getting basic information from a page, such as the verification post_form_id‘s, and any other information you so desire. Will try to extract this information from the ID, or give up: (in order) ID value, ID src, ID innerHTML. 

    id_info = fb.get_ids_from_url '/home.php', ['post_form_id']

    # File facebook_bot/helper.rb, line 23
23:   def get_ids_from_url url, ids
24:     elements = {}
25:     # go to the url

26:     doc = hpricot_get_url url
27:     
28:     ids.each do |id|
29:       tries = 0
30:       while elements[id].nil? 
31:         ele = doc.at("##{id}")
32:         if ele.nil?
33:           puts "cannot get id #{id}"
34:           elements[id] = 'unknown'
35:         elsif ele.attributes['value']
36:           elements[id] = ele.attributes['value']
37:         elsif ele.attributes['src']
38:           elements[id] = ele.attributes['src']
39:         elsif ele.inner_html
40:           elements[id] = ele.inner_html
41:         end
42:       end
43:     end
44:     elements
45:   end

hpricot_get_url (url)

Will get a URL and parse it with the (lovely) hpricot library. Returns The parsed Hpricot object, to which you can do what you please. 

    doc = fb.hpricot_get_url '/home.php'

    # File facebook_bot/helper.rb, line 6
 6:   def hpricot_get_url url
 7:     req = try_try_again { @http.get2(url, @opts[:headers]) }
 8:     
 9:     if req.code.to_i != 200
10:       log(req) and return
11:     end
12:     
13:     Hpricot(req.body)
14:   end

log (req)

Logs a bad Net::HTTP request. Appends to a file(log.txt) and prints to the console. 

    # File facebook_bot/helper.rb, line 66
66:   def log req
67:     msg = "ERROR: #{req.code}: #{req.message}\nbody: #{req.body}\nheaders: #{req.response.to_hash.inspect}"
68:     File.open('log.txt','a') do |f|
69:       f.puts msg
70:     end
71:     #puts msg

72:   end

try_try_again () {|| ...}

If at first you don‘t succeed… try try again. This function takes a block and will try(and try and try and try) that block until it finally doesn‘t raise an error. This is useful if you are getting timeouts or other such errors while grabbing some information. I use it liberally just in case I get disconnected temporarily (which is often). 

    # File facebook_bot/helper.rb, line 52
52:   def try_try_again
53:     begin
54:       do_http { yield }
55:     rescue Timeout::Error => err
56:       puts "Timeout Error: #{err}! Retrying.."
57:       retry
58:     rescue Exception => exception
59:       puts "Exception: #{exception.message}! Retrying.."
60:       retry
61:     end
62:   end