To date, a lot of interesting applications have been built on top of the Twitter service with new apps being released almost daily, each one more ingenious than the last.

In my spare time I’ve been tinkering with Ruby, my motivation being to learn something new and to see if Ruby lives up the hype that has been surrounding it in recent years. In conjunction with this I’ve also been experimenting with obtaining content from existing web sites and services, content being king after all.

On my list of software development goals I’ve wanted to do something with Twitter but have been lacking the all important idea of which problem to solve. Considering my learning objectives I decided to just get stuck in and see what basic task I could accomplish that involved:

1. authenticating to the service
2. making a request
3. processing the response

After looking at the API retrieving the list of followers for a given account seemed doable.

If I were to undertake a non-trivial Twitter application I’d consider using Twitter4R rather than writing all the REST interaction from the ground up. Another possibility would be to request JSON rather than parsing XML with Hpricot. The luxury of decisions.

The result of my tinkering is followers.rb which lists the followers of the account accessed with USERNAME:PASSWORD credentials:

#!/usr/bin/env ruby

followers.rb

retrieve list of followers from Twitter

SJW

require ’net/http' require ‘base64’ require ‘rubygems’ require ‘hpricot’

user = ‘USERNAME’ pass = ‘PASSWORD’ host = ’twitter.com’; path = ‘/statuses/followers.xml’

auth = ‘Basic ’ + Base64.encode64("#{user}:#{pass}").delete("\n")

authenicate and retrieve XML, feeding it into Hpricot

doc = ’’ Net::HTTP.start(host) do |http| res = http.get(path, ‘Authorization’ => auth) unless res.code == ‘200’ puts “An error occured” exit end doc = Hpricot(res.body) end

each follower is within a users = doc/:user

count the number of followers

count = “#{users.length} followers:” puts count count.length.times {print ‘-’} puts “\n\n”

output each name and corresponding twitter account name

users.each do |u| name = (u/:name).text screen_name = (u/:screen_name).text puts “#{name} | @#{screen_name}” end