follow from coderwall leaderboard

app.rb

require 'bundler/setup'
Bundler.require(:default) if defined?(Bundler)

@config ||= YAML.load_file 'config_twitter.yml'
targets = [
  'http://coderwall.com/teams/4f27193d973bf0000400029d',
  'http://coderwall.com/teams/4f271946973bf000040004a1',
  'http://coderwall.com/teams/4f271948973bf00004000515',
  'http://coderwall.com/teams/4f271945973bf00004000463',
  'http://coderwall.com/teams/4f5fe57e7d4152000d000002',
  'http://coderwall.com/teams/4f271966973bf00004000ab0',
]

a = Mechanize.new

users = []
targets.each do |t|
  a.get(t).search('.button.seemore.track').map do |prof|
    users << prof['href'].delete('/')
  end
end

Twitter.configure do |config|
  config.consumer_key = @config['consumer_key']
  config.consumer_secret = @config['consumer_secret']
  config.oauth_token = @config['access_token']
  config.oauth_token_secret = @config['access_secret']
end

notfounds = []
users.each do |u|
  begin
    Twitter.follow(u) if Twitter.user(u)
  rescue Twitter::Error::NotFound
    notfounds << u
  end
end
puts notfounds.join("\n")

config_twitter.yml

consumer_key: ""
consumer_secret: ""
access_token: ""
access_secret: ""

Gemfile

source "https://rubygems.org"

gem 'mechanize'
gem 'twitter'