gravatar_fetcher.rb

require 'digest/sha1'
require 'net/http'
class GravatarFetcher
  # Gravatar is a bit stupid, in that there's
  # no way to tell if they're returning the default
  # avatar - here's a hack to do that.
  class << self
    def fetch(email, size=60)
      email_hash = Digest::MD5.hexdigest(email)
      http = Net::HTTP.new("www.gravatar.com", 80)
      res = http.start {
        req = Net::HTTP::Get.new("/avatar.php?gravatar_id=#{email_hash}&s=#{size}&d=foo")
        http.request(req)
      }
      res.is_a?(Net::HTTPSuccess) ? res.body : nil
    end
  end
end