The Wikipedia API blows, writing this was faster

wikiscraper.rb

require 'open-uri'
require 'nokogiri'

# Scrapes wikipedia content for stack
# The API blows, writing this was faster
class WikiImporter

  # Words rejected will excluded from the results
  REJECT_WORDS = [
                    "Comparison of web application frameworks",
                    "List of Ajax frameworks",
                    "Web application framework",
                    "Template:Application frameworks",
                    "Debuggers",
                    "Emulator",
                    "Integrated development environment"
                ]

  attr_accessor :url, :doc

  def initialize(url = nil)
    @url = url
  end

  # Fetches the document and creates a document
  # @param  [String] url to fetch from
  # @return [Nokogiri::Document]
  def doc(url = @url)
    @doc ||= Nokogiri::HTML(open(url))
  end

  # Fetches the content for the provided url
  # and returns the content
  # @param [String] url to fetch the document
  # @param &blk yeilds the block and retrieves the contents from the yeilded
  # @yieldparam [Nokogiri::Document]
  # @returns [Array] content elements
  def self.content_for(url, &blk)
    yield(WikiImporter.new(url).doc)
    .map(&:content)
    .compact
    .uniq
    .reject do |name|
      REJECT_WORDS.include?(name)
    end
  end

  # @return [Array] List of Programming Languages
  def self.programing_languages(url = 'http://en.wikipedia.org/w/index.php?title=List_of_programming_languages&printable=yes')
    content_for url do |doc|
      doc.css('#mw-content-text .multicol a')
    end
  end

  # @return [Array] List of Web Application Frameworks
  def self.webapp_frameworks(url = 'http://en.wikipedia.org/w/index.php?title=Category:Web_application_frameworks&printable=yes')
    content_for url do |doc|
      doc.css('#mw-pages .mw-content-ltr a')
    end
  end

  # @return [Array] List of Mobile app platforms
  def self.mobile_app_development(url = 'http://en.wikipedia.org/w/index.php?title=Mobile_application_development&printable=yes')
    content_for url do |doc|
      doc.css('#mw-content-text .wikitable th a')
    end
  end
end