Tarantula is a big fuzzy spider. It crawls your Rails 2.3 and 3.x applications, fuzzing data to see what breaks.

<img src=“https://secure.travis-ci.org/relevance/tarantula.png” />

The latest and greatest version is always available on GitHub. (See the rakefile for dependencies, or just let RubyGems handle it). Add it to your Gemfile as normal:

gem "tarantula"

Or for Rails 3 applications:

gem 'tarantula', :require => 'tarantula-rails3'

Use the included rake task to create a Rails integration test that will allow Tarantula to crawl your app.

$ rake tarantula:setup

Take a moment to familiarize yourself with the generated test. If parts of your application require login, update the test to make sure Tarantula can access those parts of your app.

require "relevance/tarantula"
require "test_helper"

class TarantulaTest < ActionController::IntegrationTest
  # Load enough test data to ensure that there's a link to every page in your
  # application. Doing so allows Tarantula to follow those links and crawl
  # every page.  For many applications, you can load a decent data set by
  # loading all fixtures.
  fixtures :all

  def test_tarantula
    # If your application requires users to log in before accessing certain
    # pages, uncomment the lines below and update them to allow this test to
    # log in to your application.  Doing so allows Tarantula to crawl the
    # pages that are only accessible to logged-in users.
    #
    #   post '/session', :login => 'quentin', :password => 'monkey'
    #   follow_redirect!

    tarantula_crawl(self)
  end
end

If you want to set custom options, you can get access to the crawler and set properties before running it. For example, this would turn on HTMLTidy.

def test_tarantula
  post '/session', :login => 'kilgore', :password => 'trout'
  assert_response :redirect
  assert_redirected_to '/'
  follow_redirect!

  t = tarantula_crawler(self)
  t.handlers << Relevance::Tarantula::TidyHandler.new
  t.crawl '/'
end

Now it’s time to turn Tarantula loose on your app. Assuming your project is at /work/project/:

$ cd /work/project
$ rake tarantula:test

If you run the test using the steps shown above, Tarantula will produce a report in tmp/tarantula. You can also set VERBOSE=true to see more detail as the test runs.

For more options, please see the test suite.

If, for example, a 404 is an appropriate response for some URLs, you can tell Tarantula to allow 404s for URLs matching a given regex:

t = tarantula_crawler(self)
t.allow_404_for %r{/users/\d+/}

You can specify the attack strings that Tarantula throws at your application.

def test_tarantula
  t = tarantula_crawler(self)

  Relevance::Tarantula::FormSubmission.attacks << { 
    :name => :xss,
    :input => "<script>gotcha!</script>",
    :output => "<script>gotcha!</script>",
  }

  Relevance::Tarantula::FormSubmission.attacks << { 
    :name => :sql_injection,
    :input => "a'; DROP TABLE posts;",
  }

  t.handlers << Relevance::Tarantula::AttackHandler.new
  t.times_to_crawl = 2
  t.crawl "/posts"
end

This example adds custom attacks for both SQL injection and XSS. It also tells Tarantula to crawl the app 2 times. This is important for XSS attacks because the results won’t appear until the second time Tarantula performs the crawl.

You can specify a timeout for each specific crawl that Tarantula runs. For example:

def test_tarantula
  t = tarantula_crawler(self)
  t.times_to_crawl = 2
  t.crawl_timeout = 5.minutes
  t.crawl "/"
end

The above will crawl your app twice, and each specific crawl will timeout if it takes longer then 5 minutes. You may need a timeout to keep the tarantula test time reasonable if your app is large or just happens to have a large amount of ‘never-ending’ links, such as with an any sort of “auto-admin” interface.

Please submit your bug reports, patches, or feature requests in Github Issues.

Tarantula is released under the MIT license.