# Capybara [![Build Status](https://secure.travis-ci.org/jnicklas/capybara.png)](http://travis-ci.org/jnicklas/capybara) [![Dependency Status](https://gemnasium.com/jnicklas/capybara.png)](https://gemnasium.com/jnicklas/capybara) [![Code Quality](https://codeclimate.com/badge.png)](https://codeclimate.com/github/jnicklas/capybara) Capybara helps you test Rails and Rack applications by simulating how a real user would interact with your app. It is agnostic about the driver running your tests and comes with Rack::Test and Selenium support built in. WebKit is supported through an external gem. **Need help?** Ask on the mailing list (please do not open an issue on GitHub): http://groups.google.com/group/ruby-capybara ## Setup To install, type ```bash sudo gem install capybara ``` If you are using Rails, add this line to your test helper file: ```ruby require 'capybara/rails' ``` If you are not using Rails, set Capybara.app to your rack app: ```ruby Capybara.app = MyRackApp ``` ## Using Capybara with Cucumber The `cucumber-rails` gem comes with Capybara support built-in. If you are not using Rails, manually load the `capybara/cucumber` module: ```ruby require 'capybara/cucumber' Capybara.app = MyRackApp ``` You can use the Capybara DSL in your steps, like so: ```ruby When /I sign in/ do within("#session") do fill_in 'Login', :with => 'user@example.com' fill_in 'Password', :with => 'password' end click_link 'Sign in' end ``` You can switch to the `Capybara.javascript_driver` (`:selenium` by default) by tagging scenarios (or features) with `@javascript`: ```ruby @javascript Scenario: do something Ajaxy When I click the Ajax link ... ``` There are also explicit `@selenium` and `@rack_test` tags set up for you. ## Using Capybara with RSpec Load RSpec 2.x support by adding the following line (typically to your `spec_helper.rb` file): ```ruby require 'capybara/rspec' ``` If you are using Rails, put your Capybara specs in `spec/requests` or `spec/integration`. If you are not using Rails, tag all the example groups in which you want to use Capybara with `:type => :request`. You can now write your specs like so: ```ruby describe "the signup process", :type => :request do before :each do User.make(:email => 'user@example.com', :password => 'caplin') end it "signs me in" do within("#session") do fill_in 'Login', :with => 'user@example.com' fill_in 'Password', :with => 'password' end click_link 'Sign in' end end ``` Use `:js => true` to switch to the `Capybara.javascript_driver` (`:selenium` by default), or provide a `:driver` option to switch to one specific driver. For example: ```ruby describe 'some stuff which requires js', :js => true do it 'will use the default js driver' it 'will switch to one specific driver', :driver => :webkit end ``` Finally, Capybara also comes with a built in DSL for creating descriptive acceptance tests: ```ruby feature "Signing up" do background do User.make(:email => 'user@example.com', :password => 'caplin') end scenario "Signing in with correct credentials" do within("#session") do fill_in 'Login', :with => 'user@example.com' fill_in 'Password', :with => 'caplin' end click_link 'Sign in' end end ``` `feature` is in fact just an alias for `describe ..., :type => :request`, `background` is an alias for `before`, and `scenario` for `it`. ## Using Capybara with Test::Unit * If you are using Rails, add `database_cleaner` to your Gemfile: ```ruby group :test do gem 'database_cleaner' end ``` Then add the following code in your `test_helper.rb` file to make Capybara available in all test cases deriving from `ActionDispatch::IntegrationTest`: ```ruby # Transactional fixtures do not work with Selenium tests, because Capybara # uses a separate server thread, which the transactions would be hidden # from. We hence use DatabaseCleaner to truncate our test database. DatabaseCleaner.strategy = :truncation class ActionDispatch::IntegrationTest # Make the Capybara DSL available in all integration tests include Capybara::DSL # Stop ActiveRecord from wrapping tests in transactions self.use_transactional_fixtures = false teardown do DatabaseCleaner.clean # Truncate the database Capybara.reset_sessions! # Forget the (simulated) browser state Capybara.use_default_driver # Revert Capybara.current_driver to Capybara.default_driver end end ``` * If you are not using Rails, define a base class for your Capybara tests like so: ```ruby class CapybaraTestCase < Test::Unit::TestCase include Capybara::DSL def teardown Capybara.reset_sessions! Capybara.use_default_driver end end ``` Remember to call `super` in any subclasses that override `teardown`. To switch the driver, set `Capybara.current_driver`. For instance, ```ruby class BlogTest < ActionDispatch::IntegrationTest setup do Capybara.current_driver = Capybara.javascript_driver # :selenium by default end test 'shows blog posts' do # ... this test is run with Selenium ... end end ``` ## Using Capybara with MiniTest::Spec Set up your base class as with Test::Unit. (On Rails, the right base class could be something other than ActionDispatch::IntegrationTest.) The capybara_minitest_spec gem ([Github](https://github.com/ordinaryzelig/capybara_minitest_spec), [rubygems.org](https://rubygems.org/gems/capybara_minitest_spec)) provides MiniTest::Spec expectations for Capybara. For example: ```ruby page.must_have_content('Important!') ``` ## Drivers Capybara uses the same DSL to drive a variety of browser and headless drivers. ### Selecting the Driver By default, Capybara uses the `:rack_test` driver, which is fast but does not support JavaScript. You can set up a different default driver for your features. For example if you'd prefer to run everything in Selenium, you could do: ```ruby Capybara.default_driver = :selenium ``` However, if you are using RSpec or Cucumber, you may instead want to consider leaving the faster `:rack_test` as the __default_driver__, and marking only those tests that require a JavaScript-capable driver using `:js => true` or `@javascript`, respectively. By default, JavaScript tests are run using the `:selenium` driver. You can change this by setting `Capybara.javascript_driver`. You can also change the driver temporarily (typically in the Before/setup and After/teardown blocks): ```ruby Capybara.current_driver = :webkit # temporarily select different driver ... tests ... Capybara.use_default_driver # switch back to default driver ``` **Note**: switching the driver creates a new session, so you may not be able to switch in the middle of a test. ### RackTest RackTest is Capybara's default driver. It is written in pure Ruby and does not have any support for executing JavaScript. Since the RackTest driver works directly against the Rack interface, it does not need any server to be started, it can work directly against any Rack app. This means that if your application is not a Rack application (Rails, Sinatra and most other Ruby frameworks are Rack applications) then you cannot use this driver. You cannot use the RackTest driver to test a remote application. [capybara-mechanize](https://github.com/jeroenvandijk/capybara-mechanize) intends to provide a similar driver which works against remote servers, it is a separate project. RackTest can be configured with a set of headers like this: ```ruby Capybara.register_driver :rack_test do |app| Capybara::RackTest::Driver.new(app, :browser => :chrome) end ``` See the section on adding and configuring drivers. ### Selenium At the moment, Capybara supports [Selenium 2.0 (Webdriver)](http://seleniumhq.org/docs/01_introducing_selenium.html#selenium-2-aka-selenium-webdriver), *not* Selenium RC. Provided Firefox is installed, everything is set up for you, and you should be able to start using Selenium right away. **Note**: drivers which run the server in a different thread may not work share the same transaction as your tests, causing data not to be shared between your test and test server, see "Transactions and database setup" below. ### Capybara-webkit The [capybara-webkit driver](https://github.com/thoughtbot/capybara-webkit) is for true headless testing. It uses QtWebKit to start a rendering engine process. It can execute JavaScript as well. It is significantly faster than drivers like Selenium since it does not load an entire browser. You can install it with: ```bash gem install capybara-webkit ``` And you can use it by: ```ruby Capybara.javascript_driver = :webkit ``` ### Poltergeist [Poltergeist](https://github.com/jonleighton/poltergeist) is another headless driver which integrates Capybara with [PhantomJS](http://phantomjs.org/). It is truly headless, so doesn't require Xvfb to run on your CI server. It will also detect and report any Javascript errors that happen within the page. ## The DSL *A complete reference is available at [rubydoc.info](http://rubydoc.info/github/jnicklas/capybara/master)*. **Note**: All searches in Capybara are *case sensitive*. This is because Capybara heavily uses XPath, which doesn't support case insensitivity. ### Navigating You can use the [#visit](http://rubydoc.info/github/jnicklas/capybara/master/Capybara/Session#visit-instance_method) method to navigate to other pages: ```ruby visit('/projects') visit(post_comments_path(post)) ``` The visit method only takes a single parameter, the request method is **always** GET. You can get the [current path](http://rubydoc.info/github/jnicklas/capybara/master/Capybara/Session#current_path-instance_method) of the browsing session for test assertions: ```ruby current_path.should == post_comments_path(post) ``` ### Clicking links and buttons *Full reference: [Capybara::Node::Actions](http://rubydoc.info/github/jnicklas/capybara/master/Capybara/Node/Actions)* You can interact with the webapp by following links and buttons. Capybara automatically follows any redirects, and submits forms associated with buttons. ```ruby click_link('id-of-link') click_link('Link Text') click_button('Save') click_on('Link Text') # clicks on either links or buttons click_on('Button Value') ``` ### Interacting with forms *Full reference: [Capybara::Node::Actions](http://rubydoc.info/github/jnicklas/capybara/master/Capybara/Node/Actions)* There are a number of tools for interacting with form elements: ```ruby fill_in('First Name', :with => 'John') fill_in('Password', :with => 'Seekrit') fill_in('Description', :with => 'Really Long Text...') choose('A Radio Button') check('A Checkbox') uncheck('A Checkbox') attach_file('Image', '/path/to/image.jpg') select('Option', :from => 'Select Box') ``` ### Querying *Full reference: [Capybara::Node::Matchers](http://rubydoc.info/github/jnicklas/capybara/master/Capybara/Node/Matchers)* Capybara has a rich set of options for querying the page for the existence of certain elements, and working with and manipulating those elements. ```ruby page.has_selector?('table tr') page.has_selector?(:xpath, '//table/tr') page.has_no_selector?(:content) page.has_xpath?('//table/tr') page.has_css?('table tr.foo') page.has_content?('foo') ``` **Note:** The negative forms like `has_no_selector?` are different from `not has_selector?`. Read the section on asynchronous JavaScript for an explanation. You can use these with RSpec's magic matchers: ```ruby page.should have_selector('table tr') page.should have_selector(:xpath, '//table/tr') page.should have_no_selector(:content) page.should have_xpath('//table/tr') page.should have_css('table tr.foo') page.should have_content('foo') ``` ### Finding _Full reference: [Capybara::Node::Finders](http://rubydoc.info/github/jnicklas/capybara/master/Capybara/Node/Finders)_ You can also find specific elements, in order to manipulate them: ```ruby find_field('First Name').value find_link('Hello').visible? find_button('Send').click find(:xpath, "//table/tr").click find("#overlay").find("h1").click all('a').each { |a| a[:href] } ``` **Note**: `find` will wait for an element to appear on the page, as explained in the Ajax section. If the element does not appear it will raise an error. These elements all have all the Capybara DSL methods available, so you can restrict them to specific parts of the page: ```ruby find('#navigation').click_link('Home') find('#navigation').should have_button('Sign out') ``` ### Scoping Capybara makes it possible to restrict certain actions, such as interacting with forms or clicking links and buttons, to within a specific area of the page. For this purpose you can use the generic [within](http://rubydoc.info/github/jnicklas/capybara/master/Capybara/Session#within-instance_method) method. Optionally you can specify which kind of selector to use. ```ruby within("li#employee") do fill_in 'Name', :with => 'Jimmy' end within(:xpath, "//li[@id='employee']") do fill_in 'Name', :with => 'Jimmy' end ``` **Note**: `within` will scope the actions to the _first_ (not _any_) element that matches the selector. There are special methods for restricting the scope to a specific fieldset, identified by either an id or the text of the fieldset's legend tag, and to a specific table, identified by either id or text of the table's caption tag. ```ruby within_fieldset('Employee') do fill_in 'Name', :with => 'Jimmy' end within_table('Employee') do fill_in 'Name', :with => 'Jimmy' end ``` ### Scripting In drivers which support it, you can easily execute JavaScript: ```ruby page.execute_script("$('body').empty()") ``` For simple expressions, you can return the result of the script. Note that this may break with more complicated expressions: ```ruby result = page.evaluate_script('4 + 4'); ``` ### Saving screenshot In drivers which support it, you can save screenshot: ```ruby page.save_screenshot('screenshot.png') ``` ### Debugging It can be useful to take a snapshot of the page as it currently is and take a look at it: ```ruby save_and_open_page ``` You can also retrieve the current state of the DOM as a string using [page.html](http://rubydoc.info/github/jnicklas/capybara/master/Capybara/Session#html-instance_method). ```ruby print page.html ``` This is mostly useful for debugging. You should avoid testing against the contents of `page.html` and use the more expressive finder methods instead. ## Transactions and database setup Some Capybara drivers need to run against an actual HTTP server. Capybara takes care of this and starts one for you in the same process as your test, but on another thread. Selenium is one of those drivers, whereas RackTest is not. If you are using a SQL database, it is common to run every test in a transaction, which is rolled back at the end of the test, rspec-rails does this by default out of the box for example. Since transactions are usually not shared across threads, this will cause data you have put into the database in your test code to be invisible to Capybara. Cucumber handles this by using truncation instead of transactions, i.e. they empty out the entire database after each test. You can get the same behaviour by using a gem such as [database_cleaner](https://github.com/bmabey/database_cleaner). It is also possible to force your ORM to use the same transaction for all threads. This may have thread safety implications and could cause strange failures, so use caution with this approach. It can be implemented in ActiveRecord through the following monkey patch: ```ruby class ActiveRecord::Base mattr_accessor :shared_connection @@shared_connection = nil def self.connection @@shared_connection || retrieve_connection end end ActiveRecord::Base.shared_connection = ActiveRecord::Base.connection ``` ## Asynchronous JavaScript (Ajax and friends) When working with asynchronous JavaScript, you might come across situations where you are attempting to interact with an element which is not yet present on the page. Capybara automatically deals with this by waiting for elements to appear on the page. When issuing instructions to the DSL such as: ```ruby click_link('foo') click_link('bar') page.should have_content('baz') ``` If clicking on the *foo* link triggers an asynchronous process, such as an Ajax request, which, when complete will add the *bar* link to the page, clicking on the *bar* link would be expected to fail, since that link doesn't exist yet. However Capybara is smart enought to retry finding the link for a brief period of time before giving up and throwing an error. The same is true of the next line, which looks for the content *baz* on the page; it will retry looking for that content for a brief time. You can adjust how long this period is (the default is 2 seconds): ```ruby Capybara.default_wait_time = 5 ``` Be aware that because of this behaviour, the following two statements are **not** equivalent, and you should **always** use the latter! ```ruby !page.has_xpath?('a') page.has_no_xpath?('a') ``` The former would immediately fail because the content has not yet been removed. Only the latter would wait for the asynchronous process to remove the content from the page. Capybara's Rspec matchers, however, are smart enough to handle either form. The two following statements are functionally equivalent: ```ruby page.should_not have_xpath('a') page.should have_no_xpath('a') ``` Capybara's waiting behaviour is quite advanced, and can deal with situations such as the following line of code: ```ruby find('#sidebar').find('h1').should have_content('Something') ``` Even if JavaScript causes `#sidebar` to disappear off the page, Capybara will automatically reload it and any elements it contains. So if an AJAX request causes the contents of `#sidebar` to change, which would update the text of the `h1` to "Something", and this happened, this test would pass. If you do not want this behaviour, you can set `Capybara.automatic_reload` to `false`. ## Using the DSL elsewhere You can mix the DSL into any context by including Capybara::DSL: ```ruby require 'capybara' require 'capybara/dsl' Capybara.default_driver = :webkit module MyModule include Capybara::DSL def login! within("//form[@id='session']") do fill_in 'Login', :with => 'user@example.com' fill_in 'Password', :with => 'password' end click_link 'Sign in' end end ``` This enables its use in unsupported testing frameworks, and for general-purpose scripting. ## Calling remote servers Normally Capybara expects to be testing an in-process Rack application, but you can also use it to talk to a web server running anywhere on the internets, by setting app_host: ```ruby Capybara.current_driver = :selenium Capybara.app_host = 'http://www.google.com' ... visit('/') ``` **Note**: the default driver (`:rack_test`) does not support running against a remote server. With drivers that support it, you can also visit any URL directly: ```ruby visit('http://www.google.com') ``` By default Capybara will try to boot a rack application automatically. You might want to switch off Capybara's rack server if you are running against a remote application: ```ruby Capybara.run_server = false ``` ## Using the sessions manually For ultimate control, you can instantiate and use a [Session](http://rubydoc.info/github/jnicklas/capybara/master/Capybara/Session) manually. ```ruby require 'capybara' session = Capybara::Session.new(:webkit, my_rack_app) session.within("//form[@id='session']") do session.fill_in 'Login', :with => 'user@example.com' session.fill_in 'Password', :with => 'password' end session.click_link 'Sign in' ``` ## XPath, CSS and selectors Capybara does not try to guess what kind of selector you are going to give it, and will always use CSS by default. If you want to use XPath, you'll need to do: ```ruby within(:xpath, '//ul/li') { ... } find(:xpath, '//ul/li').text find(:xpath, '//li[contains(.//a[@href = "#"]/text(), "foo")]').value ``` Alternatively you can set the default selector to XPath: ```ruby Capybara.default_selector = :xpath find('//ul/li').text ``` Capybara allows you to add custom selectors, which can be very useful if you find yourself using the same kinds of selectors very often: ```ruby Capybara.add_selector(:id) do xpath { |id| XPath.descendant[XPath.attr(:id) == id.to_s] } end Capybara.add_selector(:row) do xpath { |num| ".//tbody/tr[#{num}]" } end Capybara.add_selector(:flash_type) do css { |type| "#flash.#{type}" } end ``` The block given to xpath must always return an XPath expression as a String, or an XPath expression generated through the XPath gem. You can now use these selectors like this: ```ruby find(:id, 'post_123') find(:row, 3) find(:flash_type, :notice) ``` You can specify an optional match option which will automatically use the selector if it matches the argument: ```ruby Capybara.add_selector(:id) do xpath { |id| XPath.descendant[XPath.attr(:id) == id.to_s] } match { |value| value.is_a?(Symbol) } end ``` Now use it like this: ```ruby find(:post_123) ``` This :id selector is already built into Capybara by default, so you don't need to add it yourself. ## Beware the XPath // trap In XPath the expression // means something very specific, and it might not be what you think. Contrary to common belief, // means "anywhere in the document" not "anywhere in the current context". As an example: ```ruby page.find(:xpath, '//body').all(:xpath, '//script') ``` You might expect this to find all script tags in the body, but actually, it finds all script tags in the entire document, not only those in the body! What you're looking for is the .// expression which means "any descendant of the current node": ```ruby page.find(:xpath, '//body').all(:xpath, './/script') ``` The same thing goes for within: ```ruby within(:xpath, '//body') do page.find(:xpath, './/script') within(:xpath, './/table/tbody') do ... end end ``` ## Configuring and adding drivers Capybara makes it convenient to switch between different drivers. It also exposes an API to tweak those drivers with whatever settings you want, or to add your own drivers. This is how to switch the selenium driver to use chrome: ```ruby Capybara.register_driver :selenium do |app| Capybara::Selenium::Driver.new(app, :browser => :chrome) end ``` However, it's also possible to give this a different name, so tests can switch between using different browsers effortlessly: ```ruby Capybara.register_driver :selenium_chrome do |app| Capybara::Selenium::Driver.new(app, :browser => :chrome) end ``` Whatever is returned from the block should conform to the API described by Capybara::Driver::Base, it does not however have to inherit from this class. Gems can use this API to add their own drivers to Capybara. The [Selenium wiki](http://code.google.com/p/selenium/wiki/RubyBindings) has additional info about how the underlying driver can be configured. ## Gotchas: * Access to session and request is not possible from the test, Access to response is limited. Some drivers allow access to response headers and HTTP status code, but this kind of functionality is not provided by some drivers, such as Selenium. * Access to Rails specific stuff (such as `controller`) is unavailable, since we're not using Rails' integration testing. * Freezing time: It's common practice to mock out the Time so that features that depend on the current Date work as expected. This can be problematic, since Capybara's Ajax timing uses the system time, resulting in Capybara never timing out and just hanging when a failure occurs. It's still possible to use gems which allow you to travel in time, rather than freeze time. One such gem is [Timecop](http://github.com/jtrupiano/timecop). * When using Rack::Test, beware if attempting to visit absolute URLs. For example, a session might not be shared between visits to `posts_path` and `posts_url`. If testing an absolute URL in an Action Mailer email, set `default_url_options` to match the Rails default of `www.example.com`. ## Development If you found a _reproducible_ bug, open a [GitHub Issue](http://github.com/jnicklas/capybara/issues) to submit a bug report. Even better, send a pull request! Make sure all changes are well tested, Capybara is a testing tool after all. Topic branches are good. To set up a development environment, simply do: ```bash git submodule update --init bundle install bundle exec rake # run the test suite ```