Capybara aims to simplify the process of integration testing Rack applications, such as Rails, Sinatra or Merb. Capybara simulates how a real user would interact with a web application. It is agnostic about the driver running your tests and currently comes bundled with rack-test, Culerity, Celerity and Selenium support built in. env.js support is available as the capybara-envjs gem.
A complete reference is available at at rubydoc.info.
Install as a gem:
sudo gem install capybara
On OSX you may have to install libffi, you can install it via MacPorts with:
sudo port install libffi
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Source hosted at GitHub.
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Please direct questions, discussions at the mailing list.
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Report issues on GitHub Issues
Pull requests are very welcome! Make sure your patches are well tested, Capybara is a testing tool after all. Please create a topic branch for every separate change you make.
Capybara uses bundler in development. To set up a development environment, simply do:
git submodule update --init gem install bundler --pre bundle install
Capybara is built to work nicely with Cucumber. Support for Capybara is built into cucumber-rails. In your Rails app, just run:
rails generate cucumber:install --capybara
And everything should be set up and ready to go.
If you want to use Capybara with Cucumber outside Rails (for example with Merb or Sinatra), you’ll need to require Capybara and set the Rack app manually:
require 'capybara/cucumber' Capybara.app = MyRackApp
Now you can use it in your steps:
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
Capybara sets up some tags for you to use in Cucumber. Often you’ll want to run only some scenarios with a driver that supports JavaScript, Capybara makes this easy: simply tag the scenario (or feature) with @javascript
:
@javascript Scenario: do something AJAXy When I click the AJAX link ...
You can change which driver Capybara uses for JavaScript:
Capybara.javascript_driver = :culerity
There are also explicit @selenium
, @culerity
and @rack_test
tags set up for you.
If you prefer RSpec to using Cucumber, you can use the built in RSpec support by adding the following line (typically to your spec_helper.rb
file):
require 'capybara/rspec'
You can now use it in your examples:
describe "the signup process", :type => :request do 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
Capybara is only included for examples with :type => :request
(or :acceptance
for compatibility).
Note that if you use the rspec-rails
gem, :type => :request
is automatically set on all files under spec/requests
(and also spec/integration
), so that’s a good directory to place your Capybara specs in. rspec-rails
will also automatically include Capybara in :controller
and :mailer
examples.
RSpec’s metadata feature can be used to switch to a different driver. Use :js => true
to switch to the javascript driver, or provide a :driver
option to switch to one specific driver. For example:
describe 'some stuff which requires js', :js => true do it 'will use the default js driver' it 'will switch to one specific driver', :driver => :celerity end
Capybara also comes with a built in DSL for creating descriptive acceptance tests:
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
Note that Capybara’s built in RSpec support only works with RSpec 2.0 or later. You’ll need to roll your own for earlier versions of RSpec.
You can use the built-in Rails support to easily get Capybara running with Rails:
require 'capybara/rails'
If you’re using Capybara with a non-Rails Rack application, set Capybara.app
to your application class:
Capybara.app = MyRackApp
You can set up a default driver for your features. For example if you’d prefer to run Selenium, you could do:
Capybara.default_driver = :selenium
You can change the driver temporarily:
Capybara.current_driver = :culerity Capybara.use_default_driver
You can do this in Before and After blocks to temporarily switch to a different driver. Note that switching driver creates a new session, so you may not be able to switch in the middle of a Scenario.
At the moment, Capybara supports Webdriver, also called Selenium 2.0, not Selenium RC. Provided Firefox is installed, everything is set up for you, and you should be able to start using Selenium right away.
Celerity only runs on JRuby, so you’ll need to install the celerity gem under JRuby:
jruby -S gem install celerity
Install celerity as noted above, make sure JRuby is in your path. Note that Culerity doesn’t seem to be working under Ruby 1.9 at the moment.
The capybara-envjs driver uses the envjs gem (GitHub, rubygems.org) to interpret JavaScript outside the browser. The driver is installed by installing the capybara-envjs gem:
gem install capybara-envjs
More info about the driver and env.js are available through the links above. The envjs gem only supports Ruby 1.8.7 at this time.
Capybara’s DSL (domain-specific language) is inspired by Webrat. While backwards compatibility is retained in a lot of cases, there are certain important differences. Unlike in Webrat, all searches in Capybara are *case sensitive*. This is because Capybara heavily uses XPath, which doesn’t support case insensitivity.
For a full reference of the DSL, check Capybara::Session and the modules defined in Capybara::Node.
You can use the {visit
} method to navigate to other pages:
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 of the browsing session for test assertions:
current_path.should == post_comments_path(post)
You can interact with the webapp by following links and buttons. Capybara automatically follows any redirects, and submits forms associated with buttons.
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')
Forms are everywhere in webapps, there are a number of tools for interacting with the various form elements (see Capybara::Node::Actions):
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')
Capybara has a rich set of options for querying the page for the existence of certain elements, and working with and manipulating those elements (see Capybara::Node::Matchers).
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')
You can use these with RSpec’s magic matchers:
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') page.should have_no_content('foo')
Note that page.should have_no_xpath
is preferred over page.should_not have_xpath
. Read the section on asynchronous JavaScript for an explanation.
You can also find specific elements, in order to manipulate them (see Capybara::Node::Finders):
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 that 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:
find('#navigation').click_link('Home') find('#navigation').should have_button('Sign out')
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
} method. Optionally you can specify which kind of selector to use.
within("li#employee") do fill_in 'Name', :with => 'Jimmy' end within(:xpath, "//li[@id='employee']") do fill_in 'Name', :with => 'Jimmy' end
There are special methods for restricting the scope to a specific fieldset, identified by either an id or the text of the fieldet’s legend tag, and to a specific table, identified by either id or text of the table’s caption tag.
within_fieldset('Employee') do fill_in 'Name', :with => 'Jimmy' end within_table('Employee') do fill_in 'Name', :with => 'Jimmy' end
In drivers which support it, you can easily execute JavaScript:
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:
result = page.evaluate_script('4 + 4');
It can be useful to take a snapshot of the page as it currently is and take a look at it:
save_and_open_page
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:
click_link('foo') click_link('bar') page.should have_content('baz')
If clicking on the foo link causes 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 expeced 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):
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!
page.should_not have_xpath('a') page.should have_no_xpath('a')
The former would incorrectly wait for the content to appear, since the asynchronous process has not yet removed the element from the page, it would therefore fail, even though the code might be working correctly. The latter correctly waits for the element to disappear from the page.
You can mix the DSL into any context, for example you could use it in RSpec examples. Just load the DSL and include it anywhere:
require 'capybara' require 'capybara/dsl' Capybara.default_driver = :culerity module MyModule include Capybara 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
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:
Capybara.current_driver = :selenium Capybara.app_host = 'http://www.google.com' ... visit('/')
Note that rack-test does not support running against a remote server. With drivers that support it, you can also visit any URL directly:
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:
Capybara.run_server = false
For ultimate control, you can instantiate and use a session manually.
require 'capybara' session = Capybara::Session.new(:culerity, 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'
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:
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:
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:
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
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:
find(:id, 'post_123') find(:row, 3)
You can specify an optional match option which will automatically use the selector if it matches the argument:
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:
find(:post_123)
This :id selector is already built into Capybara by default, so you don’t need to add it yourself.
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:
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”:
page.find(:xpath, '//body').all(:xpath, './/script')
The same thing goes for within:
within(:xpath, '//body') do page.find(:xpath, './/script') within(:xpath, './/table/tbody') do ... end end
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:
Capybara.register_driver :selenium do |app| Capybara::Driver::Selenium.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:
Capybara.register_driver :selenium_chrome do |app| Capybara::Driver::Selenium.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 has additional info about how the underlying driver can be configured.
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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.
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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 plugins which allow you to travel in time, rather than freeze time. One such plugin is Timecop.
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When using Rack::Test, beware if attempting to visit absolute URLs. For example, a session might not be shared between visits to
posts_path
andposts_url
. If testing an absolute URL in an Action Mailer email, setdefault_url_options
to match the Rails default ofwww.example.com
.
(The MIT License)
Copyright © 2009 Jonas Nicklas
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the ‘Software’), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED ‘AS IS’, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.