PageMagic
PageMagic is an API for testing web applications.
It has a simple but powerful DSL which makes modelling and interacting with your pages easy.
Wouldn't it be great if there was a framework that could:
- Model your pages
- Fluently define event hooks / waiters on page elements
- Map paths to pages so that the correct page object is loaded as you navigate
- Be super dynamic
Well PageMagic might just be the answer!
Give it a try and let us know what you think! There will undoubtedly be things that can be improved and issues that we are not aware of so your feedback/pull requests are greatly appreciated!
##Under the hood Under the hood PageMagic uses the totally brilliant Capybara to benefit from its amazing cross browser support.
PageMagic builds on top of Capybara to build resuable models for webpages and website structure.
##What about the other PageObject frameworks out there? PageMagic isn't the first PageObject framework to be written, indeed there are others out there that are totaly awesome e.g:
Whilst these APIs are great, PageMagic goes much further in the power it provides for:
- modelling pages and page components
- defining the wait logic and watchers that are required to build robust page objects that work reliably with javascript rich webpages.
- Supporting page transitions
Check it out :)
Contents
- Installation
- Quick Start
- Defining Pages
- Elements
- Singlular Results
- Multiple Results
- Interacting with elements
- Sub elements
- Custom elements
- Hooks
- Element event hooks
- On load hook
- Helper Methods
- Dynamic Selectors
- Elements
- Starting a session
- Using an existing session
- Rack applications and Rack::Test
- Page mapping
- Mapping against query string parameters
- Mapping against fragment identifiers
- Loading pages/elements from source
- Watchers
- Method watchers
- Simple watchers
- Custom watchers
- Waiting
- Drivers
- Cucumber Quick Start
Installation
gem install page_magic
Quick Start
Getting started with PageMagic is easy, try running this:
require 'page_magic'
class Github
include PageMagic
url 'https://www.github.com'
text_field :search_field, name: 'q' do
watch(:url)
after_events do
wait_until { changed?(:url) }
end
end
def search(project_name)
search_field.set "#{project_name}\n"
end
end
github = Github.visit(browser: :chrome)
github.search('page_magic')
This example defines a page to represent Github's home page, visits it and performs a search.
This code models a single page and will let you interact with the elements defined on it as well as use the helper method we defined.
You can do lots with PageMagic including mapping pages to a session so that they are fluidly switched in for you. You can even define hooks to run when ever a element is interacted with. So what are you wating for? there's no place better to start than the beginning. Have fun! :)
Defining Pages
To define something that PageMagic can work with, simply include PageMagic in to a class.
class Github
include PageMagic
end
Elements
Defining elements is easy. Just give the:
- element_type
- id to refer to it by
- selector to find it in the page
The following example defines a text field called 'search_field' that can be found using its name which is 'q'
class Github
include PageMagic
text_field :search_field, name: 'q'
end
Element types supported by PageMagic are:
- text_field
- button
- link
- checkbox
- select_list
- radio
- textarea
PageMagic is very powerful and provides a number of different ways to define a page element so for more details please look at the API
Singular Results
The element types written above are the method names you need to use in order to define elements of those types on your pages.
Using them as they are written above will tell PageMagic to expect to find only one element using the selector you supply. Finding more than one result will cause PageMagic to raise an AmbiguousQueryException
Multiple Results
Applying an 's' to the end of the element definition method name will tell PageMagic that more than one result can be returned using the given selector.
results are returned in an Array
.
class ResultsPage
include PageMagic
elements :results, css: '.repo-list-item'
end
page.results #=> Array<Element>
Interacting with elements
class Github
include PageMagic
text_field :search_field, name: 'q'
end
Elements are defined with an id which is the name of the method you will use to reference it. In the above example,
the text field was defined with the id :search_field
.
After visiting a page you are will get a Session
object. Elements can be accessed through the session itself.
page.search_field.set 'page_magic'
PageMagic sits on top of Capybara and ultimately returns capybara elements elements for you interact with. Interacting with the element types above is done by calling the following methods:
element | method |
---|---|
text_field | set(String) |
checkbox | set(Boolean) |
radio | choose(String) |
link | click |
text_area | set(String) |
select_list | select(String) |
Typically you will not need to know much about Capybara itself but there will be times when you want to interact with elements at a lower level.In this case please see Capybara's API For more information.
Sub Elements
If your pages are complex you can use PageMagic to compose pages, their elements and subelements to as many levels as you need to.
class ResultsPage
include PageMagic
element :results, css: '.repo-list-item' do
element :stats, css: '.repo-list-stats'
element :meta_data, css: '.repo-list-meta'
link :repo_link, css: 'h3 a'
end
end
Sub elements can be accessed through their parent elements e.g:
page.results.first.repo_link.click
Custom elements
PageMagic allows you to define your own custom elements.
class SearchField < PageMagic::Element
selector name: 'q'
# custom stuff
end
class Github
include PageMagic
element SearchField
end
If an id is not specified then the name of the element class will be used. In the above example the name given to the element of type SearchField
would be search_field
. The selector for the element can bespecified on the class itself or overiden when defining the element. The custom element can also be extended as with other elements.
class MyPage
include PageMagic
element SearchField, :search, selector: '.custom' do
link(:extr_link, id: 'extra-link')
do
end
Hooks
PageMagic provides hooks to allow you to define actions that are executed when you pages and elements are interacted with.
Note:
- You may well find PageMagic's watchers useful.
- The following examples wait for actions to happen. You can of course write you own wait code or feel free try out our wait_until helper:)
On load hook
PageMagic lets you define an on_load hook for your pages. This will be executed when the browser thinks the page has been loaded.
class Github
# ... code defining elements as shown above
on_load do
# code that needs to run when the page has loaded
end
end
Element event hooks
Frequently, you are going to have to work with pages that make heavy use of ajax. For these occasions PageMagic provides before_events
and after_events
hooks that you use to perform custom action.
In the following example we have added watchers and event hooks to the SearchField custom element we defined in the previous section. Encapsulating the business logic here means that we can really add value to the pages that reuse this custom element
class SearchField < PageMagic::Element
selector name: 'q'
watch(:url)
after_events do
wait_until { changed?(:url) }
end
end
Helper methods
Helper methods can be defined to avoid writing repetive page/element specific code outside of your pages and elements.
class Github
# ... code defining elements as shown above
def search(project_name)
search_field.set "#{project_name}\n"
end
end
We can interact with helper in the same way as we did page elements.
page.search('page_magic')
Dynamic Selectors
In some cases you wont be able to specify the selector for an element until runtime. PageMagic allows you to handle such situations with support for dynamic selectors. In the case of our Github example it would be nice to select a particular result by supplying the owners organisation name.
class ResultsPage
include PageMagic
element :results do |organisation:|
selector xpath: "//h3/a[contains(text(), '#{organisation}')]/../.."
# code for sub elements
end
end
In the above example the selector looks for an element that has a link containing text that includes that organisation. The example uses a named parameter and is invoked as follows.
page.results(organisation: 'lvlup')
Starting a session
To start a PageMagic session simply decide what browser you want to use and pass it to PageMagic's .session
method
session = PageMagic.session(browser: :chrome, url: 'https://www.github.com')
Your session won't do much besides navigating to the given url until you have mapped pages to it, so take a look at this next!
Note PageMagic supports having multiple sessions using different browsers at the same time :)
Using an existing session
If you are introducing PageMagic in to a test suite that already makes use of Capybara, PageMagic can be configured to make use of the session that is already configure like this:
session = PageMagic.session(session: Capybara.current_session)
Rack applications and Rack::Test
To run a session against a rack application instead of a live site, simply supply the rack application when creating the session
session = PageMagic.session(application: YourRackApp, url: '/path_to_start_at')
By default PageMagic uses the Rack::Test driver for capybara however you are free to use any browser you like as long as the driver is registered for it.
session = PageMagic.session(application: YourRackApp, browser: :your_chosen_browser, url: '/path_to_start_at')
Out of the box, PageMagic supports the following as parameters to browser:
- :chrome
- :firefox
- :poltergeist
- :rack_test
Under the hood, PageMagic is using Capybara so you can register any Capybara compliant driver you want. See below for how to do this.
Note: We don't want to impose particular driver versions so PageMagic does not list any as dependencies. Therefore you will need add the requiste gems to your Gemfile.
Page mapping
With PageMagic you can map which pages should be used to handle which resources. Meaning that when a the page in the browser changes, PageMagic loads the correct PageObject class to handle it. This feature removes a lot of the juggling and brings back fluency to your code!
# define what pages map to what
session.define_page_mappings '/' => GitHub, '/search' => ResultsPage
You can use even use regular expressions and provide more than one mapping to the same page object class.
Note: By default mappings are matched against a URL's path. In addition, PageMagic supports mapping against both query string parameters and the fragement identifer (see below). Any combination of these can be used to define a page mapping.
Mapping against query string parameters
browser.define_page_mappings PageMagic.mapping(parameters: {parameter_name: string_or_regex}) => ResultsPage
Mapping against fragment identifiers
JavaScript MVC frameworks allow different resources to be mapped the fragment portion of URLs. That is the part of the URL that follows the Fragement identififer (#). PageMagic supports mapping page_objects against URL fragments.
browser.define_page_mappings PageMagic.mapping(fragment: string_or_regex) => ResultsPage
Loading pages/elements from source
PageMagic supports loading page objects using html source. This technique can be useful for getting quick feedback that your templates correctly render based on your view objects. I.e you can test your templates and partials/fragments in isolation.
class MyPage
include PageMagic
element(:link, id: 'link_id')
#element definitions
end
page_instance = Page.load(html_string)
page_instance.link.text # returns the link text
class CustomElement < PageMagic::Element
element(:link, id: 'link_id')
#element definitions
end
page_element = CustomElement.load(html_string)
page_element.link.text # returns the link text
Watchers
PageMagic lets you set a watcher on any element. Use watchers to decide when things have changed. The watch
method can be called from anywhere within an element definition. For PageObjects it can only be called from within hooks and helper methods.
Note: Watchers are not inherited
Method watchers
Method watchers watch the output of the given method name.
button :javascript_button, css: '.fancy_button' do
watch(:url)
after_events do
wait_until{changed?(:url)}
end
end
Simple watchers
Use watch
method passing two parameters, the first is the name of the element you want to keep
an eye on and the second is the method that needs to be called to get the value that should be observed.
element :product_row, css '.cta' do
watch(:total, :text)
after_events do
wait_until{changed?(:total)}
end
end
Custom watchers
Custom watchers are defined by passing a name and block parameter to the watch
method. The block returns the value
that needs to be observed. Use watch in this way if you need to do something non standard to obtain a value or to
access an element not located within the current element but elsewhere within the page.
element :product_row, css '.cta' do
watch(:total) do
session.nav.total.text
end
after_events do
wait_until{changed?(:total)}
end
end
Waiting
It's inevitable that if there is JavaScript on the page that you are going to have to wait for things to happen. PageMagic supplies the wait_until
method that can be used anywhere you might need it. The wait_until method takes a block that it will execute until either that block returns true or the timeout occurs. See the method docs for details on configuring timeouts and retry intervals.
Drivers
Registering a custom driver
You can register any Capybara compliant driver as follows
#1. Define driver, constructor to PageMagic::Driver takes a list of browser aliases.
# Selenium Webdriver for example supports driving more than one.
Webkit = PageMagic::Driver.new(:webkit) do |app, options, browser_alias_chosen|
# Write the code necessary to initialise the driver you have chosen
require 'capybara/webkit'
Capybara::Webkit::Driver.new(app,
)
end
#2. Register driver
PageMagic.drivers.register Webkit
#3. Use registered driver
session = PageMagic.session(browser: webkit, url: 'https://www.github.com')
Cucumber quick start
You can obviously use PageMagic anywhere you fancy but one of the places you might decide to use it is within a Cucumber test suite. If that's the case something like the following could prove useful.
Helper methods
Put the following in to features/support/page_magic.rb
to make these helpers available to all of your steps.
require 'page_magic'
require 'active_support/inflector'
require 'your_pages'
World(Module.new do
def page_class(string)
"#{string}Page".delete(' ').constantize
end
def snake_case(string)
string.delete(' ').underscore
end
def session
$session ||= begin
PageMagic.session(browser: :chrome, url: the_base_url).tap do |session|
session.define_page_mappings '/login' => LoginPage,
'/' => HomePage
end
end
end
end)
Example steps
Use the above helpers to navigate to pages with steps like the following.
Given /^I am on the '(.*)' page$/ do |page_name|
session.visit(page_class(page_name))
end
And /^I set '(.*)' to be '(.*)'$/ do |field, value|
session.send(snake_case(field)).set value
end
When /^I click '(.*)'$/ do |element|
session.send(snake_case(element)).click
end
Then /^I should be on the '(.*)' page$/ do |page_name|
current_page = session.current_page.class
expected_page = page_class(page_name)
fail "On #{current_page}, expected #{expected_page}" unless current_page == expected_page
end