sosodev/kinchan

Composable browser automation with Ruby

Kinchan

Composable browser automation with Ruby.

Requirements

• Ruby
• Bundler

Getting Started

Create a new directory for your Kinchan project

mkdir kinchan_project && cd kinchan_project

Create the tasks directory where you'll store your Kinchan tasks

mkdir tasks

Initialize bundler

bundle init

Add the Kinchan gem to your bundle

bundle add kinchan

Now that we've got the structure the rest of the readme will teach you how to create, compose, and run Kinchan tasks 👽

Creating a Task

In your tasks directory create a Ruby file with any name

e.g. touch ruby_reddit.rb

In your task's Ruby file you'll need to require 'kinchan'

and then define your task as a class that inherits from Kinchan::Task

so far your file should look a little something like this

require 'kinchan'

class VisitRubysReddit < Kinchan::Task
end

All Kinchan tasks require an execute method that takes a single parameter (the selenium browser object) like so

require 'kinchan'

class VisitRubyReddit < Kinchan::Task
  def execute(browser)
    browser.navigate.to 'https://old.reddit.com/r/ruby'
  end
end

That's all it takes to create a basic task! If we run it we'll see a browser process start and navigate to the Ruby subreddit. For a full description of the browser API check out the wiki page for Ruby Selenium (they call it a "driver").

Running a Task

Create a Ruby file in the root level of your Kinchan project and require your task

Create a new instance of the task and call run

e.g.

require_relative 'tasks/ruby_reddit'

VisitRubyReddit.new.run

That's all it takes to run a task. Kinchan handles the rest.

Passing Data to a Task

A task's initialize method can accept options, just don't forget to call super

e.g.

class Search < Kinchan::Task
  def initialize(**options)
    super
    @query = options[:query]
  end

  def execute(browser)
    browser.navigate.to 'https://www.google.com/search?q=#{CGI.escape(@query)}'
  end
end

Composing Tasks

Tasks can call any number of other tasks either before or after they execute, and their dependencies will have their dependencies ran and so on

This is done by specifying dependencies with a task's @before_tasks or @after_tasks in their initialize method

e.g.

class PrintFirstResult < Kinchan::Task
  def initialize(**options)
    super
    @before_tasks << { task: :search, options: options }
    # specify that the search task should run, with the same options, before running this task
  end

  def execute(browser)
    puts browser.execute_script "return document.querySelector('.srg a').innerText"
  end
end

Task's do not need to be in the same scope, as long as the task exists Kinchan will find and run it when appropriate

Examples

Setting Selenium Browser Options

before running your task you can modify the selenium browser options like so

Kinchan.browser = :chrome
Kinchan.browser_options = Selenium::WebDriver::Chrome::Options.new
Kinchan.browser_options.add_argument('--headless')