ruby - How to specify the location of the chromedriver binary

Question

Earlier I had put the Chrome binary, "chromedriver.exe", in the "C:/Windows" directory and Watir was picking it from there. Now I have to move my project to another machine so I can't hardcode the executable path. I also want the binary to be kept with our code on Git rather than making each test engineer manually update the binary as newer versions are released.

Now I have placed Chrome binary at a absolute path, but it is not being found. Here is what I tried (hooks.rb):

  Before do
    puts "inside hooks in before"
    profile = Selenium::WebDriver::Chrome::Profile.new
    profile['download.prompt_for_download'] = false
    profile['download.default_directory'] = File.join(File.absolute_path('../..', File.dirname(__FILE__)),"browsers/chromedriver.exe")
    @browser = Watir::Browser.new :chrome, :profile => profile
  end

The output is:

inside hooks in before

Selenium::WebDriver::Error::WebDriverError: Unable to find the chromedriver executable. Please download the server from http://chromedriver.storage.googleapis.com/index.html and place it somewhere on your PATH. More info at http://code.google.com/p/selenium/wiki/ChromeDriver.
C:/Ruby193/lib/ruby/gems/1.9.1/gems/selenium-webdriver-2.44.0/lib/selenium/webdriver/chrome/service.rb:21:in `executable_path'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/selenium-webdriver-2.44.0/lib/selenium/webdriver/chrome/service.rb:34:in `default_service'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/selenium-webdriver-2.44.0/lib/selenium/webdriver/chrome/bridge.rb:14:in `initialize'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/selenium-webdriver-2.44.0/lib/selenium/webdriver/common/driver.rb:37:in `new'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/selenium-webdriver-2.44.0/lib/selenium/webdriver/common/driver.rb:37:in `for'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/selenium-webdriver-2.44.0/lib/selenium/webdriver.rb:67:in `for'
C:/Ruby193/lib/ruby/gems/1.9.1/gems/watir-webdriver-0.6.11/lib/watir-webdriver/browser.rb:46:in `initialize'
C:/Users/Admin/watircukepractice/test_puppies/features/support/hooks.rb:11:in `new'
C:/Users/Admin/watircukepractice/test_puppies/features/support/hooks.rb:11:in `Before'

I am on Windows 7, Using Ruby version 1.9.3p551 and I am referring to tutorial http://watirwebdriver.com/chrome/.

How do I tell Watir (and Selenium-WebDriver) the location of the chromedriver.exe?

Answer 1

Solution 1 - Selenium::WebDriver::Chrome.driver_path=

There is a Selenium::WebDriver::Chrome.driver_path= method that allows specifying of the chromedriver binary:

require 'watir'

# Specify the driver path
chromedriver_path = File.join(File.absolute_path('../..', File.dirname(__FILE__)),"browsers","chromedriver.exe")
Selenium::WebDriver::Chrome.driver_path = chromedriver_path

# Start the browser as normal
b = Watir::Browser.new :chrome
b.goto 'www.google.com'
b.close

Solution 2 - Specify :driver_path during browser initialization

As an alternative, you can also specify the driver path when initializing the browser. This is a bit nicer in that you do not need to have Selenium code, but would be repetitive if you initialize the browser in different places.

# Determine the driver path
chromedriver_path = File.join(File.absolute_path('../..', File.dirname(__FILE__)),"browsers","chromedriver.exe")

# Initialize the browser with the driver path
browser = Watir::Browser.new :chrome, driver_path: chromedriver_path

Solution 3 - Update ENV['PATH']

When I had originally answered this question, for whatever reason, I had not been able to get the above solution to work. Setting the value did not appear to be used when Selenium-WebDriver started the driver in. While the first solution is the recommended approach, this is an alternative.

Another option is to programmatically add the desired directory to the path, which is stored in the ENV['PATH']. You can see in the Selenium::WebDriver::Platform that the binary is located by checking if the executable exists in any of the folders in the path (from version 2.44.0):

def find_binary(*binary_names)
  paths = ENV['PATH'].split(File::PATH_SEPARATOR)
  binary_names.map! { |n| "#{n}.exe" } if windows?

  binary_names.each do |binary_name|
    paths.each do |path|
      exe = File.join(path, binary_name)
      return exe if File.executable?(exe)
    end
  end

  nil
end

To specify the folder that includes the binary, you simply need to change the ENV['PATH'] (to append the directory):

require 'watir'

# Determine the directory containing chromedriver.exe
chromedriver_directory = File.join(File.absolute_path('../..', File.dirname(__FILE__)),"browsers")

# Add that directory to the path
ENV['PATH'] = "#{ENV['PATH']}#{File::PATH_SEPARATOR}#{chromedriver_directory}"

# Start the browser as normal
b = Watir::Browser.new :chrome
b.goto 'www.google.com'
b.close