file_detector error watir webdriver - ruby

Question

I need to upload file through file field form. Locally it works fine. But through Selenium Grid test need to upload file to remote machine.
The solution is using file detector. As described here https://github.com/watir/watir-webdriver/issues/175 or here https://saucelabs.com/resources/selenium-file-upload
In my hooks.rb
require "watir-webdriver"
client = Selenium::WebDriver::Remote::Http::Default.new
capabilities = Selenium::WebDriver::Remote::Capabilities.new(browser_name: ENV['BROWSER'].to_sym, :http_client => client)
browser = if ENV['REMOTE']
Watir::Browser.new(
:remote,
url: 'http://remoteurl:4444/wd/hub',
desired_capabilities: capabilities,
:http_client => client
)
else
Watir::Browser.new(ENV['BROWSER'].to_sym, :http_client => client)
end
browser.driver.file_detector = lambda do |args|
str = args.first.to_s
str if File.exist?(str)
end
But when I run tests they end up with error:
undefined method `file_detector=' for #<Selenium::WebDriver::Driver:0x000000012902b0> (NoMethodError)
How can I upload file via Selenium Grid?

Answer 1

Looking through the code, the file_detector= method is defined in the Selenium::WebDriver::DriverExtensions::UploadFiles module. The only bridge that uses this driver extension is the Selenium::WebDriver::Remote::Bridge class.
In other words, the method will only be available to browsers created using the :remote type:
browser = Watir::Browser.new(:remote)
I assume your are getting this exception when using non-remote drivers (ie when going down the "else" part of the "if" statement). Try moving the setting of the file_detector to only be when using a remote driver.
if ENV['REMOTE']
browser = Watir::Browser.new(
:remote,
url: 'http://remoteurl:4444/wd/hub',
desired_capabilities: capabilities,
:http_client => client
)
browser.driver.file_detector = lambda do |args|
str = args.first.to_s
str if File.exist?(str)
end
else
browser = Watir::Browser.new(ENV['BROWSER'].to_sym, :http_client => client)
end