In this recipe, we will create and execute tests in parallel with Python bindings using the subprocess module. We will use the Hub and nodes configured in earlier recipes to run these tests.
We will create two test scripts to test the application with Firefox and Internet Explorer using the following steps. You can also create a single test and parameterize it similar to what we did for TestNG:
- For the first Python test, which will test the application functionality using the Firefox browser, name this test as
test_on_firefox.pyand copy the following code:import unittest from selenium import webdriver from selenium.webdriver.common.desired_capabilities import DesiredCapabilities from selenium.webdriver.support.ui import WebDriverWait class OnFirefox(unittest.TestCase): def setUp(self): self.driver = webdriver.Remote( command_executor='http://localhost:4444/wd/hub',desired_capabilities=DesiredCapabilities.FIREFOX) def test_gogle_search_ie(self): driver = self.driver driver.get("http://www.google.com") inputElement = driver.find_element_by_name("q") inputElement.send_keys("Cheese!") inputElement.submit() WebDriverWait(driver, 20).until(lambda driver: driver.title.lower().startswith("cheese!")) self.assertEqual("cheese! - Google Search", driver.title) def tearDown(self): self.driver.quit() if __name__ == "__main__": unittest.main(verbosity=2) - For the second Python test, which will test the application functionality using the Internet Explorer browser, name this test as
test_on_ie.pyand copy the following code:import unittest from selenium import webdriver from selenium.webdriver.common.desired_capabilities import DesiredCapabilities from selenium.webdriver.support.ui import WebDriverWait class OnFirefox(unittest.TestCase): def setUp(self): self.driver = webdriver.Remote(command_executor='http://localhost:4444/wd/hub',desired_capabilities=DesiredCapabilities.INTERNETEXPLORER) def test_google_search_ff(self): driver = self.driver driver.get("http://www.google.com") inputElement = driver.find_element_by_name("q") inputElement.send_keys("Cheese!") inputElement.submit() WebDriverWait(driver, 20).until(lambda driver: driver.title.lower().startswith("cheese!")) self.assertEqual("cheese! - Google Search", driver.title) def tearDown(self): self.driver.quit() if __name__ == "__main__": unittest.main(verbosity=2) - Finally, we need to create a Python script, which will use the
subprocessmodule to run these tests concurrently on different nodes. Name this script asrunner.pyand copy the following code:import glob from subprocess import Popen tests = glob.glob('test*.py') processes = [Popen('python %s' % test, shell=True) for test in tests] for process in processes: process.wait()
We need to place all three scripts in the same directory. When we execute runner.py, it collects all the tests with names starting with test using the glob function. Then we append each test using the Popen function from the subprocess module. The Popen() function calls each test using Python as a subprocess of the main process and waits for the script to complete.
We can also use the nose module for Python to run the tests in parallel. First, we need to install the nose unit testing framework using the following command:
pip nose
After the nose module is installed, you need to open the folder where all the tests are stored and use the following command:
nosetests --processes=2
This will call the nosetests scripts, which will locate all the files with a test prefix in the current directory and start running tests concurrently. In this example we are running two tests, so we need to specify the value for processes argumented as 2. The nose module internally uses a multiprocessing module for concurrent execution.