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Your Python Selenium tests should be written in a manner to conform to pytest standards

The initial code you were given was a sample piece of the code showing you the Selenium capabilities. But in order to use Selenium in a testing environment, you will need to structure your code as follows

  1. Each file containing the tests should follow one of the these formats

    1. test_<file_name>.py

    2. <file_name>_test.py

  2. The file should comprise of tests. Tests follow the standard as defined by pytest, see this link https://docs.pytest.org/en/reorganize-docs/new-docs/user/assert_statements.html

    1. A test method should begin test_<method_name>()

We originally supplied you with the following piece of code

import time
from selenium import webdriver
from selenium.webdriver.common.alert import Alert

driver = webdriver.Chrome('c:\\pf\\bin\\chromedriver.exe')  
# Optional argument, if not specified will search path.
#driver = webdriver.Chrome()
driver.get('file://C:/work/git/nodejs-sky/selenium-setup/simple_page.html')
input_field = driver.find_element_by_id("message")
input_field.send_keys("help me!")
submitBtn = driver.find_element_by_id("submit-button")
time.sleep(2) # Let the user actually see something!

submitBtn.click()
time.sleep(3)

alert = Alert(driver)
alert.accept()
time.sleep(3)

driver.get('http://www.google.com/')
time.sleep(5) # Let the user actually see something!

search_box = driver.find_element_by_name('q')
search_box.send_keys('ChromeDriver')
search_box.submit()
time.sleep(5) # Let the user actually see something!

driver.quit()

Let’s clean it up

import time
from selenium import webdriver
from selenium.webdriver.common.alert import Alert

driver = object

def setup():
    global driver

    driver = webdriver.Chrome('c:\\pf\\bin\\chromedriver.exe')  
    # Optional argument, if not specified will search path.
    #driver = webdriver.Chrome()

def test_some_functionality():
    setup()

    driver.get('file://C:/work/git/nodejs-sky/selenium-setup/simple_page.html')
    input_field = driver.find_element_by_id("message")
    input_field.send_keys("help me!")
    submitBtn = driver.find_element_by_id("submit-button")
    time.sleep(2) # Let the user actually see something!

    submitBtn.click()
    time.sleep(3)

    alert = Alert(driver)
    alert.accept()
    time.sleep(3)

    driver.get('http://www.google.com/')
    time.sleep(5) # Let the user actually see something!

    search_box = driver.find_element_by_name('q')
    search_box.send_keys('ChromeDriver')
    search_box.submit()
    time.sleep(5) # Let the user actually see something!

    driver.quit()

    assert True
    
test_some_functionality()

Notice we put any intialisation code in something called setup(). This is so we can reuse this code across multiple tests.

To run the above code use the following command

pytest <file_name>.py

We then place the rest of the code in a method called test_some)functionality(). we could have split this up further into two separate tests as shown here

import time
from selenium import webdriver
from selenium.webdriver.common.alert import Alert

driver = object


def setup_module():     # this method is called once before any tests run
    global driver

    driver = webdriver.Chrome('c:\\pf\\bin\\chromedriver.exe')  
    # Optional argument, if not specified will search path.
    #driver = webdriver.Chrome()

def teardown_module():  # this method is called once after all tests have run
    driver.close()
    driver.quit()

def test_fields_on_form():
    driver.get('file://C:/work/git/nodejs-sky/selenium-setup/simple_page.html')
    input_field = driver.find_element_by_id("message")
    input_field.send_keys("help me!")
    submitBtn = driver.find_element_by_id("submit-button")
    time.sleep(2) # Let the user actually see something!

    submitBtn.click()
    time.sleep(3)

    alert = Alert(driver)
    alert.accept()
    time.sleep(3)

    assert True

def test_navigation():
    driver.get('http://www.google.com/')
    time.sleep(5) # Let the user actually see something!

    search_box = driver.find_element_by_name('q')
    search_box.send_keys('ChromeDriver')
    search_box.submit()
    time.sleep(5) # Let the user actually see something!

    assert True

Notice how we have cleaned up the code.

If we put this code in a file called test_demo_selenium.py. It could be executed by simply typing pytest

Breakdown of Selenium API

Selenium Python Basics

Locating Elements

Action Chains

Waiting for HTTP Requests

Selenium so quick, things fail lol

You may be getting an interesting error when you try to use an element on a page, such as reading a value from it or clicking on it. This is because when you try to invoke the action, the page hasn’t fully loaded the elements into the DOM. Use the following code courtesy of Gregor to get around the problem

from selenium.webdriver.support.ui import WebDriverWait

element_id = object

def find_the_element_by_id(driver):
    element = driver.find_element_by_id(element_id)
    if element:
        return element
    else:
        return False

def function_where_test_written():
    global element_id
    
    element_id = "qa"
    qa = WebDriverWait(driver, 1).until(find_the_element_by_id)
    qa.click()

Code explained

Line 1 : set up a variable that we can pass the id or whatever the search criteria is into

Line 3-8 : create a function that does the query on the DOM using the webdriver that is passed in

Line 15 : specify the thing that you want search for

Line 16 : use a special API call WebDriverWait() that tells the webdriver (the first parameter being passed in) to wait for a certain period (the second parameter, in this example up to 1 second) until calling your query function “find_the_element_by_id” - this is passed into the until() method. Essentially it causes the WebDriver to slow down until the DOM is stable (in other words the page has been properly loaded).

Line 17 : perform your action on the element as normal

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