# Selenium Python tutorial

Applitools SDKs work with existing test frameworks to take screenshots of pages, elements, regions or iframes and upload them along with DOM snapshots to our Eyes server. Our AI then compares them with previous test executions' screenshots (aka Baselines) and reports if there is a bug or not. It's that simple!

# 1.1 Baseline vs. Checkpoint images

When you first run the test, our A.I. server stores those first set of screenshots as Baseline images. When you run the same test again (and everytime there after), the A.I. server compares the new set of screenshots, aka Checkpoint images, with the corresponding Baseline images and highlights differences in a pink color.

# 1.2 Marking the test as "Pass" or "Fail"

When the AI compares the baseline and the checkpoint image, if it finds a legitimate difference, it will mark the test as Unresolved. This is because the AI doesn't know if the difference is because of a new feature or a real bug and will wait for you to manually mark it as a Pass/Fail for the 1st time.

If you mark the Unresolved checkpoint image as "Failed", it'll only mark the current test result as Failed.

If you mark the Unresolved checkpoint image as a "Pass", then it means that the difference is due to a new feature so we set the new checkpoint image as the new baseline and mark the current test as Pass. Going forward we'll compare any future tests with this new baseline.

# A powerful test results dashboard

We provide a state-of-the-art dashboard that makes it very easy for you to analyze differences, report bugs and much more. For more information on the Applitools dashboard check out these articles.

The following Gifs show various tools Applitools provides to easily analyze various differences

# Highlight differences between the baseline and checkpoint

# Zoom into differences

# Toggle between baseline and checkpoint

# Show both the baseline and checkpoint side-by-side

You can select a section of the image and directly file a bug in Jira or Github. No need to manually take screenshots, write steps and explain things! To read more about bug regions check out this article.

1. Create a free Applitools account and get the Applitools API KEY

2. Please set the APPLITOOLS_API_KEY environment variable

   • Mac: export APPLITOOLS_API_KEY='YOUR_API_KEY'

   • Windows: set APPLITOOLS_API_KEY='YOUR_API_KEY'

   TIP

   1. You may skip this step if you want to hard code the API KEY inside the tutorial project's code.
   2. It's better to store APPLITOOLS_API_KEY in the system variables (in Windows) or in the ~/.bash_profile (in Mac) so that it is accessible from all Terminal shells

3. Install Python 3. This is a good resource

4. Install git from https://git-scm.com​

   TIP

   Installing git is optional. You need this mainly to clone the demo project from the Github repository. Instead of installing git, you can simply download the Zip file from the repo. Further, If you are Mac, you already have git.

5. Install Google Chrome browser from https://www.google.com/chrome/

6. Install ChromeDriver on your machine and make sure it's is in the PATH.

Below are some resources from the internet that'll help you

• Install on Mac
• Install on windows

Tip: On Mac, place the chromedriver executable in /usr/local/bin folder so Eclipse and IntelliJ can find it.

There are two main ways in which you can run tests.

The Applitools Ultrafast Grid (option 1) Test across all browsers and viewports 30-70 times faster than traditional test clouds. Using this approach, your tests will execute on a local browser once with the DOM, CSS, and additional artifacts captured by the SDK and sent to the Ultrafast Grid for parallel rendering and Visual AI comparison. This is the preferred execution method, however please note that it is a premium feature.

The second approach is to Run Local (option 2). This is the classic test execution in which your tests execute locally and each call to eyes via the SDK will send a screenshot to Eyes for Visual AI comparison.

While running tests using the classic approach is a great start - we recommend running tests on the Ultrafast Grid, the fastest way to ensure quality and consistency across all browsers, viewports, and devices.

# 1. Introduction To the Ultrafast Grid

In real world testing, you'll need to test your app on multiple browsers, viewports and mobile devices. So you'll need to run and re-run ALL the tests in different browsers and multiple viewports to ensure things are fine - which could take hours and hours to complete. You may also encounter browsers not opening properly, or hanging and what not.

What if you could run in just one browser, just once, and still do cross-browser tests across various browsers, viewports and multiple mobile emulators? That's where Ultrafast Grid comes in.

# 2. What Is The Ultrafast Grid?

The Ultrafast Grid provides an elegant and an ultra fast way to render pages in different browsers, viewports and mobile simulators and then take screenshots and then send those screenshots to Applitools AI server. With Ultrafast Grid you just need to run your test in a single browser but perform end-to-end and cross-browser tests in various browsers such as Chrome,Firefox, IE, and also numerous combinations of viewports and in mobile simulators -- all in under a minute. Without Ultrafast Grid, you'll be wasting a lot of time and money running those tests in multiple browsers which could take hours and are error-prone.

And since Ultrafast Grid is integrated with our Eyes AI, you'll actually find a lot more functional and visual bugs than you'd normally find.

Further, you can use our Root-Cause-Analysis (RCA) feature to figure out exactly which DOM element or CSS caused difference! So you can go backwards, from the screenshot to the code!

Best part: All you need to do is to simply make eyes.check calls in your existing Selenium tests after adding our SDK and instantiating Ultrafast Grid. And that's all there is to it!

# How it works

Once you add and instantiate the Applitools SDK, simply add eyes.check calls wherever you want to check if the state of the page looks OK. Then run the Selenium test as usual. And while running the tests, anytime it encounters eyes.check (or similar methods), Applitools SDK uploads the DOM resource of that page to our Ultrafast Grid behind the scenes and in batches. The Ultrafast Grid then renders every page in different browsers and mobile emulators (in parallel) and takes screenshots as per the configuration you set. Finally, it sends those screenshots to our AI Server.

When you first run the test, our AI server simply stores those 1st set of screenshots as Baseline images. When you run the same test again, the AI server will compare the new set of screenshots, aka Checkpoint images, with the corresponding Baseline images and highlights bugs.

# 3. Getting Started With The Ultrafast Grid

# Pre-requisites:

1. Python 3 is installed on your machine. Install Python 3.
2. Package manager pip is installed on your machine. Install pip
3. Chrome browser is installed on your machine. Install Chrome browser
4. Chrome Webdriver is on your machine and is in the environment variable PATH. Here are some resources from the internet that'll help you.
   • Download Chrome Webdriver, Read the docs, Stackoverflow, Youtube
5. Git is installed on your machine. Install git
6. If you want to run example from IDE, install any IDE for Python (e.g. PyCharm )

# Run the example

Start with the ready-to-run code Github repo

1. Git clone this repo git clone https://github.com/applitools/tutorial-selenium-python-ultrafastgrid.git, or download this as a Zip file and unzip it
2. cd tutorial-selenium-python-ultrafastgrid
3. Open in any editor file ultrafastgrid_demo.py and set your ApiKey in string .set_api_key('...')
4. Install requirements pip install -r requirements.txt
5. Run ultrafastgrid_demo.py by calling python ultrafastgrid_demo.py
6. If you want run from IDE - start PyCharm, open just cloned project, set project interpreter by File > Settings > Project: > Project Interpreter choose interpreter by dropdown box; tap Run and choose ultrafastgrid_demo.

# Sample code

from webdriver_manager.chrome import ChromeDriverManager
from selenium.webdriver import Chrome
import os


from applitools.selenium import (
    logger,
    VisualGridRunner,
    Eyes,
    Target,
    BatchInfo,
    BrowserType,
    DeviceName,
)


def set_up(eyes):

    # You can get your api key from the Applitools dashboard
    eyes.configure.set_api_key("APPLITOOLS_API_KEY")

    # create a new batch info instance and set it to the configuration
    eyes.configure.set_batch(BatchInfo("Ultrafast Batch"))

    # Add browsers with different viewports
    # Add mobile emulation devices in Portrait mode
    (
        eyes.configure.add_browser(800, 600, BrowserType.CHROME)
        .add_browser(700, 500, BrowserType.FIREFOX)
        .add_browser(1600, 1200, BrowserType.IE_11)
        .add_browser(1024, 768, BrowserType.EDGE_CHROMIUM)
        .add_browser(800, 600, BrowserType.SAFARI)
        .add_device_emulation(DeviceName.iPhone_X)
        .add_device_emulation(DeviceName.Pixel_2)
    )


def ultra_fast_test(web_driver, eyes):
    try:
        # Navigate to the url we want to test
        web_driver.get("https://demo.applitools.com")

        # Call Open on eyes to initialize a test session
        eyes.open(
            web_driver, "Demo App", "Ultrafast grid demo", {"width": 800, "height": 600}
        )

        # check the login page with fluent api, see more info here
        # https://applitools.com/docs/topics/sdk/the-eyes-sdk-check-fluent-api.html
        eyes.check("", Target.window().fully().with_name("Login page"))

        web_driver.find_element_by_id("log-in").click()

        # Check the app page
        eyes.check("", Target.window().fully().with_name("App page"))

        # Call Close on eyes to let the server know it should display the results
        eyes.close_async()
    except Exception as e:
        eyes.abort_async()
        print(e)


def tear_down(web_driver, runner):
    # Close the browser
    web_driver.quit()

    # we pass false to this method to suppress the exception that is thrown if we
    # find visual differences
    all_test_results = runner.get_all_test_results(False)
    print(all_test_results)


# Create a new chrome web driver
web_driver = Chrome(ChromeDriverManager().install())

# Create a runner with concurrency of 1
runner = VisualGridRunner(1)

# Create Eyes object with the runner, meaning it'll be a Visual Grid eyes.
eyes = Eyes(runner)

set_up(eyes)

try:
    # ⭐️ Note to see visual bugs, run the test using the above URL for the 1st run.
    # but then change the above URL to https://demo.applitools.com/index_v2.html
    # (for the 2nd run)
    ultra_fast_test(web_driver, eyes)
finally:
    tear_down(web_driver, runner)

# Run the demo app

1. Get the code:
   • Option 1: git clone https://github.com/applitools/tutorial-selenium-python.git
   • Option 2: Download it as a Zip file and unzip it.
2. cd tutorial-selenium-python folder
3. Note: Remember to set the APPLITOOLS_API_KEY env variable.
4. pip3 install eyes-selenium
5. python3 tutorial.py
6. After you run one set of tests, you now have the baseline. Run the same test but with this URL: https://demo.applitools.com/index_v2.html. This version of the demo app has some visual bugs so you can see how it all works. And the second set of screenshots are called "Checkpoint images".

# Sample test

import os
import pytest

from selenium import webdriver
from applitools.selenium import Eyes, Target, BatchInfo, ClassicRunner
from webdriver_manager.chrome import ChromeDriverManager


@pytest.fixture(scope="module")
def batch_info():
    """
    Use one BatchInfo for all tests inside module
    """
    return BatchInfo("Some general Test cases name")


@pytest.fixture(name="driver", scope="function")
def driver_setup():
    """
    New browser instance per test and quite.
    """
    driver = webdriver.Chrome(ChromeDriverManager().install())
    yield driver
    # Close the browser.
    driver.quit()


@pytest.fixture(name="runner", scope="session")
def runner_setup():
    """
    One test runner for all tests. Print test results in the end of execution.
    """
    runner = ClassicRunner()
    yield runner
    all_test_results = runner.get_all_test_results()
    print(all_test_results)


@pytest.fixture(name="eyes", scope="function")
def eyes_setup(runner, batch_info):
    """
    Basic Eyes setup. It'll abort test if wasn't closed properly.
    """
    eyes = Eyes(runner)
    # Initialize the eyes SDK and set your private API key.
    eyes.api_key = os.environ["APPLITOOLS_API_KEY"]
    eyes.configure.batch = batch_info
    yield eyes
    # If the test was aborted before eyes.close was called, ends the test as aborted.
    eyes.abort_if_not_closed()


def test_tutorial(eyes, driver):
    # Start the test and set the browser's viewport size to 800x600.
    eyes.open(driver, "Test app", "First test", {"width": 800, "height": 600})
    # Navigate the browser to the "hello world!" web-site.
    driver.get("https://demo.applitools.com")

    # Visual checkpoint #1.
    eyes.check("Login Window test", Target.window())

    # End the test.
    eyes.close(False)

1. Forgetting to set your API key (or getting 401 exception).

   • Resolution: See here and here

2. Applitools is not opening the app (appears to crash).

   • In order to make sure the screenshots are consistent across different tests runs. Applitools uses Viewport as an input. A viewport is simply the size of the screenshot you are taking (width and height). Applitools tries to resize the browser to that size before taking the screenshot. If you are running the app on a small laptop and/or have set the Viewport much larger than the laptop’s screen, then you’ll see this error.
   • Solution: Reduce the height or the width. For more see here.

3. Not properly loading the API key from the environment variable into your IDE (like Eclipse).

   • After setting the APPLITOOLS_API_KEY in the environment variable to hold your Applitools API key, open the IDE from the command line terminal (and not from the IDE directly). On Mac, it’d look like this: Open a Terminal and then type: open ~/Applications/Eclipse.app. This will load Eclipse with all the environment variables.

4. Trying to run the test but nothing happens

   • Check if you the APPLITOOLS_API_KEY is null

5. Incompatibility between Chrome browser and Chrome driver.

   • Make sure for your version of Google Chrome, you are using the corresponding Chrome driver

6. Debug logs

   • See this article to enable debug logs to help file support ticket