Reading test data from Excel in Selenium Python - Build an Automation Script

Login test using data from Excel file

Preconditions (4)

Step 1: Open the Excel file 'testdata.xlsx'

Step 2: Read each row from the sheet 'LoginData'

Step 3: For each row, open the login page URL

Step 4: Enter the 'username' value into the username input field with id 'username'

Step 5: Enter the 'password' value into the password input field with id 'password'

Step 6: Click the login button with id 'loginBtn'

Step 7: Verify that the URL changes to 'https://example.com/dashboard' after login

Step 8: Log out or reset the state before next iteration

✅ Expected Result: For each username and password pair from Excel, the login succeeds and the dashboard page loads

Automation Requirements - Selenium with Python

Assertions Needed:

Verify URL after login is 'https://example.com/dashboard' for each data set

Best Practices:

Use openpyxl to read Excel data

Use explicit waits to wait for page load or elements

Use Page Object Model to separate page actions

Close browser after tests

Handle exceptions gracefully

Automated Solution

Selenium Python

import unittest
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
from openpyxl import load_workbook

class LoginPage:
    def __init__(self, driver):
        self.driver = driver
        self.username_input = (By.ID, 'username')
        self.password_input = (By.ID, 'password')
        self.login_button = (By.ID, 'loginBtn')

    def load(self):
        self.driver.get('https://example.com/login')

    def login(self, username, password):
        WebDriverWait(self.driver, 10).until(
            EC.visibility_of_element_located(self.username_input))
        self.driver.find_element(*self.username_input).clear()
        self.driver.find_element(*self.username_input).send_keys(username)
        self.driver.find_element(*self.password_input).clear()
        self.driver.find_element(*self.password_input).send_keys(password)
        self.driver.find_element(*self.login_button).click()

class TestLoginWithExcel(unittest.TestCase):
    @classmethod
    def setUpClass(cls):
        cls.driver = webdriver.Chrome()
        cls.driver.maximize_window()
        cls.wait = WebDriverWait(cls.driver, 10)

        # Load Excel workbook and sheet
        cls.workbook = load_workbook('testdata.xlsx')
        cls.sheet = cls.workbook['LoginData']

    def test_login_data_driven(self):
        login_page = LoginPage(self.driver)

        # Iterate over rows starting from row 2 (assuming row 1 is header)
        for row in self.sheet.iter_rows(min_row=2, values_only=True):
            username, password = row
            login_page.load()
            login_page.login(username, password)

            # Wait for URL to change to dashboard
            self.wait.until(EC.url_to_be('https://example.com/dashboard'))
            current_url = self.driver.current_url
            self.assertEqual(current_url, 'https://example.com/dashboard',
                             f'Login failed for user {username}')

            # For simplicity, navigate back to login page to reset state
            self.driver.get('https://example.com/login')

    @classmethod
    def tearDownClass(cls):
        cls.driver.quit()

if __name__ == '__main__':
    unittest.main()

This script uses unittest as the test framework and Selenium WebDriver to automate the browser.

The LoginPage class is a simple Page Object Model that encapsulates the login page elements and actions.

We use openpyxl to read the Excel file testdata.xlsx and get username and password pairs from the sheet LoginData.

In the test method, we loop through each row of data, open the login page, enter credentials, click login, and then wait explicitly for the URL to become the dashboard URL.

Assertions check that the URL is correct after login, indicating success.

After each login, we navigate back to the login page to reset the state for the next test data.

Finally, the browser is closed after all tests run.

This approach follows best practices: explicit waits, page objects, and clean test structure.

Common Mistakes - 5 Pitfalls

Hardcoding Excel file path without checking existence

Using time.sleep() instead of explicit waits

Not clearing input fields before sending keys

Not resetting state between test data iterations

Using absolute XPath for locating elements

Bonus Challenge

Now add data-driven testing with 3 different username and password pairs in the Excel file and verify all logins.

Show Hint

Practice

1. What is the main reason to read test data from an Excel file in Selenium Python tests?

easy

A. To create Excel files automatically

B. To make the test code run faster

C. To run tests with many different inputs easily

D. To avoid writing any test code

Solution

1. Step 1: Understand test data usage

   Test data from Excel allows running the same test with many inputs without changing code.

2. Step 2: Identify the benefit

   This makes tests flexible and easier to maintain.

3. Final Answer:

   To run tests with many different inputs easily -> Option C

4. Quick Check:

   Reading Excel data = flexible inputs [OK]

Hint: Excel stores many inputs for tests in one place [OK]

Common Mistakes:

• Thinking Excel makes tests faster
• Believing Excel replaces test code
• Confusing data reading with file creation

2. Which Python library is commonly used to read Excel files for Selenium tests?

easy

A. selenium

B. pandas

C. requests

D. openpyxl

Solution

1. Step 1: Recall Excel reading libraries

   openpyxl is a popular library to read/write Excel files in Python.

2. Step 2: Differentiate from other libraries

   pandas can read Excel but is heavier; requests is for web calls; selenium is for browser automation.

3. Final Answer:

   openpyxl -> Option D

4. Quick Check:

   Excel reading = openpyxl [OK]

Hint: openpyxl is made for Excel files in Python [OK]

Common Mistakes:

• Choosing selenium which automates browsers
• Picking requests which handles HTTP
• Confusing pandas with openpyxl

3. Given this code snippet, what will be printed?

from openpyxl import load_workbook
wb = load_workbook('data.xlsx')
sheet = wb.active
print(sheet['A2'].value)

Assuming cell A2 contains the text "TestUser".

medium

A. data.xlsx

B. TestUser

C. sheet['A2']

D. None

Solution

1. Step 1: Understand openpyxl cell access

   sheet['A2'].value reads the content of cell A2 in the active sheet.

2. Step 2: Check given cell content

   Cell A2 contains "TestUser", so print outputs this string.

3. Final Answer:

   TestUser -> Option B

4. Quick Check:

   sheet['A2'].value = "TestUser" [OK]

Hint: sheet['A2'].value reads cell A2 content [OK]

Common Mistakes:

• Printing the cell object instead of its value
• Confusing filename with cell content
• Expecting None if cell has text

4. What is wrong with this code snippet for reading Excel data?

from openpyxl import load_workbook
wb = load_workbook('testdata.xlsx')
sheet = wb['Sheet1']
for row in sheet.iter_rows(min_row=2, values_only=True):
    print(row[0])

medium

A. No error; code reads first column from second row correctly

B. Using sheet['Sheet1'] instead of wb['Sheet1']

C. Not specifying min_row=1 in iter_rows

D. Missing call to wb.save() before reading

Solution

1. Step 1: Check sheet access

   wb['Sheet1'] correctly accesses the sheet named 'Sheet1'.

2. Step 2: Analyze iter_rows usage

   iter_rows with min_row=2 and values_only=True returns tuples of cell values from second row onward.

3. Step 3: Confirm print statement

   Printing row[0] prints the first column value of each row starting from row 2.

4. Final Answer:

   No error; code reads first column from second row correctly -> Option A

5. Quick Check:

   Code reads data correctly [OK]

Hint: wb['Sheet1'] accesses sheet; iter_rows returns values [OK]

Common Mistakes:

• Using sheet['Sheet1'] instead of wb['Sheet1']
• Forgetting values_only=True to get cell values
• Thinking wb.save() is needed before reading

5. You want to read username and password pairs from Excel to run login tests. Which approach is best to handle empty cells safely?

hard

A. Use iter_rows with values_only=True and check if each cell is None before using

B. Skip checking cells and assume all data is present

C. Use sheet['A1'].value only and ignore other rows

D. Convert Excel file to CSV and read with open()

Solution

1. Step 1: Understand data safety

   Empty cells in Excel return None, which can cause errors if not checked.

2. Step 2: Use iter_rows with values_only=True and check for None

   This approach reads all rows and allows safe validation before using data in tests.

3. Step 3: Avoid unsafe assumptions

   Skipping checks or reading only one cell risks test failures or incomplete coverage.

4. Final Answer:

   Use iter_rows with values_only=True and check if each cell is None before using -> Option A

5. Quick Check:

   Check None in cells to avoid errors [OK]

Hint: Always check for None in Excel cell values [OK]

Common Mistakes:

• Ignoring empty cells causing test crashes
• Reading only one cell missing data
• Converting to CSV losing Excel features