08. Selenium | External data sources for DDT

01. Intro

It is a good idea to separate the test data from the code and put it in an external source for easy maintenance and avoid changes to the test code each time you want to update the values.

 

02. Reading values from CSV

Firstly, we make a CSV file for testing.

Create get_data() method: This accepts the path and name of the CSV file.

This method uses the CSV library to read the values from the file and returns a list of these values.

import csv

def get_data(file_name):
    # create an empty list to store rows
    rows = []
    
    # open the CSV file
    data_file = open(file_name, "rt")
    
    # create a CSV Reader from CSV file
    reader = csv.reader(data_file)
    
    # skip the header
    next(reader, None)
    
    # add rows from reader to list
    for row in reader:
    	rows.append(row)
    return rows

 

03. Test Code

    # get the data from csv file
    @data(*get_data("D://selenium//DataDrivenTest//testdata.txt"))
    @unpack
    def test_search(self, search_value, expected_count):
        # get the search textbox
        search_field = self.driver.find_element(By.NAME, 'q')
        search_field.clear()

        # enter search keyword and submit
        # use search_value argument to pass data
        search_field.send_keys(search_value)
        search_field.submit()

        # get all the anchor elements which have product names
        products = self.driver.find_elements(By.XPATH, "//h2[@class='product-name']/a")

        expected_count = int(expected_count)
        if expected_count > 0:
            self.assertEqual(expected_count, len(products))
        else:
            msg = self.driver.find_element(By.CLASS_NAME, 'note-msg')
            self.assertEqual("Your search returns no results.", msg.text)

 

04. Reading values from Excel

we make an Excel file for testing.

 Reading value from the Excel spreadsheet will need another library called xlrd

pip install xlrd==1.2.0

def get_data(file_name):
    # create an empty list to store rows
    rows = []
    # open the excel file
    book = xlrd.open_workbook(file_name)
    # get the first sheet
    sheet = book.sheet_by_index(0)
    # iterate through the sheet and get data
    for row_idx in range(1, sheet.nrows):
        rows.append(list(sheet.row_values(row_idx, 0, sheet.ncols)))
    return rows

 

05. Test Code

# get the data from csv file
    @data(*get_data("D://selenium//DataDrivenTest//testdata.xlsx"))
    @unpack
    def test_search(self, search_value, expected_count):
        # get the search textbox
        search_field = self.driver.find_element(By.NAME, 'q')
        search_field.clear()

        # enter search keyword and submit
        # use search_value argument to pass data
        search_field.send_keys(search_value)
        search_field.submit()

        # get all the anchor elements which have product names
        products = self.driver.find_elements(By.XPATH, "//h2[@class='product-name']/a")

        expected_count = int(expected_count)
        if expected_count > 0:
            self.assertEqual(expected_count, len(products))
        else:
            msg = self.driver.find_element(By.CLASS_NAME, 'note-msg')
            self.assertEqual("Your search returns no results.", msg.text)

 

Reference: Learning Selenium Testing Tools with Python by Unmesh Gundecha