Selenium is an open source web testing tool that allows users to test web applications across different browsers and platforms. It includes a plethora of software that developers can use to automate web applications including IDE, RC, webdriver and Selenium grid, which all serve different purposes. Moreover, it serves the purpose of scraping dynamic web pages, something which Beautiful Soup can’t.
1.A Selenium Bindings in Python
Selenium Python bindings provide a simple API to write functional tests using it’s WebDriver. Through the API you can access all functionalities of Selenium WebDriver without hassle.
pip install Selenium
1.B Web Drivers
Selenium requires a web driver to interface and interact with the chosen browser, i.e. Chrome, Safari, Firefox, etc. A web driver is a package to set up interactivity with the user’s web browser. It interacts through a wire protocol which is common to all.
You can easily install the web drivers compatible with your browser. The following links will help you with that:
2.A Using Python Bindings
If you have installed Selenium Python bindings, you can start using it from Python like this:
from selenium import webdriver from selenium.webdriver.common.keys import Keys from time import sleep
The sleep module waits until the browser URL has completely loaded. Now we create a browser webdriver instance (here, Chrome) as follows:
driver=webdriver.Chrome("C:/chromedriver.exe") driver.get("https://www.covid19india.org/") sleep(2) //Waits for 2 seconds after navigating to the URL
The driver.get() method navigates to the page given by the URL and subsequently the chromedriver waits until the page has been fully loaded before returning control to the script.
2.B Web Scraping
There are various strategies to locate elements in a page. In this case, we use the find_element_by_xpath() method to navigate to the desired HTML-rendered values on https://www.covid19india.org/. The above script extracts seven different values from the desired URL, namely:
- Total Cases
- Total Active Cases
- Total Recovered Cases
- Total Deaths
- New Positive Cases
- New Recovered Cases
- Additional Deaths yet
These extracted values of COVID-19 statistics are displayed on the user’s console in real-time using Python using the print() statement as follows:
def extractor(): TCases = driver.find_element_by_xpath("/html/body/div/div/div/div/div/div/h1/span") TActive = driver.find_element_by_xpath("/html/body/div/div/div/div/div/div/h1/span") TRecov = driver.find_element_by_xpath("/html/body/div/div/div/div/div/div/h1/span") TDeath = driver.find_element_by_xpath("/html/body/div/div/div/div/div/div/h1/span") New_Cases = driver.find_element_by_xpath("/html/body/div/div/div/div/div/div/h4/span") New_Rcov = driver.find_element_by_xpath("/html/body/div/div/div/div/div/div/h4/span") New_Death = driver.find_element_by_xpath("/html/body/div/div/div/div/div/div/h4/span") print("Total Cases:", TCases.text) print("Total Active Cases:", TActive.text) print("Total Recovered Cases:", TRecov.text) print("Total Deaths:", TDeath.text) print("New Cases:", New_Cases.text[1:len(New_Cases.text)-1]) print("New Recovered Cases:", New_Rcov.text[1:len(New_Rcov.text)-1]) print("Additional Deaths yet:", New_Death.text[1:len(New_Death.text)-1])
The entire script can be automated to execute after a given interval using the sleep() module as follows:
while True: extractor() sleep(60*60) // The loop executes after every hour in this case
The while loop executes indefinitely and runs the extractor() function after every hour.
Here’s the entire web scraping program:
The output of the above program on the user’s console is as follows:
Total Cases: 2, 17, 187 Total Active Cases: 1, 07, 017 Total Recovered Cases: 1, 04, 071 Total Deaths: 6, 088 New Cases: +2561 New Recovered Cases: +543 Additional Deaths yet: +23 //The above COVID-19 values differ with time. Your output may differ.
The above script thus automates web scraping using Selenium and prints the updated statistics on the user’s console on an hourly basis.
Using this you can create a custom automated script for every single website which automates all your actions. Honestly, there’s no limit to web scraping and automation and the above is just an example to get you going.
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