In this post, we'll walk through a Python script that uses Selenium to automate scrolling through a web page. This can be particularly useful for scraping content from websites with infinite scrolling, like social media feeds or news sites.
Why Automate Scrolling?
Websites with infinite scrolling load more content as you scroll down the page. To scrape data from such sites, you need to keep scrolling to load all the available content. Manually doing this is tedious, so automating the process with Selenium can save time and effort.
The Script
Here’s a breakdown of our script:
1. Importing Required Libraries
First, we import the necessary libraries. Selenium helps us control the web browser, and the time and datetime libraries allow us to manage wait times and log timestamps.
from selenium import webdriver from selenium.webdriver.common.by import By from selenium.webdriver.common.keys import Keys from selenium.webdriver.support.ui import WebDriverWait from selenium.webdriver.support import expected_conditions as EC from selenium.common.exceptions import TimeoutException import time import datetime |
2. Logging Function
The log function helps us log messages with the current time. This is useful for debugging and tracking the script’s progress.
def log(text):
"""
Logs a message with the current time.
"""
now = datetime.datetime.now()
current_time = now.strftime("%H:%M:%S")
print(f"[LOG {current_time}] {text}")
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3. Scrolling Function
The scroll_page function takes a Selenium WebDriver instance and scrolls the web page. It scrolls a maximum number of times (max_scroll_count) or until no new content is loaded.
def scroll_page(driver, max_scroll_count=5, scroll_pause_time=5):
"""
Scrolls the webpage using the provided WebDriver instance.
Args:
driver (webdriver): The WebDriver instance to use for scrolling.
max_scroll_count (int): The maximum number of times to scroll the page.
scroll_pause_time (int): The time to wait after each scroll.
Returns:
bool: False if the bottom of the page is reached or the max scroll count is exceeded.
"""
scroll_count = 1
last_height = driver.execute_script("return document.body.scrollHeight")
while scroll_count <= max_scroll_count:
# Scroll down to the bottom of the page
driver.execute_script("window.scrollTo(0, document.body.scrollHeight);")
# Wait to load the page
time.sleep(scroll_pause_time)
log(f"Scroll count={scroll_count}")
# Calculate new scroll height and compare with last scroll height
new_height = driver.execute_script("return document.body.scrollHeight")
if new_height == last_height:
log("Reached the bottom of the page or no new content loaded.")
return False
last_height = new_height
scroll_count += 1
log(f"Reached max scroll count {max_scroll_count}")
return False
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4. Main Function
The main function initializes the WebDriver, navigates to the target URL, and calls the scroll_page function. It also ensures the browser closes properly after the script finishes.
def main():
url = "https://reddit.com"
# Initialize the WebDriver
driver = webdriver.Chrome()
try:
driver.get(url)
scroll_page(driver)
# Keep the browser open for 60 seconds after scrolling
time.sleep(60)
finally:
driver.quit()
if __name__ == "__main__":
main()
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Running the Script
To run this script, make sure you have Selenium installed and the Chrome WebDriver available on your system. You can install Selenium using pip:
pip install selenium |
Download the appropriate Chrome WebDriver for your Chrome version from the official site and ensure it’s in your system PATH or specify its location when initializing the WebDriver.
Conclusion
This script automates the process of scrolling through a web page using Selenium, making it easier to scrape content from sites with infinite scrolling. By customizing the max_scroll_count and scroll_pause_time, you can adapt the script to different websites and use cases. Happy coding!