When a website like Glassdoor changes its structure, your web scraper might stop working as expected because it relies on specific HTML elements and their attributes to extract data. To update your scraper, you need to follow these steps:
1. Review the Changes on the Website
Open Glassdoor in your browser and examine the page where you noticed the scraper failure. Use browser developer tools (usually accessed by pressing F12 or right-clicking and choosing "Inspect") to look at the HTML structure of the page.
2. Update Your Selectors
Based on your observations, update the selectors in your scraper code to match the new HTML structure. Selectors may include:
- Element IDs (e.g.,
#element-id
) - Class names (e.g.,
.element-class
) - Tag names (e.g.,
div
,span
) - Attributes (e.g.,
[attribute='value']
) - XPath expressions
- CSS selectors
3. Test Your Updated Scraper
Run your scraper with the updated selectors and verify that it works correctly. If it doesn't, you may need to re-examine the webpage and adjust the selectors further.
4. Handle Potential Dynamic Content
If Glassdoor uses JavaScript to dynamically load content, you may need to use tools like Selenium or Puppeteer that can execute JavaScript and wait for content to load before scraping.
5. Respect the Website's Terms and Conditions
Before scraping any website, always review its terms and conditions. Scraping may be against the site's policy, and you should ensure that your activity is compliant with their rules and the law.
Python Example
Let's say you have a Python scraper using BeautifulSoup, and you need to update it:
from bs4 import BeautifulSoup
import requests
# Fetch the webpage
url = 'https://www.glassdoor.com/Job/jobs.htm'
response = requests.get(url)
html_content = response.text
# Parse the webpage with BeautifulSoup
soup = BeautifulSoup(html_content, 'html.parser')
# Update the selectors based on the new structure
# For example, if the job listings are now in a div with a new class name:
new_class_name = 'new-job-listing-class'
job_listings = soup.find_all('div', class_=new_class_name)
# Extract the desired data
for job in job_listings:
# Update the extraction logic based on the new structure
title = job.find('a', class_='new-title-class').text.strip()
company = job.find('div', class_='new-company-class').text.strip()
# ...and so on
# Continue with the rest of your scraping logic
JavaScript Example
If you're using JavaScript with a headless browser like Puppeteer:
const puppeteer = require('puppeteer');
(async () => {
const browser = await puppeteer.launch();
const page = await browser.newPage();
await page.goto('https://www.glassdoor.com/Job/jobs.htm');
// Update the selectors based on the new structure
const newSelector = '.new-job-listing-class';
const jobListings = await page.$$(newSelector);
for (let job of jobListings) {
// Update the extraction logic based on the new structure
const title = await job.$eval('.new-title-class', el => el.innerText.trim());
const company = await job.$eval('.new-company-class', el => el.innerText.trim());
// ...and so on
console.log({ title, company });
}
await browser.close();
})();
Remember, web scraping can be a fragile process due to its reliance on the structure of third-party websites, which you cannot control. It's essential to create scrapers that are as resilient as possible, possibly by using more general selectors, and to monitor your scrapers regularly to ensure they continue to function correctly. Setting up error detection, logging, and alerting mechanisms can help you promptly identify when a scraper breaks due to website changes.