Bypassing Login Requirements on Java-Based Government Websites for Web Scraping

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Bypassing Login Requirements on Java-Based Government Websites for Web Scraping

When scraping government websites built with Java technologies, you may encounter login pages that seem to block your access to public records. This article demonstrates how to bypass these requirements using a practical example from a county records system.

Identifying Java-Based Government Sites

Java-based government websites can be identified by several characteristics:

  • URLs ending with .JSP extension
  • JSessionID cookies in network requests
  • Two-step request processes for data retrieval

These sites often return HTML responses rather than JSON, making extraction slightly more complex but still manageable.

The Login Bypass Process

When faced with a login page on a public records system, here’s a straightforward approach to bypass it:

  1. Obtain a valid JSessionID cookie by simply visiting the site
  2. Add the “isLoggedInAsPublic=true” parameter to your cookie
  3. Include both in your request headers

This simple technique often works because many government sites don’t implement proper authentication for publicly available records.

Making the Requests

The example demonstrates a two-step request process typical of Java frameworks:

import fetch from 'node-fetch';
import cheerio from 'cheerio';
import fs from 'graceful-fs';

async function getCookie() {
  try {
    const res = await fetch("[WEBSITE_URL]");
    const cookies = res.headers.raw()['set-cookie'];
    return cookies;
  } catch (error) {
    console.log(`Error at getCookie: ${error.message}`);
  }
}

(async () => {
  const cookie = await getCookie();
  
  const startDate = encodeURIComponent("4/1/2024");
  const endDate = encodeURIComponent("4/30/2024");
  
  const res1 = await fetch(`[ENDPOINT_URL]?startDate=${startDate}&endDate=${endDate}`, {
    headers: {
      cookie: `${cookie}; isLoggedInAsPublic=true`
    }
  });
  
  const res2 = await fetch("[RESULTS_URL]", {
    headers: {
      cookie: `${cookie}; isLoggedInAsPublic=true`
    }
  });
  
  const html = await res2.text();
  const $ = cheerio.load(html);
  
  const results = [];
  $("table tr").each((i, elem) => {
    const tds = $(elem).find("td");
    if (tds.length > 0) {
      results.push({
        docId: $(tds[0]).text().trim(),
        description: $(tds[1]).text().trim()
      });
    }
  });
  
  console.log(results);
})();

Parsing the HTML Response

After making the requests, you’ll need to extract the data from the HTML response. Cheerio is an excellent tool for this purpose:

  1. Load the HTML into Cheerio
  2. Target the table rows containing the data
  3. Extract the necessary information from each row
  4. Structure the data into a usable format

Weaknesses in Government Site Security

The example revealed an interesting security weakness: sequential document IDs. Instead of using hashed UIDs or random identifiers, the system used incremental numbers (8560, 8561, etc.), making it trivially easy to scrape the entire document database sequentially.

This type of basic security oversight is surprisingly common in government websites, where database architecture may not follow modern security practices.

Conclusion

Java-based government sites often contain valuable public records that can be accessed programmatically despite appearing to require login credentials. By understanding how these systems work and leveraging simple techniques like cookie manipulation, you can efficiently extract the data you need for your projects.

Remember that while public records are designed to be accessible, always ensure your scraping activities comply with the site’s terms of service and relevant regulations.

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