Scraping Dynamic Web Pages Without Selectors Using AI Vision (TypeScript/JavaScript Tutorial)

Paras Tejpal — Fri, 19 Jun 2026 05:29:11 +0000

****# Scraping Dynamic Web Pages Without Selectors Using AI Vision (TypeScript/JavaScript Tutorial)

Web scraping has traditionally been a game of cat-and-mouse. You spend hours writing fine-tuned CSS selectors or XPath paths, only for the website to change its layout or class names (especially on modern frameworks with generated CSS class names like css-1ux802d), breaking your entire data pipeline overnight.

In this tutorial, we will learn how to build a selector-free scraper using Opticparse, an AI-powered scraping tool that captures webpage screenshots and uses Gemini's multimodal vision intelligence to extract structured JSON data.

We will use the official Opticparse JavaScript/TypeScript SDK to extract data in less than 10 lines of code.

The Concept: AI Vision Scraping

Instead of parsing HTML source code directly, Opticparse:

Launches a headless Chromium instance using Playwright.
Navigates to the target page and takes a full-page snapshot.
Passes the screenshot to an AI Vision Agent (Gemini) along with a text prompt.
Returns clean, parsed JSON matching your description.

Because it mimics how a real human looks at the page, it does not care about dynamic CSS class name changes, shadow DOMs, or obfuscated HTML.

Setup & Installation

Install the official client library:

npm install opticparse-js

Get Your API Key

You can get an API key in two ways:

RapidAPI Hub: Access the API globally on the RapidAPI Opticparse Listing. Subscribe to the Free basic tier to get a RapidAPI Key.
Private Host: If you hosted the Docker microservice container yourself (e.g. on Render), use your private OPTICPARSE_API_KEY.

Code Example: Scraping Hacker News

Let's say we want to scrape the top 5 articles, their link URLs, and score points from the homepage of Hacker News.

Here is how you do it:

import { OpticparseClient } from 'opticparse-js';

// Initialize the client. 
// If using the RapidAPI marketplace, set useRapidApi: true
const client = new OpticparseClient({
  apiKey: 'YOUR_RAPIDAPI_KEY_HERE',
  useRapidApi: true
});

async function runScrape() {
  console.log('Scraping Hacker News articles...');

  try {
    const data = await client.scrape({
      targetUrl: 'https://news.ycombinator.com',
      extractionQuery: 'Extract the top 5 article titles, their link URLs, and score points as a JSON list of objects.',
      viewportWidth: 1280,
      viewportHeight: 1000
    });

    console.log('Scraped Data Output:');
    console.log(JSON.stringify(data, null, 2));

  } catch (error) {
    console.error('Scraping failed:', error);
  }
}

runScrape();

Sample Output

The client will automatically handle the asynchronous execution, image loading, and return a clean, fully-typed JSON structure:

[
  {
    "title": "Why I still use Vim",
    "url": "https://example.com/vim",
    "points": 142
  },
  {
    "title": "Show HN: Opticparse - AI Visual Scraper",
    "url": "https://github.com/parastejpal987-cmyk/opticparse",
    "points": 98
  }
]

Advanced Options

The SDK client supports configuring the browser environment to handle dynamic loading states:


typescript
const result = await client.scrape({
  targetUrl: 'https://example.com',
  extractionQuery: 'Extract details...',

  // Custom screen sizes for responsive layouts
  viewportWidth: 1920,
  viewportHeight: 1080,

  // Wait until page is completely loaded ('networkidle' | 'load' | 'domcontentloaded')
  waitUntil: 'networkidle',

  // Adjust timeout threshold (in milliseconds) for slower connec