Can Pholcus render pages like a real browser?

Pholcus is a distributed, high-concurrency, and powerful web crawler software written in Go language (also known as Golang). While Pholcus provides a lot of features for web scraping, it does not inherently render pages like a real browser. Rendering pages like a real browser often involves executing JavaScript and handling dynamic content, which requires a browser engine.

To render pages like a real browser, web scrapers often use tools like Selenium, Puppeteer, or headless browsers like Headless Chrome or Headless Firefox. These tools can control a browser programmatically to interact with web pages, execute JavaScript, and handle AJAX calls just like a user would when using a web browser.

If you need to scrape a website with dynamic content using Pholcus, you would typically integrate it with a headless browser or use a service like Splash, which is a headless browser designed specifically for web scraping with scriptable rendering capabilities.

Here's a conceptual example of how you might use a headless browser with Pholcus in Go, using ChromeDP, which is a Go package that drives browsers that support the Chrome DevTools Protocol:

package main

import (
    "context"
    "log"
    "time"

    "github.com/chromedp/chromedp"
    "github.com/henrylee2cn/pholcus/exec"
    // other necessary Pholcus packages
)

func main() {
    // Initialize Pholcus here
    // ...

    // Run your Pholcus tasks
    // ...

    // Example of using ChromeDP to interact with a headless browser
    ctx, cancel := chromedp.NewContext(context.Background())
    defer cancel()

    // Run tasks
    var htmlContent string
    err := chromedp.Run(ctx,
        chromedp.Navigate(`https://example.com`),
        // Wait for the footer element is visible
        chromedp.WaitVisible(`footer`),
        // Retrieve the HTML of the page
        chromedp.OuterHTML(`html`, &htmlContent, chromedp.ByQuery),
    )
    if err != nil {
        log.Fatal(err)
    }

    // Use Pholcus to process the `htmlContent` as needed
    // ...

    // Close Pholcus properly
    // ...
}

Please note that the above code is a simplified example to illustrate the concept. In practice, you would need to integrate the headless browser operations within your Pholcus tasks and logic.

As for JavaScript, there are no direct bindings for Pholcus since it's a Go package, but you can use Puppeteer, which is a Node library that provides a high-level API to control Chrome or Chromium over the DevTools Protocol:

const puppeteer = require('puppeteer');

(async () => {
  // Launch the browser
  const browser = await puppeteer.launch();
  const page = await browser.newPage();

  // Navigate to the page
  await page.goto('https://example.com');

  // Wait for the necessary element to load
  await page.waitForSelector('footer');

  // Get the page content
  const htmlContent = await page.content();

  // Process the `htmlContent` with your JavaScript scraping logic

  // Close the browser
  await browser.close();
})();

In this JavaScript example, Puppeteer acts as a real browser, rendering the page completely with JavaScript execution. You would then use your scraping logic to process the htmlContent.

Remember that when you're scraping websites that require rendering, you should always check the website's robots.txt file and terms of service to make sure you're allowed to scrape it, and you should scrape responsibly to avoid overloading the website's servers.