Missing data when scraping list of cards with images with Puppeteer and Cheerio-CodePudding

I'm trying to scrape a page of card items. I'd like to extract the titles, prices, image sources and other properties from these cards. However, when I scrape with Puppeteer and Cheerio, some of the data is missing. See the image below:

How can I make sure all of the data comes through?

This is my code:

(async () => {
  try {
    const StealthPlugin = require("puppeteer-extra-plugin-stealth");
    puppeteer2.use(StealthPlugin());
    const browser = await puppeteer2.launch({
      executablePath: "/usr/bin/chromium-browser",
      headless: true,
      args: [
        "--no-sandbox",
        "--disable-setuid-sandbox",
        "--user-agent="   USER_AGENT   "",
      ],
    });
    
    const page = await browser.newPage({ignoreHTTPSErrors: true});
    await page.setDefaultNavigationTimeout(0);
    await page.goto("https://es.wallapop.com/search?keywords=", {
      waitUntil: "networkidle0",
    });
    await page.waitForTimeout(30000);
    
    const body = await page.evaluate(() => {
      return document.querySelector("body").innerHTML;
    });
    
    var $ = cheerio.load(body);
    
    const pageItems = $(".ItemCardList__item .ng-star-inserted")
      .toArray()
      .map((item) => {
        const $item = $(item);
        return {
          //  id: $item.attr('data-adid'), c10420p([^i]*)\/
          id: uuid.v4(),
          title: $item.find(".ItemCard__info").text(),
          link: "https://es.wallapop.com/item/",
          image: $item.find(".w-100").attr("src"),
          price: $item
            .find(".ItemCard__price")
            .text()
            .replace(/[_\W] /g, ""),
          empresa: "wallapop",
        };
      });
    
    const allItems = items.concat(pageItems);
    console.log(
      pageItems.length,
      "items retrieved",
      allItems.length,
      "acumulat  ed",
    );
    // ...

CodePudding user response：

I didn't bother testing with Cheerio, but this might be a good example of the "using a separate HTML parser with Puppeteer" antipattern.

Using plain Puppeteer works fine for me:

const puppeteer = require("puppeteer"); // ^19.6.3

const url = "<Your URL>";

let browser;
(async () => {
  browser = await puppeteer.launch();
  const [page] = await browser.pages();
  await page.goto(url, {waitUntil: "domcontentloaded"});
  await page.waitForSelector(".ItemCard__info");
  const items = await page.$$eval(".ItemCardList__item", els =>
    els.map(e => ({
      title: e.querySelector(".ItemCard__info").textContent.trim(),
      img: e.querySelector("img").getAttribute("src"),
      price: e.querySelector(".ItemCard__price").textContent.trim(),
    }))
  );
  console.log(items);
  console.log(items.length); // => 40
})()
  .catch(err => console.error(err))
  .finally(() => browser?.close());

Other remarks:

Watch out for await page.setDefaultNavigationTimeout(0); which can hang your process indefinitely. If a navigation doesn't resolve in a few minutes, something has gone wrong and it's appropriate to throw and log diagnostics so the maintainer can look at the situation. Or at least programmatically re-try the operation.
page.waitForTimeout() is poor practice and rightfully deprecated, but can be useful for checking for dynamic loads, as you're probably attempting to do here.

Instead of

const body = await page.evaluate(() => {
  return document.querySelector('body').innerHTML;
});

use const body = await page.content();.