我试图用puppeteer废弃一些数据,但对于某些网站,querySelector返回null,我不知道出了什么问题。我在stackoverflow中找到了关于这个问题的一些答案,但没有一个有效。以下是带有示例链接的代码。
const puppeteer = require('puppeteer');
(async () => {
const browser = await puppeteer.launch();
const page = await browser.newPage();
await page.goto('https://www.macys.com/shop/product/the-north-face-mens-
logo-half-dome-t-shirt?ID=2085687&CategoryID=30423&cm_kws=2085687');
const textContent = await page.evaluate(() => {
return document.querySelector('.price');
});
console.log(textContent);
browser.close();
})();
答案 0 :(得分:7)
可能这些元素是通过javascript异步加载的,当你调用.evaluate()时,它们仍然不在DOM中。
尝试使用puppeteer .waitForSelector函数等待选择器
const puppeteer = require('puppeteer');
(async () => {
const browser = await puppeteer.launch();
const page = await browser.newPage();
await page.goto('https://www.macys.com/shop/product/the-north-face-mens-
logo-half-dome-t-shirt?ID=2085687&CategoryID=30423&cm_kws=2085687');
await page.waitForSelector('.price');
const textContent = await page.evaluate(() => {
return document.querySelector('.price');
});
console.log(textContent);
browser.close();
})();
答案 1 :(得分:2)
拍摄完页面后,结果发现我的请求被机器人检测系统阻止了。这是解决方案。我们只需传递更多数据,因此它不会被检测为机器人。如果仍然无效,您可以查看this tutorial。
const puppeteer = require('puppeteer');
// This is where we'll put the code to get around the tests.
const preparePageForTests = async (page) => {
// Pass the User-Agent Test.
const userAgent = 'Mozilla/5.0 (X11; Linux x86_64)' +
'AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.39 Safari/537.36';
await page.setUserAgent(userAgent);
}
(async () => {
const browser = await puppeteer.launch();
const page = await browser.newPage();
await preparePageForTests(page);
// await page.setRequestInterception(true);
await page.goto('websiteURL');
const textContent = await page.evaluate(() => {
return {document.querySelector('yourCSSselector').textContent,
}
});
console.log(textContent);
browser.close();