最近,我开始使用Puppeteer爬网。下面是从购物中心提取特定产品名称的代码。
const puppeteer = require('puppeteer');
(async () => {
const width = 1600, height = 1040;
const option = { headless: false, slowMo: true, args: [`--window-size=${width},${height}`] };
const browser = await puppeteer.launch(option);
const page = await browser.newPage();
const vp = {width: width, height: height};
await page.setViewport(vp);
const navigationPromise = page.waitForNavigation();
await page.goto('https://shopping.naver.com/home/p/index.nhn');
await navigationPromise;
await page.waitFor(2000);
const textBoxId = 'co_srh_input';
await page.type('.' + textBoxId, '양말', {delay: 100});
await page.keyboard.press('Enter');
await page.waitFor(5000);
await page.waitForSelector('div.info > a.tit');
const stores = await page.evaluate(() => {
const links = Array.from(document.querySelectorAll('div.info > a.tit'));
return links.map(link => link.innerText).slice(0, 10) // 10개 제품만 가져오기
});
console.log(stores);
await browser.close();
})();
我有一个问题。如何将爬网的结果输出到HTML文档(不使用数据库)?请使用示例代码进行解释。
答案 0 :(得分:2)
您可以使用以下write_file
函数,当Promise
成功或失败时,该函数返回resolves或rejects的fs.writeFile()
。
然后,您可以从您的匿名异步功能中await
Promise
,并检查是否将数据写入文件:
'use strict';
const fs = require('fs');
const puppeteer = require('puppeteer');
const write_file = (file, data) => new Promise((resolve, reject) => {
fs.writeFile(file, data, 'utf8', error => {
if (error) {
console.error(error);
reject(false);
} else {
resolve(true);
}
});
});
(async () => {
// ...
const stores = await page.evaluate(() => {
return Array.from(document.querySelectorAll('div.info > a.tit'), link => link.innerText).slice(0, 10); // 10개 제품만 가져오기
});
if (await write_file('example.html', stores.toString()) === false) {
console.error('Error: Unable to write stores to example.html.');
}
// ...
});
答案 1 :(得分:1)
const puppeteer = require("puppeteer");
const fs = require("fs");
async function run() {
const browser = await puppeteer.launch();
const page = await browser.newPage();
await page.goto("https://www.google.com/", { waitUntil: "networkidle2" });
// hacky defensive move but I don't know a better way:
// wait a bit so that the browser finishes executing JavaScript
await page.waitFor(1 * 1000);
const html = await page.content();
fs.writeFileSync("index.html", html);
await browser.close();
}
run();