Puppeteer 用处

配置

Node环境配置

下载并安装NodeJS:

wget https://nodejs.org/dist/v8.12.0/node-v8.12.0-linux-x.tar.xz
tar xf node-v8.12.0-linux-x.tar.xz
mv node-v8.12.0-linux-x /usr/local/lib
ln -s /usr/local/lib/node-v8.12.0-linux-x/bin/npm /usr/local/bin/
ln -s /usr/local/lib/node-v8.12.0-linux-x/bin/node /usr/local/bin/

*(可选)配置淘宝的源，加速npm包的下载：

npm config set registry https://registry.npm.taobao.org

安装Puppeteer

配置淘宝的Puppeteer下载源，用于安装Chromium：

export PUPPETEER_DOWNLOAD_HOST=https://storage.googleapis.com.cnpmjs.org
npm i puppeteer

国内不配置时会在卡在下载Chromium

示例

新建一个test.js

const puppeteer = require('puppeteer');

(async () => {
 const browser = await puppeteer.launch({
 ignoreHTTPSErrors: true,
 headless: false,
 args: ['--no-sandbox']
 });
 const page = await browser.newPage();
 await page.goto('https://intest.tech');
 await page.waitFor(5e3);
 await browser.close();
})();

运行：

node test.js

截图

知识点

const puppeteer = require('puppeteer');

(async () => {
const browser = await (puppeteer.launch({
// 若是手动下载的chromium需要指定chromium地址, 默认引用地址为 /项目目录/node_modules/puppeteer/.local-chromium/
executablePath: '/Users/huqiyang/Documents/project/z/chromium/Chromium.app/Contents/MacOS/Chromium',
//设置超时时间
timeout: 15000,
//如果是访问https页面 此属性会忽略https错误
ignoreHTTPSErrors: true,
// 打开开发者工具, 当此值为true时, headless总为false
devtools: false,
// 关闭headless模式, 会打开浏览器
headless: false
}));
const page = await browser.newPage();
await page.goto('https://www.jianshu.com/u/40909ea33e50');
await page.screenshot({
path: 'jianshu.png',
type: 'png',
// quality: 100, 只对jpg有效
fullPage: true,
// 指定区域截图，clip和fullPage两者只能设置一个
// clip: {
// x: 0,
// y: 0,
// width: 1000,
// height: 40
// }
});
browser.close();
})();

进阶，获取网易云音乐的歌词和评论

网易云音乐的API经过AES和RSA算法加密，需要携带加密的信息通过POST方式请求才能获取到数据。但 Puppeteer 出现后，这些都不重要了，只要它页面上显示了，通过 Puppeteer 都能获取到该元素。

知识点

const fs = require('fs');
const puppeteer = require('puppeteer');

(async () => {
const browser = await (puppeteer.launch({ executablePath: '/Users/huqiyang/Documents/project/z/chromium/Chromium.app/Contents/MacOS/Chromium', headless: false }));
const page = await browser.newPage();
// 进入页面
await page.goto('https://music.163.com/#');

// 点击搜索框拟人输入 鬼才会想起
const musicName = '鬼才会想';
await page.type('.txt.j-flag', musicName, {delay: 0});

// 回车
await page.keyboard.press('Enter');

// 获取歌曲列表的 iframe
await page.waitFor(2000);
let iframe = await page.frames().find(f => f.name() === 'contentFrame');
const SONG_LS_SELECTOR = await iframe.$('.srchsongst');

// 获取歌曲 鬼才会想起 的地址
const selectedSongHref = await iframe.evaluate(e => {
const songList = Array.from(e.childNodes);
const idx = songList.findIndex(v => v.childNodes[1].innerText.replace(/\s/g, '') === '鬼才会想起');
return songList[idx].childNodes[1].firstChild.firstChild.firstChild.href;
}, SONG_LS_SELECTOR);

// 进入歌曲页面
await page.goto(selectedSongHref);

// 获取歌曲页面嵌套的 iframe
await page.waitFor(2000);
iframe = await page.frames().find(f => f.name() === 'contentFrame');

// 点击 展开按钮
const unfoldButton = await iframe.$('#flag_ctrl');
await unfoldButton.click();

// 获取歌词
const LYRIC_SELECTOR = await iframe.$('#lyric-content');
const lyricCtn = await iframe.evaluate(e => {
return e.innerText;
}, LYRIC_SELECTOR);

console.log(lyricCtn);

// 截图
await page.screenshot({
path: '歌曲.png',
fullPage: true,
});

// 写入文件
let writerStream = fs.createWriteStream('歌词.txt');
writerStream.write(lyricCtn, 'UTF8');
writerStream.end();

// 获取评论数量
const commentCount = await iframe.$eval('.sub.s-fc3', e => e.innerText);
console.log(commentCount);

// 获取评论
const commentList = await iframe.$$eval('.itm', elements => {
const ctn = elements.map(v => {
return v.innerText.replace(/\s/g, '');
});
return ctn;
});
console.log(commentList);
})();

参考

https://github.com/cnpm/cnpmjs.org/issues/1246#issuecomment-341631992