Puppeteer
Browser Automation Library. Puppeteer = Node.js + Chrome. Open pages, navigate to websites, evaluate Javascript
Installation
npm install puppeteer
Usage
(async () => {
const browser = await puppeteer.launch();
const page = await browser.newPage();
await page.goto('https://joel.tools/merch');
const price = await page.$eval('.price', div => div.textContent);
console.log(price);
await browser.close();
})();
Puppeteer for Firefox
npm install puppeteer-firefox
Browser context to speed up tests
const browser = await puppeteer.launch();
it('should have a pay button', async () => {
const context = await browser.createIncognitoBrowserContext();
const page = await context.newPage();
await page.goto('https://joel.tools/merch');
expect(await page.$('button.gpay-button')).toBeTruthy();
await context.close();
})
Flaky tests (tests that sometimes pass sometimes don't)
it('should pay', async () =>{
const page = await context.newPage();
await page.goto('https://joel.tools/merch/');
await page.waitForSelector('button.gpay-button');
const response = page.waitForResponse(res => res.url().endsWith('/pay'));
await page.click('button.gpay-button');
await response;
assert(await page.$('.successful-purchase'));
});
Extract data
await page.waitForXPath("/html/body/div/a/@title", {timeout: 1000});
const aTags = await page.$x('/html/body/div/a');
for (const aTag of aTags) {
let title = await page.evaluate(aTag => aTag.title, aTag);
console.log(title);
}