I am currently developing a node.js script that needs to launch a headful chromium instance using Puppeteer and then make a screenshot of a page every 3 seconds, this is my code :
const puppeteer = require('puppeteer');
async function init (){
const browser = await puppeteer.launch({headless: true});
const page = await browser.newPage();
await page.goto('https://example.com');
screenshot(page)
};
async function screenshot(page){
let buffer = await page.screenshot();
let imageBuffer = buffer.toString('base64');
// save imageBuffer to database
setTimeout(screenshot, 3000, page)
}
My current issue is that I need the user to still be able to normally navigate on the browser and on his computer but this impossible as :
The page lags when making the screenshot as you can see on the following video : https://youtu.be/Tl2w-qKckkc
The browser window focuses and goes on top of all the windows when making the screenshot.
I also tried using Playwright but the same bug occurs when using it with chromium. Can someone please help.
In Playwright, do the following:
// Affects all the platforms.
const page = await browser.newPage({ viewport: null });
// Local fix for those using Apple hardware with Retina displays.
const page = await browser.newPage({ deviceScaleFactor: 2 });
I posted a detailed reply at https://github.com/microsoft/playwright/issues/2576. Please feel free to follow up and ask questions / request features there!
Related
I am trying to build a simple scraper for this website by using puppeteer.
The code goes as follows:
const browser = await puppeteer.launch({
headless: false
});
const page = await browser.newPage();
let pagelink = "https://www.speisekarte.de/berlin/restaurants?page=1"
await page.waitFor(3 * 1000);
await page.goto(pagelink);
await page.waitFor(3 * 1000);
await page.waitForSelector("#notice")
However, I cannot access the overlay notice for the cookies which should have the Id "notice".
This does not work either for await page.waitForSelector("#notice")
in my puppeteer code.
Nor with document.getElementById("notice") in Chromium, if I use the console of Chromium during the session manually. Also, it does not work, if I use it in Firefox's console. Funnily enough, chunks like
document.querySelectorAll("button")
work as expected. I checked with a colleague and she can access the element using the above mentioned queries in her Chrome and in her Firefox browser. She also uses a Mac. Any idea, what is happening here? Any help would be much appreciated.
I want to start a chromium browser instant headless, do some automated operations, and then turn it visible before doing the rest of the stuff.
Is this possible to do using Puppeteer, and if it is, can you tell me how? And if it is not, is there any other framework or library for browser automation that can do this?
So far I've tried the following but it didn't work.
const browser = await puppeteer.launch({'headless': false});
browser.headless = true;
const page = await browser.newPage();
await page.goto('https://news.ycombinator.com', {waitUntil: 'networkidle2'});
await page.pdf({path: 'hn.pdf', format: 'A4'});
Short answer: It's not possible
Chrome only allows to either start the browser in headless or non-headless mode. You have to specify it when you launch the browser and it is not possible to switch during runtime.
What is possible, is to launch a second browser and reuse cookies (and any other data) from the first browser.
Long answer
You would assume that you could just reuse the data directory when calling puppeteer.launch, but this is currently not possible due to multiple bugs (#1268, #1270 in the puppeteer repo).
So the best approach is to save any cookies or local storage data that you need to share between the browser instances and restore the data when you launch the browser. You then visit the website a second time. Be aware that any state the website has in terms of JavaScript variable, will be lost when you recrawl the page.
Process
Summing up, the whole process should look like this (or vice versa for headless to headfull):
Crawl in non-headless mode until you want to switch mode
Serialize cookies
Launch or reuse second browser (in headless mode)
Restore cookies
Revisit page
Continue crawling
As mentioned, this isn't currently possible since the headless switch occurs via Chromium launch flags.
I usually do this with userDataDir, which the Chromium docs describe as follows:
The user data directory contains profile data such as history, bookmarks, and cookies, as well as other per-installation local state.
Here's a simple example. This launches a browser headlessly, sets a local storage value on an arbitrary page, closes the browser, re-opens it headfully, retrieves the local storage value and prints it.
const puppeteer = require("puppeteer"); // ^18.0.4
const url = "https://www.example.com";
const opts = {userDataDir: "./data"};
let browser;
(async () => {
{
browser = await puppeteer.launch({...opts, headless: true});
const [page] = await browser.pages();
await page.goto(url, {waitUntil: "domcontentloaded"});
await page.evaluate(() => localStorage.setItem("hello", "world"));
await browser.close();
}
{
browser = await puppeteer.launch({...opts, headless: false});
const [page] = await browser.pages();
await page.goto(url, {waitUntil: "domcontentloaded"});
const result = await page.evaluate(() => localStorage.getItem("hello"));
console.log(result); // => world
}
})()
.catch(err => console.error(err))
.finally(() => browser?.close())
;
Change const opts = {userDataDir: "./data"}; to const opts = {}; and you'll see null print instead of world; the user data doesn't persist.
The answer from a few years ago mentions issues with userDataDir and suggests a cookies solution. That's fine, but I haven't had any issues with userDataDir so either they've been resolved on the Puppeteer end or my use cases haven't triggered the issues.
There's a useful-looking answer from a reputable source in How to turn headless on after launch? but I haven't had a chance to try it yet.
i'm actually trying to use puppeteer for scraping and i need to use my current chrome to keep all my credentials and use it instead of relogin and type password each time which is a really time lose !
is there a way to connect it ? how to do that ?
i'm actually using node v11.1.0
and puppeteer 1.10.0
let scrape = async () => {
const browser = await log()
const page = await browser.newPage()
const delayScroll = 200
// Login
await page.goto('somesite.com');
await page.type('#login-email', '*******);
await page.type('#login-password', "******");
await page.click('#login-submit');
// Wait to login
await page.waitFor(1000);
}
and now it will be perfect if i do not need to use that and go on page (headless, i dont wan't to see the page opening i'm just using the info scraping in node) but with my current chrome who does not need to login to have information i need. (because at the end i want to use it as an extension of chrome)
thx in advance if someone knows how to do that
First welcome to the community.
You can use Chrome instead of Chromium but sincerely in my case, I get a lot of errors and cause a mess with my personal tabs. So you can create and save a profile, then you can login with a current or a new account.
In your code you have a function called "log" I'm guessing that there you set launch puppeeteer.
const browser = await log()
Into that function use arguments and create a relative directory for your profile data:
const browser = await puppeteer.launch({
args: ["--user-data-dir=./Google/Chrome/User Data/"]
});
Run your application, login with an account and the next time you enter you should see your credentials
Any doubt please add a comment.
I am connected to a browser using a ws endpoint (puppeteer.connect({ browserWSEndpoint: '' })).
When I launch the browser that I ultimately connect to, is there a way to launch this in incognito?
I know I can do something like this:
const incognito = await this.browser.createIncognitoBrowserContext();
But it seems like the incognito session is tied to the originally opened browser. I just want it to be by itself.
I also see you can do this:
const baseOptions: LaunchOptions = { args: ['--incognito']};
But I am not sure if this is the best way or not.
Any advice would be appreciated. Thank you!
The best way to accomplish your goal is to launch the browser directly into incognito mode by passing the --incognito flag to puppeteer.launch():
const browser = await puppeteer.launch({
args: [
'--incognito',
],
});
Alternatively, you can create a new incognito browser context after launching the browser using browser.createIncognitoBrowserContext():
const browser = await puppeteer.launch();
const context = await browser.createIncognitoBrowserContext();
You can check whether a browser context is incognito using browserContext.isIncognito():
if (context.isIncognito()) { /* ... */ }
the solutions above didn't work for me:
an incognito window is created, but then when the new page is created, it is no longer incognito.
The solution that worked for me was:
const browser = await puppeteer.launch();
const context = await browser.createIncognitoBrowserContext();
const page = await context.newPage();
then you can use page and it's an incognito page
For Puppeteer sharp it's rather messy but this seems to work.. Hopefully it helps someone.
using (Browser browser = await Puppeteer.LaunchAsync(options))
{
// create the async context
var context = await browser.CreateIncognitoBrowserContextAsync();
// get the page created by default when launch async ran and close it whilst keeping the browser active
var browserPages = await browser.PagesAsync();
await browserPages[0].CloseAsync();
// create a new page using the incognito context
using (Page page = await context.NewPageAsync())
{
// do something
}
}
I am trying to use puppeteer to measure how fast a set of web sites loads in my environment. My focus is on the quality of network connection and network speed, so I am happy to know the the time taken for a page to load, for a layman's definition of load, when all images and html is downloaded by browser.
By using puppeteer I can run the test repeatedly and measure the difference in load times precisely.
I can see that in 64.0.3240.0 (r508693) page.getMetrics and event: 'metrics' have landed, which should help me in getting what I am looking for.
But being a newbie in node and js I am not sure how to read the page.getMetrics and which of the different key/value pairs give a useful information in my context.
My current pathetic attempt at reading metrics is as follows:
const puppeteer = require('puppeteer');
async function run() {
const browser = await puppeteer.launch({args: ['--no-sandbox', '--disable-setuid-sandbox']});
const page = await browser.newPage();
page.on('load', () => console.log("Loaded: " + page.url()));
await page.goto('https://google.com');
const metrics = page.getMetrics();
console.log(metrics.Documents, metrics.Frames, metrics.JSEventListeners);
await page.goto('https://yahoo.com');
await page.goto('https://bing.com');
await page.goto('https://github.com/login');
browser.close();
}
run();
Any help in getting this code to some thing more respectable is much appreciated :)
in recent versions you have page.metrics() available:
It will return an object with a bunch of numbers including:
The timestamp when the metrics sample was taken
Combined durations of all page layouts
Combined duration of all tasks performed by the browser.
Check out the docs for the full list
You can use it like this:
await page.goto('https://github.com/login');
const gitMetrics = await page.metrics();
console.log(gitMetrics.Timestamp)
console.log(gitMetrics.TaskDuration)