So I have an line which I can just paste manually into the Devtools Console in a browser. Is there any way to make pupeteer execute it? After searching I havent found anything, sorry if this has been answered already, I am quite new.
For those who care its an Line to buy an listing of an Item, Example:
BuyMarketListing('listing', '3555030760772417847', 730, '2', '24716958303')
It looks like you're looking for page.evaluate(). Here is a link to the Puppeteer's documentation for it. You can pass in a string or an anonymous function containing the lines you want to evaluate in the page.
const puppeteer = require('puppeteer');
(async () => {
const browser = await puppeteer.launch();
const page = await browser.newPage();
await page.goto('https://example.com');
await page.evaluate(() => { insert lines here }); // page.evaluate() should run the lines in the browser console
await browser.close();
})();
I'm practicing with Telegram bots and puppeteer so I've decided to create a bot to order pizza from a specific website.
Once the bot has taken the order he needs to place the data he took to inputs on the page, here how it looks like:
These two fields are spans and when puppeteer clicks on the enabled one (left) he gets an input to complete. Then when the first input is done puppeteer has to do the exact same procedure with the second field: click on <span> tag, place data in input, etc.
But the thing is that there is a small-time gap between the completion of the first field and activation of the second one. My bot doesn't recognize this gap and clicks on the second field's span instantly (and of course it doesn't work).
Here's a code fragment:
await page.waitForXPath('//*[#id="select2-chosen-2"]', {visible: true})
const [secondSpan] = await page.$x('//*[#id="select2-chosen-2"]')
await secondSpan.click()
When I type node bot with this fragment I get no errors or warnings. But as I said it takes some time for the second field to activate. I've found a function to make puppeeter stop the execution of my code for a certain time period: page.waitForTimeout().
Here the example of usage in puppeteer's documentation:
const puppeteer = require('puppeteer');
(async () => {
const browser = await puppeteer.launch();
const page = await browser.newPage();
page.waitForTimeout(1000).then(() => console.log('Waited a second!'));
await browser.close();
})();
https://pptr.dev/#?product=Puppeteer&version=v10.1.0&show=api-pagewaitfortimeoutmilliseconds
Here's my case:
await page.waitForXPath('//*[#id="select2-chosen-2"]', {visible: true})
const [secondSpan] = await page.$x('//*[#id="select2-chosen-2"]')
page.waitForTimeout(1500)
await secondSpan.click()
This code also doesn't show any error, but it also doesn't click on the field. When I add await to page.waitForTimeout() I get this error:
Error: Node is either not visible or not an HTMLElement
How can I fix it?
So all I needed was to put this code:
await page.click('#s2id_home-number-modal')
Or using XPath:
const [secondSpan] = await page.$x('//*[#id="select2-chosen-2"]')
await secondSpan.click()
into .then() method, that is called after page.setTimeout(500).
All in all, it looks like this (by the way, I've changed some selectors, but it's not a big deal):
await page.waitForTimeout(500).then(async () => {
await page.click('#s2id_home-number-modal')
})
I'm new to pupetteer and I'm trying to understand how it's actually working through some examples:
So basically what I'm trying to do in this example is to extract number of views of a Youtube video. I've written a js line on the Chrome console that let me extract this information:
document.querySelector('#count > yt-view-count-renderer > span.view-count.style-scope.yt-view-count-renderer').innerText
Which worked well. However when I did the same with my pupetteer code he doesn't recognize the element I queried.
const puppeteer = require('puppeteer')
const getData = async () => {
const browser = await puppeteer.launch()
const page = await browser.newPage()
await page.goto('https://www.youtube.com/watch?v=T5GSLc-i5Xo')
await page.waitFor(1000)
const result = await page.evaluate(() => {
let views = document.querySelector('#count > yt-view-count-renderer > span.view-count.style-scope.yt-view-count-renderer').innerText
return {views}
})
browser.close()
return result
}
getData().then(value => {
console.log(value)
})
I finally did it using ytInitialData object. However I'd like to understand the reason why my first code didn't work.
Thanks
It seems that wait for 1000 is not enough.
Try your solution with https://try-puppeteer.appspot.com/ and you will see.
However if you try the following solution, you will get the correct result
const browser = await puppeteer.launch();
const page = await browser.newPage();
await page.goto('https://www.youtube.com/watch?v=T5GSLc-i5Xo');
await page.waitForSelector('span.view-count');
const views = await page.evaluate(() => document.querySelector('span.view-count').textContent);
console.log('Number of views: ' + views);
await browser.close();
Do not use hand made timeout to wait a page to load, unless you are testing whether the page can only in that amount of time. Differently from selenium where sometimes you do not have a choice other than using a timeout, with puppeteer you should always find some await function you can use instead of guessing a "good" timeout. As answered by Milan Hlinák, look into the page HTML code and figure out some HTML tag you can wait on, instead of using a timeout. Usually, wait for the HTML element(s) you test require in order to work properly. On you case, the span.view-count, as already answered by Milan Hlinák:
await page.waitForSelector('span.view-count');
I am working on creating PDF from web page.
The application on which I am working is single page application.
I tried many options and suggestion on https://github.com/GoogleChrome/puppeteer/issues/1412
But it is not working
const browser = await puppeteer.launch({
executablePath: 'C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe',
ignoreHTTPSErrors: true,
headless: true,
devtools: false,
args: ['--no-sandbox', '--disable-setuid-sandbox']
});
const page = await browser.newPage();
await page.goto(fullUrl, {
waitUntil: 'networkidle2'
});
await page.type('#username', 'scott');
await page.type('#password', 'tiger');
await page.click('#Login_Button');
await page.waitFor(2000);
await page.pdf({
path: outputFileName,
displayHeaderFooter: true,
headerTemplate: '',
footerTemplate: '',
printBackground: true,
format: 'A4'
});
What I want is to generate PDF report as soon as Page is loaded completely.
I don't want to write any type of delays i.e. await page.waitFor(2000);
I can not do waitForSelector because the page has charts and graphs which are rendered after calculations.
Help will be appreciated.
You can use page.waitForNavigation() to wait for the new page to load completely before generating a PDF:
await page.goto(fullUrl, {
waitUntil: 'networkidle0',
});
await page.type('#username', 'scott');
await page.type('#password', 'tiger');
await page.click('#Login_Button');
await page.waitForNavigation({
waitUntil: 'networkidle0',
});
await page.pdf({
path: outputFileName,
displayHeaderFooter: true,
headerTemplate: '',
footerTemplate: '',
printBackground: true,
format: 'A4',
});
If there is a certain element that is generated dynamically that you would like included in your PDF, consider using page.waitForSelector() to ensure that the content is visible:
await page.waitForSelector('#example', {
visible: true,
});
Sometimes the networkidle events do not always give an indication that the page has completely loaded. There could still be a few JS scripts modifying the content on the page. So watching for the completion of HTML source code modifications by the browser seems to be yielding better results. Here's a function you could use -
const waitTillHTMLRendered = async (page, timeout = 30000) => {
const checkDurationMsecs = 1000;
const maxChecks = timeout / checkDurationMsecs;
let lastHTMLSize = 0;
let checkCounts = 1;
let countStableSizeIterations = 0;
const minStableSizeIterations = 3;
while(checkCounts++ <= maxChecks){
let html = await page.content();
let currentHTMLSize = html.length;
let bodyHTMLSize = await page.evaluate(() => document.body.innerHTML.length);
console.log('last: ', lastHTMLSize, ' <> curr: ', currentHTMLSize, " body html size: ", bodyHTMLSize);
if(lastHTMLSize != 0 && currentHTMLSize == lastHTMLSize)
countStableSizeIterations++;
else
countStableSizeIterations = 0; //reset the counter
if(countStableSizeIterations >= minStableSizeIterations) {
console.log("Page rendered fully..");
break;
}
lastHTMLSize = currentHTMLSize;
await page.waitForTimeout(checkDurationMsecs);
}
};
You could use this after the page load / click function call and before you process the page content. e.g.
await page.goto(url, {'timeout': 10000, 'waitUntil':'load'});
await waitTillHTMLRendered(page)
const data = await page.content()
In some cases, the best solution for me was:
await page.goto(url, { waitUntil: 'domcontentloaded' });
Some other options you could try are:
await page.goto(url, { waitUntil: 'load' });
await page.goto(url, { waitUntil: 'domcontentloaded' });
await page.goto(url, { waitUntil: 'networkidle0' });
await page.goto(url, { waitUntil: 'networkidle2' });
You can check this at puppeteer documentation:
https://pptr.dev/#?product=Puppeteer&version=v11.0.0&show=api-pagewaitfornavigationoptions
I always like to wait for selectors, as many of them are a great indicator that the page has fully loaded:
await page.waitForSelector('#blue-button');
In the latest Puppeteer version, networkidle2 worked for me:
await page.goto(url, { waitUntil: 'networkidle2' });
Wrap the page.click and page.waitForNavigation in a Promise.all
await Promise.all([
page.click('#submit_button'),
page.waitForNavigation({ waitUntil: 'networkidle0' })
]);
I encountered the same issue with networkidle when I was working on an offscreen renderer. I needed a WebGL-based engine to finish rendering and only then make a screenshot. What worked for me was a page.waitForFunction() method. In my case the usage was as follows:
await page.goto(url);
await page.waitForFunction("renderingCompleted === true")
const imageBuffer = await page.screenshot({});
In the rendering code, I was simply setting the renderingCompleted variable to true, when done. If you don't have access to the page code you can use some other existing identifier.
You can also use to ensure all elements have rendered
await page.waitFor('*')
Reference: https://github.com/puppeteer/puppeteer/issues/1875
As for December 2020, waitFor function is deprecated, as the warning inside the code tell:
waitFor is deprecated and will be removed in a future release. See
https://github.com/puppeteer/puppeteer/issues/6214 for details and how
to migrate your code.
You can use:
sleep(millisecondsCount) {
if (!millisecondsCount) {
return;
}
return new Promise(resolve => setTimeout(resolve, millisecondsCount)).catch();
}
And use it:
(async () => {
await sleep(1000);
})();
Keeping in mind the caveat that there's no silver bullet to handle all page loads, one strategy is to monitor the DOM until it's been stable (i.e. has not seen a mutation) for more than n milliseconds. This is similar to the network idle solution but geared towards the DOM rather than requests and therefore covers a different subset of loading behaviors.
Generally, this code would follow a page.waitForNavigation({waitUntil: "domcontentloaded"}) or page.goto(url, {waitUntil: "domcontentloaded"}), but you could also wait for it alongside, say, waitForNetworkIdle() using Promise.all() or Promise.race().
Here's a simple example:
const puppeteer = require("puppeteer"); // ^14.3.0
const waitForDOMStable = (
page,
options={timeout: 30000, idleTime: 2000}
) =>
page.evaluate(({timeout, idleTime}) =>
new Promise((resolve, reject) => {
setTimeout(() => {
observer.disconnect();
const msg = `timeout of ${timeout} ms ` +
"exceeded waiting for DOM to stabilize";
reject(Error(msg));
}, timeout);
const observer = new MutationObserver(() => {
clearTimeout(timeoutId);
timeoutId = setTimeout(finish, idleTime);
});
const config = {
attributes: true,
childList: true,
subtree: true
};
observer.observe(document.body, config);
const finish = () => {
observer.disconnect();
resolve();
};
let timeoutId = setTimeout(finish, idleTime);
}),
options
)
;
const html = `<!DOCTYPE html><html lang="en"><head>
<title>test</title></head><body><h1></h1><script>
(async () => {
for (let i = 0; i < 10; i++) {
document.querySelector("h1").textContent += i + " ";
await new Promise(r => setTimeout(r, 1000));
}
})();
</script></body></html>`;
let browser;
(async () => {
browser = await puppeteer.launch({headless: true});
const [page] = await browser.pages();
await page.setContent(html);
await waitForDOMStable(page);
console.log(await page.$eval("h1", el => el.textContent));
})()
.catch(err => console.error(err))
.finally(() => browser?.close())
;
For pages that continually mutate the DOM more often than the idle value, the timeout will eventually trigger and reject the promise, following the typical Puppeteer fallback. You can set a more aggressive overall timeout to fit your needs or tailor the logic to ignore (or only monitor) a particular subtree.
Answers so far haven't mentioned a critical fact: it's impossible to write a one-size-fits-all waitUntilPageLoaded function that works on every page. If it were possble, Puppeteer would surely provide it.
Such a function can't rely on a timeout, because there's always some page that takes longer to load than that timeout. As you extend the timeout to reduce the failure rate, you introduce unnecessary delays when working with fast pages. Timeouts are generally a poor solution, opting out of Puppeteer's event-driven model.
Waiting for idle network requests might not always work if the responses involve long-running DOM updates that take longer than 500ms to trigger a render.
Waiting for the DOM to stop changing might miss slow network requests, long-delayed JS triggers, or ongoing DOM manipulation that might cause the listener never to settle, unless specially handled.
And, of course, there's user interaction: captchas, prompts and cookie/subscription modals that need to be clicked through and dismissed before the page is in a sensible state for a full-page screenshot (for example).
Since every page has different, arbitrary JS behavior, the typical approach is to write event-driven logic that works for a specific page. Making precise, directed assumptions is much better than cobbling together a boatload of hacks that tries to solve every edge case.
If your use case is to write a load event that works on every page, my suggestion is to use some combination of the tools described here that is most balanced to meet your needs (speed vs. accuracy, development time/code complexitiy vs accuracy, etc). Use fail-safes for everything rather than blindly assuming all pages will cooperate with your assumptions. Think hard about what extent you really need to try to handle every web page. Prepare to compromise and accept some degree of failures you can live with.
Here's a quick rundown of the strategies you can mix and match to wait for loads to fit your needs:
page.goto() and page.waitForNavigation() default to the load event, which "is fired when the whole page has loaded, including all dependent resources such as stylesheets and images" (MDN), but this is often too pessimistic; there's no need to wait for a ton of data you don't care about. Often the data is available without waiting for all external resources, so domcontentloaded should be faster. See my post Avoiding Puppeteer Antipatterns for further discussion.
On the other hand, if there are JS-triggered networks requests after load, you'll miss that data. Hence networkidle2 and networkidle0, which wait 500 ms after the number of active network requests are 2 or 0. The motivation for the 2 version is that some sites keep ongoing requests open, which would cause networkidle0 to time out.
If you're waitng for a specific network response that might have a payload (or, for the general case, implementing your own network idle monitor), use page.waitForResponse(). page.waitForRequest(), page.waitForNetworkIdle() and page.on("request", ...) are also useful here.
If you're waiting for a particular selector to be visible, use page.waitForSelector(). If you're waiting for a load on a specific page, identify a selector that indicates the state you want to wait for. Generally speaking, for scripts specific to one page, this is the main tool to wait for the state you want, whether you're extracting data or clicking something. Frames and shadow roots thwart this function.
page.waitForFunction() lets you wait for an arbitrary predicate, for example, checking that the page's HTML or a specific list is a certain length. It's also useful for quickly dipping into frames and shadow roots to wait for predicates that depend on nested state. This function is also handy for detecting DOM mutations.
The most general tool is page.evaluate(), which plugs code into the browser. You can put just about any conditions you want here; most other Puppeteer functions are convenience wrappers for common cases you could implement by hand with evaluate.
I can't leave comments, but I made a python version of Anand's answer for anyone who finds it useful (i.e. if they use pyppeteer).
async def waitTillHTMLRendered(page: Page, timeout: int = 30000):
check_duration_m_secs = 1000
max_checks = timeout / check_duration_m_secs
last_HTML_size = 0
check_counts = 1
count_stable_size_iterations = 0
min_stabe_size_iterations = 3
while check_counts <= max_checks:
check_counts += 1
html = await page.content()
currentHTMLSize = len(html);
if(last_HTML_size != 0 and currentHTMLSize == last_HTML_size):
count_stable_size_iterations += 1
else:
count_stable_size_iterations = 0 # reset the counter
if(count_stable_size_iterations >= min_stabe_size_iterations):
break
last_HTML_size = currentHTMLSize
await page.waitFor(check_duration_m_secs)
For me the { waitUntil: 'domcontentloaded' } is always my go to.
I found that networkidle doesnt work well...
I have a puppeteer script that inputs some text into a field, submits the query, and processes the results.
Currently, the script only processes 1 search term at a time, but I need it to be able to process an array of items consecutively.
I figured I would just put the code in a loop (see code below), however, it just types in all the items from the array at once into the field and doesn't execute the code block for each search term:
for (const search of searchTerms) {
await Promise.all([
page.type('input[name="q"]', 'in:spam ' + search + String.fromCharCode(13)),
page.waitForNavigation({
waitUntil: 'networkidle2'
})
]);
const count = await page.evaluate((sel) => {
return document.querySelectorAll(sel)[1].querySelectorAll('tr').length;
}, 'table[id^=":"]');
if (count > 0) {
const more = await page.$x('//span[contains(#class, "asa") and contains(#class, "bjy")]');
await more[1].click();
await page.waitFor(1250);
const markRead = await page.$x('//div[text()="Mark all as read"]');
await markRead[0].click();
const selectAll = await page.$x('//span[#role="checkbox"]');
await selectAll[1].click();
const move = await page.$x('//div[#act="8"]');
await move[0].click();
await page.waitFor(5000);
}
}
I tried using a recursion function from Nodejs Synchronous For each loop
I also tried using a function generator with yields, as well as promises and even tried the eachSeries function from the async package from this post Nodejs Puppeteer Wait to finish all code from loop
Nothing I tried was successful. Any help would be appreciated, thanks!
There is no way to visit two websites at same time with same tab. You can try it on your browser to make sure.
Jokes aside, if you want to search multiple items, you have to create a page or tab for that.
for (const search of searchTerms) {
const newTab = await browser.newPage()
// other modified code here
}
... wait that will still search one by one. But if you use a map with concurrency limit, it will work well.
We can use p-all for this.
const pAll = require('p-all');
const actions = []
for (const search of searchTerms) {
actions.push(async()=>{
const newTab = await browser.newPage()
// other modified code here
})
}
pAll(actions, {concurrency: 2}) // <-- set how many to search at once
So we are looping thru each term, and adding a new promise on the action list. Adding functions won't take much time. And then we can run the promise chain.
You will still need to modify the code above to have what you desire.
Peace!