How do I get WWW::Mechanize::PhantomJS to wait until the JavaScript on the web page has finished executing?

Darth Ed has asked for the wisdom of the Perl Monks concerning the following question:

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Re: How do I get WWW::Mechanize::PhantomJS to wait until the JavaScript on the web page has finished executing? by LanX (Saint) on Aug 21, 2021 at 01:35 UTC
Browsers have no reliable event saying "JS has finished executing", because there might be a timer constantly executing functions or callbacks triggered by returning AJAX requests ... and so on. Note also that JS can run in parallel. So you have to tell Mechanize to wait for an DOM-element to appear which represent the state you consider "finished". When working with WWW::Mechanize::Firefox many years ago I used this Wait-until-an-element-appears approach. You have to see how this best translates to PhantomJS and your use case. Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply]
Re^2: How do I get WWW::Mechanize::PhantomJS to wait until the JavaScript on the web page has finished executing? by Darth Ed (Beadle) on Aug 21, 2021 at 07:13 UTC
So you have to tell Mechanize to wait for an DOM-element to appear which represent the state you consider "finished". Sure, I get that, but I haven't been able to figure out how to do that with WWW::Mechanize::PhantomJS. I don't see an `is_visible` method listed in the POD.... I'd be fine with just setting a timer for 3 seconds, but, again, I don't see how to do that either.	[reply] [d/l]
Re^3: How do I get WWW::Mechanize::PhantomJS to wait until the JavaScript on the web page has finished executing? by Corion (Patriarch) on Aug 21, 2021 at 12:04 UTC
As a third alternative, you can look for the corresponding code in the sister modules WWW::Mechanize::Firefox or WWW::Mechanize::Chrome and copy that into your code. Note that WWW::Mechanize::PhantomJS is not under development anymore. The program `phantomjs` also is not developped anymore.	[reply] [d/l]
Re^4: How do I get WWW::Mechanize::PhantomJS to wait until the JavaScript on the web page has finished executing? by Darth Ed (Beadle) on Aug 21, 2021 at 17:09 UTC
Re^5: How do I get WWW::Mechanize::PhantomJS to wait until the JavaScript on the web page has finished executing? by LanX (Saint) on Aug 21, 2021 at 19:00 UTC
Re^3: How do I get WWW::Mechanize::PhantomJS to wait until the JavaScript on the web page has finished executing? by LanX (Saint) on Aug 21, 2021 at 11:11 UTC
Using one of the selectors in WWW::Mechanize::PhantomJS to find a "finished" characteristic (DOM element or attribute or combination or ...) should return an empty result unless it exists. (See all EXTRACTION-METHODS) And even if this didn't work, you could `->eval` your own JS-code which does those checks in a loop for you and only returns after success. Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply] [d/l]
Re^3: How do I get WWW::Mechanize::PhantomJS to wait until the JavaScript on the web page has finished executing? by Corion (Patriarch) on Aug 21, 2021 at 07:39 UTC
Maybe just use sleep to wait for three seconds?	[reply]
Re^4: How do I get WWW::Mechanize::PhantomJS to wait until the JavaScript on the web page has finished executing? by Darth Ed (Beadle) on Aug 21, 2021 at 17:16 UTC
Re^5: How do I get WWW::Mechanize::PhantomJS to wait until the JavaScript on the web page has finished executing? (update) by LanX (Saint) on Aug 21, 2021 at 19:30 UTC
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