Question: access elements in iframe

Hi Andrea, I’d like to be able to access elements contained within an iframe. It doesn’t look like this is possible using chrome-remote-interface atm however it is possible using selenium/chromedriver, and of course within chrome it’s possible to change the frame in the devtools.

My questions are:

• did I miss something - is it already possible in chrome-remote-interface?
• have you looked into this before? and if so do you know much about how chromedriver has implemented this feature?
• is it something that you might want to add to chrome-remote-interface?
• do you know of any alternative ways of achieving the objective? I need to find an input element inside an iframe and set the value.

I put together a prototype to demonstrate how you can find elements inside an iframe using selenium/chromedriver (nb python implementation):

• https://github.com/ilanc/iframe-chrome-remote-interface

The code does the following:

• navigates to https://ilanc.github.io/iframe-chrome-remote-interface/iframe.html
• finds an element ‘#findme’ inside the iframe and logs the innerText (i.e. document.querySelector('#findme').innerText)

I’ve started looking into the chromedriver source but have not yet figured out what they’re doing:

• window_commands.cc - look for ExecuteSwitchToFrame
• session.cc - look for SwitchToSubFrame
• log of devtools and chromedriver commands executed by iframe prototype
• it doesn’t look like there’s anything in the devtools protocol that allows iframe switching

[paulirish]

@jsoverson It’s possible that chrome is using Site Isolation aka OOPIF (out of process iframes) for this jsbin iframe. In that case, the iframe is a brand new target.

Hypothetically you can disable OOPIF with -disable-features=IsolateOrigins,site-per-process but I haven’t verified this still works. If you can easily disable it, then the child frames should exist as you expect.

[jsoverson]

Thanks @paulirish, --disable-features=IsolateOrigins,site-per-process gives me the behavior I was expecting. I was banging my head against that for quite a long time, a warning or notice on Page.getFrameTree() may be worthwhile in order to save people the headache in the future.

Thanks again 🙂