[🐛 Bug]: start_devtools() issues command to wrong TargetHandler

[victorvianna]

Description

Repro instructions: run this on 4.33.0

cdp, conn = webdriver.Chrome(service=service, options=options).start_devtools()
conn.execute(cdp.target.send_message_to_target(str(next(cdp.network.enable())), conn.session_id))

Expected: it works
Actual:

Exception: {'code': -32602, 'message': 'No session with given id'}

After adding various debug logs to selenium, chrome and chromedriver, I was able to verify the following:

• This in selenium triggers this in Chrome with this=Handler1, target_id="Target1" and out_session_id="Session1".
• But later when the Network.enable() command is issued, it arrives here with this=Handler2, target_id=std::nullopt, and session_id="Session1". Thus, failing this lookup

Possibly related: is it actually correct that start_devtools() arbitrarily attaches to the first handler returned by Target.getTargets() here? My understanding is these handlers map to different functionalities of the protocol, e.g. there is a a NetworkHandler responsible for Network.* commands.

Reproducible Code

See above

Debugging Logs

See above

[selenium-ci]

@victorvianna, thank you for creating this issue. We will troubleshoot it as soon as we can.

Selenium Triage Team: remember to follow the Triage Guide

[victorvianna]

+@p0deje as author of start_devtools(). But I'm starting to suspect the problem could be in Chrome, I asked in https://crbug.com/420658536

[diemol]

What happens if you try with Chrome 136?

[victorvianna]

I'm using M136 (I feel like I wrote M137 in the selenium bug template, but couldn't find the field to edit)

[victorvianna]

I was holding it wrong. Selenium uses flattened mode, so send_message_to_target should not be used. The event handler also needs to take 1 parameter, not 0. Here's the fixed snippet

cdp, conn = webdriver.Chrome(service=Service(), options=Options()).start_devtools()
conn.execute(cdp.network.enable())
conn.on(cdp.network.RequestWillBeSent, lambda e: print("got event"))

[github-actions]

This issue has been automatically locked since there has not been any recent activity since it was closed. Please open a new issue for related bugs.