[rb] Adding method to send DevTools commands to Chrome and a helper method to enable downloads on headless Chrome.

[pulkitsharma07]

For: #5159

Files can now be downloaded in headless mode after setting the download directory's path using the #download_path= helper.

Working fine with Chrome 65 (chromedriver 2.36). For earlier versions of Chrome/chromedriver I was facing crashes when downloading files in headless mode.

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[luke-hill]

This logic can be used using a wait.until command much cleaner, and with more control. If you wait for the temporary file not to be there (It's hard to check but I "think" I may have mentioned this before.

[lmtierney]

After talking with the chromedriver team, the send_command will be moved to a w3c-compliant protocol extension endpoint (https://w3c.github.io/webdriver/webdriver-spec.html#protocol-extensions). We may want to hold off on this PR until the change.

See the issue raised in the chromium bugtracker: https://bugs.chromium.org/p/chromedriver/issues/detail?id=2307

[aasimali]

@pulkitsharma07

Files can now be downloaded in headless mode after setting the download directory's path using the #download_path= helper.

How Can I do that? Can you please tell me the steps? I use Ubuntu

[p0deje]

I don't know how I missed that PR at all 😕 The proposed changes were actually implemented in f77d2f9, so users can use driver.download_path = '/home'.

Sorry if this PR was a waste of your time, I somehow missed it completely. Is there anything else we need to take from here?

[SergeyPirogov]

Hello, maybe someone know how to send DevTools command?

I am able to use

browser.defineCustomCommand("sendCommand", new CommandInfo("/session/:sessionId/goog/cdp/execute", POST));

Object result = browser.sendCommand("Debugger.enable", new HashMap<>());

but I can not subscribe to event:

Object execute = browser.sendCommand("Debugger.scriptParsed", new HashMap<>());