Run some JS in Chrome from the command line and get the return value. Useful for scrapers that require JS and perhaps a session that's tricky to set up otherwise.

_USAGE.md

This AppleScript opens a page in Chrome (where you presumably have a logged-in session if required), opens the passed-in URL, runs the passed-in JavaScript and returns the JS return value.

Waits for 1 second for the page to load before executing the JS. Optionally, pass in a third argument with the number of seconds to wait.

Examples:

osascript js_in_chrome.scpt "http://google.com" "document.title"

# When logged in.
osascript js_in_chrome.scpt "http://search.ancestry.com/Browse/view.aspx?dbid=1670&path=1930.Spring.160V.1" "szImageURL"

# Custom wait.
osascript js_in_chrome.scpt "http://google.com" "document.title" 10

js_in_chrome.scpt

on run argv
	set theURL to item 1 of argv
	set theJS to item 2 of argv
	if length of argv > 2 then
		set theDelay to item 3 of argv
	else
		set theDelay to 1
	end if
	
	tell application "Google Chrome"
		tell window 1 to make new tab with properties {URL:theURL}
		delay theDelay -- Wait for page to load.
		set theResult to execute window 1's active tab javascript theJS
		delete tab (active tab index of window 1) of window 1
		if theResult is not missing value then
			theResult
		end if
	end tell
end run