#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?m).*(?<=GET )([^ ]*).*"
Local $sString = "00.00.00.00 - - [23/Mar/2020:16:23:04 +0000] "GET /foo/bar/uri.js?id=123 HTTP/1.1" 200 19165 "https://nginx.com/foo/bar" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.132 Safari/537.36" "00.00.00.00" 0.000" & @CRLF & _
"" & @CRLF & _
"00.00.00.00 - - [23/Mar/2020:16:23:04 +0000] "GET /foo/bar/uri HTTP/1.1" 200 19165 "https://nginx.com/foo/bar" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.132 Safari/537.36" "00.00.00.00" 0.000" & @CRLF & _
"" & @CRLF & _
"00.00.00.00 - - [23/Mar/2020:16:23:04 +0000] "GET /foo/bar/uri.png HTTP/1.1" 200 19165 "https://nginx.com/foo/bar" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.132 Safari/537.36" "00.00.00.00" 0.000"
Local $sSubst = "$1"
Local $sResult = StringRegExpReplace($sString, $sRegex, $sSubst)
MsgBox($MB_SYSTEMMODAL, "Result", $sResult)
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm