We have developed some sort of proxy for a client's need. Incoming requests are processed and send it to the final destination.
We need to measure the transit time between us, which is concretely the time between the arrival log on our Apache and the tomcat log (juste before we send it to the destination).
These logs are on two separate files (apache httpd log and tomcat log). The target log lines have a common identifier.
188.8.131.52 - - [02/Dec/2019:15:29:09 +0000] "POST /myapplication HTTP/1.1" 200 266 aa137784-e33d-4474-ae1b-0b879779ca85 101284
2019-12-02T15: 29: 09.087Z, [http-nio-8080-exec-2], aa137784-e33d-4474-ae1b-0b879779ca85, OUTBOUND request sent