Hello I am trying to use the ELK stack for error diagnosis with some testing output logs. I have a log structured as follows.
DateTime MessageType MessageOrigin Message
2021-10-28T00:11:16.385Z INFO fmwk.bll.base.task Received signal KILL
The message type defines whether the message is an error, debug, info etc. What I am trying to do is get the 20 or so lines immediately preceding and following when an error message is found. I know I can't get the line number from the original log file, so I have just been using the log.offset which is fine since it doesn't have to be exactly 20 lines. I can filter by messageType and get the offsets of the error messages fairly easily but I don't know how to then get a the group of messages around those offsets.
So basically what I would like is to get the offset of an error message and then check for all messages in a +/- 4000ish range from it to get the context of the error message. Is there a way to chain queries together like that in KQL where the output of one query becomes the input of another?