Having a log file such as:
[DEBUG][2016-06-24 11:10:10,064][DataSourceImpl] - [line A...]
[DEBUG][2016-06-24 11:10:10,069][DataSourceImpl] - [line B...]
[DEBUG][2016-06-24 11:10:12,112][DataSourceImpl] - [line C...]
which is under tail -f real-time monitoring, is it possible to auto-insert (via a command we would pipe to the tail) "blank lines" after, let's say, 2 seconds of inactivity?
Expected result:
[DEBUG][2016-06-24 11:10:10,064][DataSourceImpl] - [line A...]
[DEBUG][2016-06-24 11:10:10,069][DataSourceImpl] - [line B...]
---
[DEBUG][2016-06-24 11:10:12,112][DataSourceImpl] - [line C...]
(because there is a gap of more than 2 seconds between 2 successive lines).
awk -F'[][\\- ,:]+' '1'
The above will split fields on ], [, -, ,, and :, so that each field is as described below:
[DEBUG][2016-06-24 11:10:10,064][DataSourceImpl] - [line A...]
22222 3333 44 55 66 77 88 999 ...
You can then concatenate some of the fields and use that to measure time difference:
tail -f input.log | awk -F'[][\\- ,:]+' '{ curr=$3$4$5$6$7$8$9 }
prev + 2000 < curr { print "" } # Print empty line if two seconds
# have passed since last record.
{ prev=curr } 1'