extract a string after a pattern

Question

I want to extract the numbers following client_id and id and pair up client_id and id in each line.

For example, for the following lines of log,

User(cli         


        

Answer 1

I would prefer awk for this, but if you were wondering how to do this with sed, here's one way that works with GNU sed.

parse.sed

/client_id/ {
  :a
  s/(client_id:([0-9]+))[^(]+\(id:([0-9]+)([^\n]+)(.*)/\1 \4\5\n\2 \3/
  ta
  s/^[^\n]+\n//
}

Run it like this:

sed -rf parse.sed infile

Or as a one-liner:

Output:

03 204
03 491
03 29

04 209
04 301

05 20

Explanation:

The idea is to repeatedly match client_id:([0-9]+) and id:([0-9]+) pairs and put them at the end of pattern space. On each pass the id:([0-9]+) is removed.

The final replace removes left-overs from the loop.