How to extract a substring from a string using grep?

Question

linux

There is a line received by curl:

{"jsonrpc":"2.0","result":[{"groupid":"63","name":"1voda","internal":"0","flags":"0"}],"id":1}

How to get the value of the groupid key from it - i.e. the number 63?
Made through cut, but very cumbersome and ugly.

Answer 1

echo '"{"jsonrpc":"2.0","result":[{"groupid":"63","name":"1voda","internal":"0","flags":"0"}],"id":1}"' | cut -d\" -f11
:

Cumbersome?
Better like this:

echo '{"jsonrpc":"2.0","result":[{"groupid":"63","name":"1voda","internal":"0","flags":"0"}],"id":1}' | jq -r '.result[0].groupid'
:

PS In general, it's easier to work with a jrpc server as a jrpc client, from the same python. Yes, even if you do not use the jrpc client implementation. You can also return an array of results here.

Answer 2

For a collection

echo "{"jsonrpc":"2.0","result":[{"groupid":"63","name":"1voda","internal":"0","flags":"0"}],"id":1}" | grep -oP "(?<=groupid:)[0-9]*"

Answer 3

How to get the value of the groupid key from it - i.e. the number 63?

Examples for MYSTRING:
MYSTRING='{"jsonrpc":"2.0","result":[{"groupid":"63","name":"1voda","internal":"0","flags": "0"}],"id":1}'
awk
grep
jq
variable expansion
cut
echo $MYSTRING|cut -d\" -f 10

Answer 4

echo '{"jsonrpc":"2.0","result":[{"groupid":"63","name":"1voda","internal":"0","flags":"0"}] ,"id":1}' | grep -oP '(?<=groupid":")\d+'