[SOLVED] Grep last occurrence word till end of line

eng_mohammedmostafa · 04-07-2020, 11:01 PM

Hi All,

Please, I need to grep last occurrence word till end of line.

Here is the file content:
[[{"configKey":"Parm1",{"configKey":"Parm2",{"configKey":"Parm3"]]

How to return only this please?
{"configKey":"Parm3"]]

Regards,
Mohamed

shruggy · 04-07-2020, 11:17 PM

Code:

grep -Po '.*Parm2",\K.*'

berndbausch · 04-08-2020, 12:48 AM

The text looks ill-formed. Where are the closing braces?

shruggy's expression only works if you know the string on the left of the last configkey. If this code is JSON, try a JSON tool like jq or pipe it through a pretty-printer like Python's json.tool. But again, it looks ill-formed.

sed instead of grep:

Code:

echo '[[{"configKey":"Parm1",{"configKey":"Parm2",{"configKey":"Parm3"]]' | sed 's/.*\({"configKey.*\)/\1/'

pan64 · 04-08-2020, 02:09 AM

yes, sed is better here.
If you want to use grep you need to be more explicit:

Code:

grep -o '{"configKey":"[^"]*"[]]*$'

This will work on the example you posted, but most probably will fail on a real json file.
you need to use jq/perl/python to handle it properly.

eng_mohammedmostafa · 04-08-2020, 10:30 AM

Thanks for your feedback

But let me clarify please that (Parm1,Parm2 and Parm3) are variables .. I just provided them as examples.
The only common word between all of them is: {"configKey":"

So, I need to grep last {"configKey":" till the end of the line.

TB0ne · 04-08-2020, 11:36 AM

Quote:

Originally Posted by eng_mohammedmostafa

Thanks for your feedback
But let me clarify please that (Parm1,Parm2 and Parm3) are variables .. I just provided them as examples. The only common word between all of them is: {"configKey":"

So, I need to grep last {"configKey":" till the end of the line.

Ok, so as you've been asked in the past, can you show us what YOU have done/tried to solve your problem?? Read the "Question Guidelines" link in my posting signature...there are lots of examples using sed and awk that you can find with a brief Google search, and a simple sed/grep can do this, if you tried. Given the input of:

Code:

[[{"configKey":"Parm1",{"configKey":"Parm2",{"configKey":"Parm3"]]
[[{"configKey":"Parm1",{"configKey":"Parm2",{"configKey":"Parm4"]]
[[{"configKey":"Parm1",{"configKey":"Parm2",{"configKey":"Parm5"]]
[[{"configKey":"Parm1",{"configKey":"Parm2",{"configKey":"Parm9"]]
[[{"configKey":"Parm1",{"configKey":"Parm2",{"configKey":"Parm8"]]
[[{"configKey":"Parm1",{"configKey":"Parm2",{"configKey":"Parm2"]]

...and using this:

Code:

sed 's/,/^M/g' t | grep configKey

...you get:

Code:

{"configKey":"Parm3"]]
{"configKey":"Parm4"]]
{"configKey":"Parm5"]]
{"configKey":"Parm9"]]
{"configKey":"Parm8"]]
{"configKey":"Parm2"]]

...which seems to be what you want, isn't it?? You never followed up the last time you asked people to write your scripts for you:
https://www.linuxquestions.org/quest...ge-4175670905/

pan64 · 04-08-2020, 12:29 PM

you can easily adjust the grep I posted

MadeInGermany · 04-08-2020, 12:49 PM

Quote:

Originally Posted by berndbausch

The text looks ill-formed. Where are the closing braces?
...
sed instead of grep:

Code:

echo '[[{"configKey":"Parm1",{"configKey":"Parm2",{"configKey":"Parm3"]]' | sed 's/.*\({"configKey.*\)/\1/'

You do not need to cover (cut and give back) the remainder of the line:

Code:

echo '[[{"configKey":"Parm1",{"configKey":"Parm2",{"configKey":"Parm3"]]' | sed 's/.*\({"configKey\)/\1/'

will save a few CPU cycles.

eng_mohammedmostafa · 04-08-2020, 02:33 PM

This one fulfilled the request
sed 's/.*\({"configKey.*\)/\1/'

Many thanks

crts · 04-08-2020, 05:22 PM

Maybe I am oversimplifying, but

Code:

sed 's/.*,//' testfile

As has already been pointed out, the text looks like some malformed JSON file. If the format is corrected the solutions may need to be adjusted.

TB0ne · 04-08-2020, 06:00 PM

Quote:

Originally Posted by crts

Maybe I am oversimplifying, but

Code:

sed 's/.*,//' testfile

As has already been pointed out, the text looks like some malformed JSON file. If the format is corrected the solutions may need to be adjusted.

Who knows? The OP didn't answer any questions about the input data, and showed no effort of their own to solve their problem.