Splunk Search

field extraction between brackets

indeed_2000
Motivator

I have log file like this:

A[1020/09/09] B[1013/09/09] C[05-07-00000000-000-A-B-C]

want to extract field of A, B, C.

1-How can I extract content between brackets [] ? as you see in each brackets have (dash or slash ...)
2-How can I extract fields as it could be single part "1020/09/09" or split like this "1020" "09" "09"

Thanks,

0 Karma

kamlesh_vaghela
SplunkTrust
SplunkTrust

@mehrdad_2000

You can try this also.

| makeresults 
| eval _raw=" A[1020/09/09] B[1013/09/09] C[05-07-00000000-000-A-B-C]" 
| rex field=_raw "A\[(?<A>[^\]]+)\]\sB\[(?<B>[^\]]+)\]\sC\[(?<C>[^\]]+)\]"

If you want to split values in multivalued or space separated then add below search

| eval A1=split(A,"/"),A2=replace(A,"/"," ")

if you want to get multi values in different fields then use below search

| eval x=mvindex(A1,0), y=mvindex(A1,1), z=mvindex(A1,2)

Thanks

0 Karma

FrankVl
Ultra Champion

I'd not suggest using .+, but simply use [^\]]+. For a single event like this, that reduces the number of steps needed to evaluate from 171 to just 21 as it completely removes the need for backtracking.
A\[(?<A>.+)\]\sB\[(?<B>.+)\]\sC\[(?<C>.+)\] https://regex101.com/r/7T5u9C/1
A\[(?<A>[^\]]+)\]\sB\[(?<B>[^\]]+)\]\sC\[(?<C>[^\]]+)\] https://regex101.com/r/AY9qew/1

Have a look at the debugger on how bad .+ behaves: https://regex101.com/r/7T5u9C/1/debugger

kamlesh_vaghela
SplunkTrust
SplunkTrust

Cool @FrankVl . Thanks for the regex optimization. You regex improved with many steps. 🙂
I have updated my answer with new one.

vnravikumar
Champion

Hi

Check this. if not, please specify your expected results.

| makeresults 
| eval test="A[1020/09/09] B[1013/09/09] C[05-07-00000000-000-A-B-C]" 
| eval temp=split(test," ") 
| rex field=temp "\[(?P<output>.+)\]"
0 Karma

FrankVl
Ultra Champion

Same here: don't use .+ if you don't have to. See my other comment for the reason why.

0 Karma
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