How to extract particular value using regular expression?

[chetanhonnavile]

In the below event "status" key has the value either "1" or "0" . I am looking out to extract those "status" having the value "0" and put them in a field

please help me out in getting a regular expression for this.

2017-02-14 18:47:28.572 INFO  SomePlaceHolder-5 [.abc.def.nothingishere]  - string response: <200 OK,{"clips":[{"myid":"123456","historyid":"777-888-999","provider":"somecompany","status":1,"userType":1}]},{X-Backside-Transport=[OK OK], Connection=[Keep-Alive], Transfer-Encoding=[chunked], Content-Type=[application/json], X-Powered-By=[ARR/3.0,ASP.NET], Date=[Tue, 14 Feb 2017 18:47:28 GMT], X-Client-IP=[10.0.0.0.], X-Global-Transaction-ID=[9876543]}>

[cpetterborg]

Do you only want the ones with 0 as the value? This is the general solution:

... | rex "\"state\":(?P<status>\d),"

[chetanhonnavile]

yeah,looking for only status:0

well the query you provided gives me the same number of events combining both 0's and 1's.

if i am filtering it for only 0's then the event count will be too small.

[cpetterborg]

If you just want a count, you can do this:

 ... | rex "\"state\":(?P<status>\d)," | search status=0 | stats count 

or this:

 ... | rex "\"state\":(?P<status>0)," | where status=* | stats count

[richgalloway · Accepted solution]

Something like this, perhaps?

index=foo | regex "\"status\":0" | ...

[chetanhonnavile]

this is working...thanks!

now i am trying to put them in a field.

[chetanhonnavile]

well this solution looks like regular regex.

i am finding difficulty in understanding the 'rex' conventions used in splunk ,any good explanatory document at your end ?

[gvmorley]

Have a read of the section regarding 'named capture groups' here:

http://www.regular-expressions.info/named.html

This should be a good starting point to see how the rex command (not the regex command), can be used to create field / value pairs.

Building on the great answers above, think of it like this.

Find the part of your string which you want to match, then wrap it in brackets.

So if you wanted to find the digit after "status": you could write:

"\"status\":(\d)"

Now if you want to give that a field name (lets call it 'status_value') using rex, you could do:

"\"status\":(?<status_value>\d)"

In Splunk, you should now have a field called 'status_value' containing the digit from your event.

But the http://www.regular-expressions.info site is a great place to read up on regex in general.

[DalJeanis]

Put precisely WHAT in a field?