Splunk Search

Rex extraction

redferrari
New Member

I have a field called "user", i'm trying to extract the username from the string and create a new field called extracted_user that I will later run against an LDAP filter to look up additional AD info.

user field examples:
Smith, John M. (jmsmith)(+)
Doe, Jane P. (jpdoe)(+)

I want to extract the username between the first set of parenthesis "jmsmith" and "jpdoe" respectively.

My current search:
index=network sourcetype=opsec app_rule_name="Track Uncategorized Content" user!=NULL
| rex field=user “((?.*))(“

Right now the search runs, but extracted_user field isn't created and the user field is unchanged. Any help would be greatly appreciated.

Tags (2)
0 Karma
1 Solution

cpetterborg
SplunkTrust
SplunkTrust

You need to escape the parentheses that are part of the string:

| rex field=user "\((?P<extracted_user>[^\(]+)\)\("

View solution in original post

gmchenry
Explorer

Try this:
| rex field=_raw "(?:()(?P\w+)"

I tested this at regex101.com and it seemed to do the trick.

0 Karma

cpetterborg
SplunkTrust
SplunkTrust

You need to escape the parentheses that are part of the string:

| rex field=user "\((?P<extracted_user>[^\(]+)\)\("

redferrari
New Member

Ohhh, thanks!

0 Karma

redferrari
New Member

| rex field=user “((?.*))(“

0 Karma
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