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best field extraction regex for custom log format

dominiquevocat
SplunkTrust
SplunkTrust

Hi,

i have a written DirXML driver that audits specific attributes that change and write syslog using log4j. The format i emply is always {attribute:nameOfAttribute} {qualified-src-dn:valueofqualifiedSrcDn} etc. So I am trying to generate a regex to take
any occurance of {x:y} and treat x as fieldname and y as value in field of name x.

I had no luck using the interactive log extractor. Also complicating things is that the DN has plenty of "dangerous" characters for a regex.

Any help is aprechiated. Oh the format i employ is inspired by XDAS. I can modify the format if it makes i easier but i figured using {} would make it easier.

Tags (1)
0 Karma

stephanbuys
Path Finder

Try: {([^:].+?):([^}].+?)}

$1 will be your key and $2 will be your value.

0 Karma

dominiquevocat
SplunkTrust
SplunkTrust

The regex works on my sample data see http://regexr.com?30mep however i get no fields in splunk when i use it as a inline regex. Is there a way in splunk 4.3 and up to do it inline?

0 Karma

dominiquevocat
SplunkTrust
SplunkTrust

ok, the second one seems to work nice enough. Thanks

0 Karma

gkanapathy
Splunk Employee
Splunk Employee

Don't do this in the interactive field extractor. You'll have to do it in manager or the config file. I don't the IFE can handle dynamic field names. The regex {(?<_KEY_1>[^:]*):(?<_VAL_1>[^}]*)} should also work.

0 Karma

dominiquevocat
SplunkTrust
SplunkTrust

also i might add i strive to have the value of $1 as the fieldname in splunk named as such and not as group named "1". Does that make sense?

0 Karma

dominiquevocat
SplunkTrust
SplunkTrust

Looks nice... i get
Invalid regex: no named extraction at position 0 (i.e., "{([^:].+?)..."). Expected "(?Ppattern)"

0 Karma
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