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Does transforms.conf support a regex group based rerouting?

paimonsoror
Builder

Hi all;

I am trying to build some logic for a docker/k8s integration that we are doing through fluentd. Basically we are testing one avenue of this integration utilizing fluentd -> splunk. One of the things we want to be able to do, is to leverage a field in the json payload called 'namespace' to separate the data into its own index. Right now, here is the setup of my inputs.conf

[tcp:1520]
connection_host = dns
index = app_cpceng
sourcetype = fluentd_json
acceptFrom = xx.xx.xx.xx

Now i know utilizing transforms we can do something like this:

[routemyhosttomynewindex]
SOURCE_KEY = MetaData:Host
REGEX = myhost
DEST_KEY = MetaData:Index
FORMAT = mynewindex

where in this example it reroutes the data to an alertnate index based on the hostname, but is it possible for me to do something like this:

[routemyhosttomynewindex]
SOURCE_KEY = MetaData:Raw (not sure if that is the correct meta name)
REGEX = \"namespace\":\"(\w+)\"
DEST_KEY = MetaData:Index
FORMAT = app_cpceng_$1

A very crude example above, but hopefully it illustrates what I am looking for.

0 Karma
1 Solution

somesoni2
Revered Legend

The default SOURCE_KEY is _raw so, just exclude that in your transforms.conf stanza, ensure regex is correct and it should work fine.
Reference, (REGEX per your need)
https://answers.splunk.com/answers/246672/how-can-i-override-an-index-name-based-on-sourcety.html

View solution in original post

0 Karma

somesoni2
Revered Legend

The default SOURCE_KEY is _raw so, just exclude that in your transforms.conf stanza, ensure regex is correct and it should work fine.
Reference, (REGEX per your need)
https://answers.splunk.com/answers/246672/how-can-i-override-an-index-name-based-on-sourcety.html

0 Karma

paimonsoror
Builder

Good to know, thanks for the info. One of my curiosities was if I could use regex group captures within the FORMAT field, but based on : https://answers.splunk.com/answers/326378/can-i-do-named-capture-in-transformsconf-format-ip.html it looks like I can, so i think my question is answered 🙂

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sbbadri
Motivator
0 Karma
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