Splunk Search

How to extract a field using rex?

iamtrying
New Member

This is the string in the log

I 2019-05-23 18:22:38.984Z 7881 216 XObk7A6CU-I62gr3UIKfXQAAAAs 1@43465473@A WPB-Log: file=/users/aa/test.cls method=fetchdata ID=Qwe123

I want to extract a field marked as bold to build a table.
Please note that all strings are variable so the rex should be generic.

Thanks for the help!

0 Karma
1 Solution

dmarling
Builder

Assuming that data is always in the same place this should grab it:

| rex "\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}.\d{3}Z \d+ \d+ (?<fieldName>[^\s]+)"

You'll need to choose the field name you want and replace fieldName with whatever you want to label that field. Here's a link to regex 101 that shows it working on the single example you provided: https://regex101.com/r/TdkzcA/1

If this comment/answer was helpful, please up vote it. Thank you.

View solution in original post

0 Karma

somesoni2
Revered Legend

Give this a try (assuming the value you want to extract is 6th element from the start)

your base search
| rex "^(\S+\s+){5}(?<YourField>\S+)"
0 Karma

iamtrying
New Member

It worked too

0 Karma

dmarling
Builder

Assuming that data is always in the same place this should grab it:

| rex "\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}.\d{3}Z \d+ \d+ (?<fieldName>[^\s]+)"

You'll need to choose the field name you want and replace fieldName with whatever you want to label that field. Here's a link to regex 101 that shows it working on the single example you provided: https://regex101.com/r/TdkzcA/1

If this comment/answer was helpful, please up vote it. Thank you.
0 Karma
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