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Formatting Log Name with Regex

JibBgh
New Member

Hello. I am currently trying to do something with a list of logs that I have been given.

All of the logs have the same format:

/this/is/.../an_example_relevantInformationHere.2016-08-03.log

What I want to do is to use regex to search through the strings and to find the part that says relevantInformationHere and create a table with that as the header. Right now my rex looks like:

..|rex "an_example_(?\w+)."| table parameterName

It looks like it worked in the regex testers that I used, but I am not receiving the expected output in splunk. What am I doing wrong and is there a difference between the splunk regex and the regex on another site?

Thank you.

0 Karma
1 Solution

sundareshr
Legend

Try this

... | rex field=_raw "_\w+_(?<parameterName>\w+)\." | table parameterName

View solution in original post

0 Karma

javiergn
Super Champion

Assuming you are talking about the source field give this a go:

| rex field=source "(?<parameterName>[a-zA-Z]+)\.\d{4}-\d{2}-\d{2}\.\w+"

Keep in mind you can play with the following bit [a-zA-Z]+ to accept whatever symbols you might expect in your relevant information section. Also remember \w+ includes underscores.

Hope that helps

0 Karma

sundareshr
Legend

Try this

... | rex field=_raw "_\w+_(?<parameterName>\w+)\." | table parameterName
0 Karma

JibBgh
New Member

When I tried that, it ended up putting the raw string parameterName instead of the actual value it should be.

0 Karma

sundareshr
Legend

I just test this run anywhere sample and it works. Can you test this and let me know the results

| makeresults | eval x="/this/is/.../an_example_relevantInformationHere.2016-08-03.log" | rex field=x "_\w+_(?<parameterName>\w+)\." | table parameterName
0 Karma

JibBgh
New Member

That worked properly, however, will this work properly without hard coding the name?

0 Karma

sundareshr
Legend

Is the name of the file. As in the source? If it is, change the rex command to this and it should work

rex field=source "_\w+_(?<parameterName>\w+)\." 
0 Karma
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