topic Postprocess chaining possible in simple XML? in Dashboards & Visualizations

Postprocess chaining possible in simple XML?

koprai — Thu, 02 Jul 2015 21:45:01 GMT

It is great the Splunk 6.2 allows multiple base searches. However I was wondering if postprocess chaining is possible.. That is a post process search is a base search for another post process search. The following is a cooked up dashboard XML that will illustrate what i am trying. I am not getting intended results. Not sure if it is a supported feature

<dashboard>
  <label>TempPostProcessChaining</label>
    <search id="baseSearch">
      <query>|stats count as dummy</query>
    </search>
  <row>
    <panel>
      <title>First Post Process Result</title>
      <table>
        <search base="baseSearch" id="firstPostProcess">
          <query>eval a=dummy+1 | fields *</query>
        </search>
      </table>
    </panel>
  </row>
    <row>
    <panel>
      <title>Second Post Process Result</title>
      <table>
        <search base="firstPostProcess">
          <query>eval b=a+1 | fields *</query>
        </search>
      </table>
    </panel>
  </row>
</dashboard>

Re: Postprocess chaining possible in simple XML?

martin_mueller — Thu, 02 Jul 2015 22:31:01 GMT

I'd say no.

The observed behaviour is similar to the old AdvancedXML PostProcess Module - while you could have multiple post processes underneath each other, one would override the other so you would always have base search | post process, never base search | post process 1 | post process 2. You can see this more clearly if you add | eval c = dummy + 10 to your second post process - it is applied, but the first post process is skipped.
The docs aren't terribly clear on this, but they do say "Post-process searches: A search that further modifies results from a base search." Taking that literally, a post process will always modify the base search... exactly what we're observing here.

http://docs.splunk.com/Documentation/Splunk/6.2.3/Viz/PanelreferenceforSimplifiedXML