Defining nested Tail-based sampling policies in OpenTelemetry Collector

[rahulgupta92]

When performing tail-based sampling with various services, there is a normally a need to sample traces based on a combination of policies like latency/string attribute exclusion/error status in spans etc. These conditions can be defined using and / or conditions.

For example: Let's say we need to build tail-based sampling policies for services A and B based on below conditions:

Policy 1 - For service A, sampling is done either on the string attribute should_sample as yes or on the latency>3000 ms.

(
  (Service == A) 
    AND
  ((latency > 3000ms) OR (string_attribute 'should_sample' == 'yes'))
)

Policy 2 - For service B , sampling is done either on the string attribute should_sample as no or (latency>4000ms and containing an error status code).

(
  (Service = B) 
    AND
  (
    ((latency > 4000) AND (status_code = ERROR))
      OR
     (string_attribute 'should_sample' == 'no')
  )
) 

I am unable to implement these policies using and policies.

Is it currently possible to implement this using the existing policies in the OpenTelemetry Collector config? Any suggestions/alternatives to try?

[jpkrohling]

And's are supported, Or's aren't. I believe @mottibec talked about Or's in the past, but I don't remember from the top of my head why we don't have them.

[mottibec]

The processor or's between all policies so for your use case you can have 2 separate policies one for latency and one for string attribute and you will get the same result.

[github-actions]

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[jpkrohling]

I'm closing this, as I believe this has been addressed. If that's not the case, let me know and I'll reopen this.