[Bug] TopN Processor Fails to Fetch Schema from Write Request

[hanahmily]

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• I had searched in the issues and found no similar issues.

Apache SkyWalking Component

BanyanDB (apache/skywalking-banyandb)

What happened

There seems to be a bug introduced as a result of fixing issue #13480. The TopN processor currently does not support fetching the schema from the write request, which affects its functionality.

What you expected to happen

The TopN processor should successfully fetch the schema from the write request, allowing it to function as intended.

How to reproduce

1. Attempt to use the TopN processor after implementing the fix for issue [Feature] Remove column index based bulk write, use column name instead. #13480.
2. Observe the behavior "{"level":"error","module":"MEASURE","error":"tag is not defined","time":"2026-01-05T03:10:02Z","message":"fail to match criteria"}"

Anything else

No response

Are you willing to submit a pull request to fix on your own?

• Yes I am willing to submit a pull request on my own!

Code of Conduct

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