puller: small refactor

[lidezhu]

What problem does this PR solve?

Issue Number: close #xxx

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test
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Questions

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[ti-chi-bot]

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[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: asddongmen

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-02-15 02:44:53.627156444 +0000 UTC m=+670136.023378501: ☑️ agreed by asddongmen.