[processor/redaction] apply redaction to log.body (#37239)

[karakayasemi]

Description

This update applies redaction rules to the log.body field by supporting multiple data types, including string, slices, maps, and nested maps. It applies key-based configurations consistently across all map structures.

• Key-Based Configurations: Applies redaction rules at all nesting levels.
• New Debug Attributes:
  • redaction.body.redacted.keys / redaction.body.redacted.count
  • redaction.body.masked.keys / redaction.body.masked.count
  • redaction.body.allowed.keys / redaction.body.allowed.count
  • redaction.body.ignored.count

Link to tracking issue

Fixes #37239

Testing & Refactoring

• Extended Tests: Log body redaction added to all existing cases + new tests for detailed body structure validation.
• Code Cleanup: Introduced helper methods for redaction, masking, allowing, and ignoring logic.
• Improved Readability: Renamed some const variables for clarity and consistency.

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: karakayasemi / name: Semih Serhat Karakaya (4ebc42c, 0e184c8)
• ✅ login: atoulme / name: Antoine Toulme (149f4ae)

[karakayasemi]

@dmitryax @mx-psi @TylerHelmuth @jpkrohling Any comment on the approach? I tried to keep the implementation as basic as possible. I can add a changelog and cover it with the tests if it seems good to go.

[github-actions]

This PR was marked stale due to lack of activity. It will be closed in 14 days.

[TylerHelmuth]

@karakayasemi please add some tests for this new functionality

[karakayasemi]

@TylerHelmuth I've added corresponding tests for string body redaction. When the body type is a map, I'm using the existing processAttrs method, which is already well-tested. Could you please take a look?

[gray-oni]

hey @karakayasemi the current implementation covers the situation when the Log's body is a string or one-level map value. However, if users use highly structured logs with nested map values (I'm one of these users🙂) it will not work (nested properties will be ignored and not redacted/masked). should we take into account the use-case of nested-structured logs body within the implementation? (otherwise this feature feels half-baked)

[karakayasemi]

Hey @gray-oni,
Thanks for your feedback and for taking an interest in the PR! 🙌

The current implementation processes map values similarly to attribute handling—it converts them to a string, applies redaction, and then sets the modified value back. You can check the implementation here.

From this perspective, it should work as expected for now. However, I agree that supporting nested map structures would be a good improvement. But, IMHO, since this would impact logs, metrics, and traces, I believe it would be better to track it as a separate issue rather than expand the scope of this PR.

What do you think?

[github-actions]

This PR was marked stale due to lack of activity. It will be closed in 14 days.

[karakayasemi]

@mx-psi @TylerHelmuth @dmitryax @evan-bradley @jpkrohling — Anything I can do to get attention on this PR? Appreciate your review when you get a chance!

[github-actions]

This PR was marked stale due to lack of activity. It will be closed in 14 days.

[mx-psi]

@dmitryax Since you started reviewing this, would you mind taking another look?

[atoulme]

Passes my review. @mx-psi @TylerHelmuth @dmitryax please review as codeowners.

[dmitryax]

Sorry for the delayed response. The PR LGTM