[processor/transform] Add support for parsing json log bodies

[lsampras]

Description:

• Adding support for getting nested values in json log bodies
• This allows us to read values that are nested in json and use them for operations

Link to tracking Issue: #14938

Testing:

tested with this config

processors:
    transform:
        logs:
          statements:
            - set(attributes["log_type"], json_body["log_type"])

Documentation:
None

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: lsampras / name: Sampras Lopes (121082c)

[github-actions]

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

[github-actions]

Closed as inactive. Feel free to reopen if this PR is still being worked on.

[TylerHelmuth]

@lsampras I missed this PR when it was first created, but I think the concept of "json_body" has potential. Are you still interested in this? If not I can work on it.

[lsampras]

@TylerHelmuth I had created this initial part to gather feedback, however ended up using it as the solution for my case (have put up a docker image here).

Not sure what is the aimed spec/design for this, I wonder if any of the work done here will be replaced by #9410.

Yeah won't mind if you wanna take over this, (I can also help if needed).