OpenTelemetry.Exporter.Geneva: Compatibility with Fluent Bit

[dceravigupta]

Design discussion issue #
Currently, Traces and Logs emitted by OpenTelemetry.Exporter.Geneva package in Forward protocol format are not compatible with Fluent Bit's forward input plugin (tried with fluent-bit v3.0.6) and it fails to process those events with the following error:

where -8 error code means FLB_EVENT_DECODER_ERROR_WRONG_TIMESTAMP_TYPE

Changes

To make it compatible, as part of this PR, I applied the same strategy which Fluent Bit uses as part of forward output plugin where it has capability to send timestamp in the form of integer.

After applying the change, I was able to validate both Traces and Logs working e2e with Fluent Bit.

fluent-bit -i forward -p unix_path=./fluentbit.socket -o stdout =p match=* -v

Please provide a brief description of the changes here.

Merge requirement checklist

• CONTRIBUTING guidelines followed (license requirements, nullable enabled, static analysis, etc.)
• Unit tests added/updated
• Appropriate CHANGELOG.md files updated for non-trivial changes
• Changes in public API reviewed (if applicable)

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: dceravigupta / name: Ravi Gupta (c4b86e8, 3b582d8)

[xiang17]

What is the name and version of this "latest Fluent Bit's forward input plugin"? Can you give a link?

If the existing exporter and fluentd has been working and this new version is breaking. Would it be more appropriate to apply a fix in this new version?

[dceravigupta]

@xiang17 I have updated the post to include the fluent bit version I have tried i.e. fluent-bit v3.0.6.
https://docs.fluentbit.io/manual/dev-3.0/pipeline/inputs/forward

Before making this change, I also looked at fluent bit code base as well and the code on the fluent bit is the same since it was first written, hence feel it is not a regression and existing exporter never worked with fluent bit.

fluent/fluent-bit@9aa10d2

[xiang17]

Can you sign the EasyCLA?

[dceravigupta]

@xiang17 EasyCLA done.

[dceravigupta]

@xiang17 wondering whom all I need to get this PR approved?