OTEL plugin: the header_type parameter is deprecated, please update your configuration to use propagation.extract and propagation.inject instead

[garciasdos]

Is there an existing issue for this?

• I have searched the existing issues

Kong version ($ kong version)

Kong 3.7.0

Current Behavior

When any service call reaches this plugin, I get a warning message:

kong-1  | 2024/06/13 11:39:50 [warn] 5363#0: *6481 [kong] init.lua:86 [opentelemetry] the header_type parameter is deprecated, please update your configuration to use propagation.extract and propagation.inject instead, client: 192.168.65.1

Here's my opentelemetry plugin configuration:

  - name: opentelemetry
    id: 9e7fdd24-d119-40b7-8e7c-75e8042fd59d
    protocols:
      - grpc
      - grpcs
    tags:
      - global-plugin
    enabled: true
    config:
      endpoint: $ENDPOINT
      resource_attributes:
        ...
      headers:
        api-key: $KEY

but header_type is not being modified elsewhere

Expected Behavior

When any service call reaches this plugin, I should not get a warning message if no custom configuration was made

Steps To Reproduce

1. Launch a kong 3.7 project
2. Add the opentelemetry OSS plugin
3. Do not modify the header_type attribute

Anything else?

No response

[StarlightIbuki]

A possible cause of the issue: are you using decK? The old default value "preserve" could trigger the warning.
@samugi Could you take a look?

[samugi]

There are indeed redundant warnings, we have proper logic during schema validation that prevent this from happening when the value used is the default, but the ones logged during header propagation setup did not have a check for that. I removed them and attached the PR. Thanks for reporting @garciasdos.