argo-rollouts metric provider plugin loggers do not respect logformat json #4408

Checklist:

• I've included steps to reproduce the bug.
• I've included the version of argo rollouts.

Describe the bug

The metrics provider plugin logs are defaulting to the text format, which is inconsistent with the controller logger when --logformat json is set.

I am assuming this is due to the go-plugin client requiring an hclog logger, and the argo-rollouts metrics plugin provider code not setting the Logger when creating a new go-plugin client

, thus all metrics plugin provider logs are defaulting to the text format.

Even when app/plugin code itself sets its logs as json for its own logger and when serving the go plugin, these are just logged as argo-rollouts 2025-08-18T09:53:56.003Z [DEBUG] plugin.my-plugin: {"env":"demo",...}.

To Reproduce

The easiest way to reproduce this is to enable any metrics provider plugin when configuring the controller https://github.com/argoproj/argo-helm/blob/main/charts/argo-rollouts/values.yaml#L232C3-L232C24.

Expected behavior

The logs are in the json log format instead of a mixed format when --logformat json is set.

Version

v1.8.3

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