[Logging] Customize flagd logger format

[beeme1mr]

Overview

open-feature/flagd#322 introduced customizable log formats. It also set the default format to console where previously it was set to JSON. The OFO should continue to default to JSON but expose the log format options to Helm and the flag source config CR.

Requirements

• Add log format as an option in the flag source config CR
• Add a Helm configuration that set the default value cluster wide and default the value to json
• Update documentation in include information about the logger

[mowies]

Hey @beeme1mr !
I'd like to work on this :)

[mowies]

But i guess the integration into the flag source config CR is not fully possible yet, since the controller behind it is not implemented yet right?
I can just add the field to the flag source config CRD for now 🤷🏼

[beeme1mr]

Hey @james-milligan, could you please answer @mowies question?

[james-milligan]

@mowies adding this configuration to the controller is relatively straightforward as we can pass this configuration to the sidecar via an environment variable.
You would just need to extend the ToEnvVars method in /apis/core/v1alpha1/flagsourceconfiguration_types.go to include the FLAGD_LOG_FORMAT env var following the pattern of the existing configurations

[mowies]

Ahh ok! I went straight for the v1alpha2 API version and that file is basically empty :D

[james-milligan]

No problem, most / all of the logic is found in the v1alpha1 package which we use as our hub, we then use conversion functions to convert all later versions to the hub version