Log level in the extension is not configurable

[ialidzhikov]

How to categorize this issue?

/area ops-productivity usability
/kind bug
/priority 3
/platform aws

What happened:
I don't see an option/flag how I can configure the log level in the extension:

$ docker run eu.gcr.io/gardener-project/gardener/extensions/provider-aws:v1.30.0 --help
Usage:
  provider-aws-controller-manager [flags]

Flags:
      --backupbucket-max-concurrent-reconciles int     The maximum number of concurrent reconciliations. (default 5)
      --backupentry-max-concurrent-reconciles int      The maximum number of concurrent reconciliations. (default 5)
      --bastion-max-concurrent-reconciles int          The maximum number of concurrent reconciliations. (default 5)
      --config-file string                             path to the controller manager configuration file
      --controlplane-max-concurrent-reconciles int     The maximum number of concurrent reconciliations. (default 5)
      --csimigration-max-concurrent-reconciles int     The maximum number of concurrent reconciliations. (default 5)
      --disable-controllers strings                    List of controllers to disable [backupbucket_controller bastion_controller controlplane_controller infrastructure_controller healthcheck_controller backupentry_controller csimigration_controller dnsrecord_controller worker_controller]
      --disable-webhooks strings                       List of webhooks to disable
      --dnsrecord-max-concurrent-reconciles int        The maximum number of concurrent reconciliations. (default 5)
      --dnsrecord-provider-client-burst int            The client burst for provider operations. (default 5)
      --dnsrecord-provider-client-qps float            The client QPS for provider operations. (default 1)
      --healthcheck-max-concurrent-reconciles int      The maximum number of concurrent reconciliations. (default 5)
  -h, --help                                           help for provider-aws-controller-manager
      --ignore-operation-annotation                    Ignore the operation annotation or not.
      --infrastructure-max-concurrent-reconciles int   The maximum number of concurrent reconciliations. (default 5)
      --kubeconfig string                              Paths to a kubeconfig. Only required if out-of-cluster.
      --leader-election                                Whether to use leader election or not when running this controller manager. (default true)
      --leader-election-id string                      The leader election id to use. (default "provider-aws-leader-election")
      --leader-election-namespace string               The namespace to do leader election in.
      --leader-election-resource-lock string           Which resource type to use for leader election. Supported options are 'endpoints', 'configmaps', 'leases', 'endpointsleases' and 'configmapsleases'. (default "leases")
      --master string                                  The address of the Kubernetes API server. Overrides any value in kubeconfig. Only required if out-of-cluster.
      --webhook-config-cert-dir string                 The directory that contains the webhook server key and certificate. (default "/tmp/gardener-extensions-cert")
      --webhook-config-mode string                     The webhook mode - either 'url' (when running outside the cluster) or 'service' (when running inside the cluster).
      --webhook-config-namespace string                The webhook config namespace for 'service' mode.
      --webhook-config-server-host string              The webhook server host.
      --webhook-config-server-port int                 The webhook server port. (default 443)
      --webhook-config-service-port int                The service port that exposes the webhook server.  If not specified it will fallback to the webhook server port.
      --webhook-config-url string                      The webhook URL when running outside of the cluster it is serving.
      --worker-deploy-crds                             Deploy the required worker CRDs. (default true)
      --worker-max-concurrent-reconciles int           The maximum number of concurrent reconciliations. (default 5)

For example the terraformer package logs with .V(1) in several places - for more details see gardener/gardener#4978. Currently there is no way to enable this logging.

What you expected to happen:
To have an option/flag about the log level.

How to reproduce it (as minimally and precisely as possible):
See above.

Anything else we need to know?:
This issue is not only applicable to provider-aws but I think it is applicable also for all of other provider extensions (at least the ones under github.com/gardener).

Environment:

• Gardener version (if relevant):
• Extension version:
• Kubernetes version (use kubectl version):
• Cloud provider or hardware configuration:
• Others:

[timebertt]

I hope that we can tackle this in one go, once we refactored all gardener components to zap/logr (part of gardener/gardener#4251). Then we can probably introduce some common flags, that will be used in all gardener components and extensions alike.
Also, ref gardener/gardener#4803 (comment)