feat(logging): migration to structure logging for main.go, pkg/ & internal/ folders

[dmpe]

What this PR does / why we need it:

/wg structured-logging
/area logging
/priority important-longterm
/kind cleanup
/cc @kubernetes/wg-structured-logging-reviews

How does this change affect the cardinality of KSM: (increases, decreases or does not change cardinality)

does not change cardinality

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):

part 1 of adding JSON support #1485, i.e. with this PR we introduce structure logging, by following the associated KEP https://github.com/kubernetes/community/blob/master/contributors/devel/sig-instrumentation/migration-to-structured-logging.md

[k8s-ci-robot]

@dmpe: The label(s) area/logging cannot be applied, because the repository doesn't have them.

In response to this:

What this PR does / why we need it:

/wg structured-logging
/area logging
/priority important-longterm
/kind cleanup
/cc @kubernetes/wg-structured-logging-reviews

How does this change affect the cardinality of KSM: (increases, decreases or does not change cardinality)

does not change cardinality

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):

part 1 of adding JSON support #1485, i.e. with this PR we introduce structure logging, by following the associated KEP https://github.com/kubernetes/community/blob/master/contributors/devel/sig-instrumentation/migration-to-structured-logging.md

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

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[dmpe]

I have tested this locally via e2e tests and it did not fail :)

When starting kube state metrics before my PR:

 ./kube-state-metrics 
I0813 14:05:15.320475   51084 server.go:93] Using default resources
I0813 14:05:15.322843   51084 types.go:136] Using all namespace
I0813 14:05:15.322881   51084 server.go:122] Metric allow-denylisting: Excluding the following lists that were on denylist: 
W0813 14:05:15.322905   51084 client_config.go:617] Neither --kubeconfig nor --master was specified.  Using the inClusterConfig.  This might not work.
W0813 14:05:15.322917   51084 client_config.go:622] error creating inClusterConfig, falling back to default config: unable to load in-cluster configuration, KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT must be defined
F0813 14:05:15.324143   51084 main.go:65] Failed to run kube-state-metrics: failed to create client: invalid configuration: no configuration has been provided, try setting KUBERNETES_MASTER environment variable
goroutine 1 [running]:
k8s.io/klog/v2.stacks(0x1)
	/home/jm/go/pkg/mod/k8s.io/klog/[email protected]/klog.go:860 +0x8a
k8s.io/klog/v2.(*loggingT).output(0x265b260, 0x3, 0x0, 0xc000421960, 0x1, {0x1e675c7?, 0x1?}, 0x265c460?, 0x0)
	/home/jm/go/pkg/mod/k8s.io/klog/[email protected]/klog.go:825 +0x686
k8s.io/klog/v2.(*loggingT).printfDepth(0x265b260, 0x0?, 0x0, {0x0, 0x0}, 0x7ffa5af073c0?, {0x18a8a12, 0x24}, {0xc0003ba8c0, 0x1, ...})
	/home/jm/go/pkg/mod/k8s.io/klog/[email protected]/klog.go:630 +0x1f2
k8s.io/klog/v2.(*loggingT).printf(...)
	/home/jm/go/pkg/mod/k8s.io/klog/[email protected]/klog.go:612
k8s.io/klog/v2.Fatalf(...)
	/home/jm/go/pkg/mod/k8s.io/klog/[email protected]/klog.go:1516
main.main()
	/home/jm/Documents/kube-state-metrics/main.go:65 +0x514

And after my proposed changes.

./kube-state-metrics 
I0813 14:08:53.765129   51528 server.go:93] "Used default resources"
I0813 14:08:53.765297   51528 types.go:136] "Using all namespace"
I0813 14:08:53.765314   51528 server.go:122] "Metric allow-denylisting" allowDenyStatus="Excluding the following lists that were on denylist: "
W0813 14:08:53.765342   51528 client_config.go:617] Neither --kubeconfig nor --master was specified.  Using the inClusterConfig.  This might not work.
W0813 14:08:53.765351   51528 client_config.go:622] error creating inClusterConfig, falling back to default config: unable to load in-cluster configuration, KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT must be defined
E0813 14:08:53.765443   51528 main.go:67] "Failed to run kube-state-metrics" err="failed to create client: invalid configuration: no configuration has been provided, try setting KUBERNETES_MASTER environment variable"

[mrueg]

Thanks!
/lgtm

/hold
for @dgrisonnet @fpetkovski to review.

[fpetkovski]

Is this because we don't have a way to log warn messages with structure logging?

[mrueg]

Yes, that does not exist there. See also: kubernetes/klog#184

[fpetkovski]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dmpe, fpetkovski, mrueg

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Needs approval from an approver in each of these files:

• OWNERS [fpetkovski,mrueg]

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[mrueg]

/hold cancel