hack: integrate logcheck into golangci-lint

Running logcheck as part of golangci-lint has several advantages:
- faster checking because finding files and parsing is shared
  with other linters
- gets rid of the complex and buggy
  hack/verify-structured-logging.sh (kubernetes#106746)
- support for // nolint:logcheck
- works with Go 1.18

Replay of 17e3c55

.golangci.yaml

@@ -21,10 +21,17 @@ linters:
   # - structcheck
   # - varcheck
     - ineffassign
+    - logcheck
     - staticcheck
     - unused
 
 linters-settings: # please keep this alphabetized
+  custom:
+    logcheck:
+      # Installed there by hack/verify-golangci-lint.sh.
+      path: _output/local/bin/logcheck.so
+      description: structured logging checker
+      original-url: k8s.io/klog/hack/tools
   staticcheck:
     go: "1.17"
     checks: [

hack/logcheck.conf

@@ -0,0 +1,22 @@
+# This file contains regular expressions that are matched against <pkg>/<file>,
+# for example k8s.io/cmd/kube-scheduler/app/config/config.go.
+#
+# By default, structured logging call parameters are checked, but usage of
+# those calls is not required. That is changed on a per-file basis.
+#
+# Remember to clean the golangci-lint cache when changing the configuration and
+# running the verify-golangci-lint.sh script multiple times, otherwise
+# golangci-lint will report stale results:
+#    _output/local/bin/golangci-lint cache clean
+
+# At this point we don't enforce the usage structured logging calls except in
+# those packages that were migrated. This disables the check for other files.
+-structured .*
+
+# Now enable it again for migrated packages.
+structured k8s.io/kubernetes/cmd/kube-proxy/.*
+structured k8s.io/kubernetes/cmd/kube-scheduler/.*
+structured k8s.io/kubernetes/cmd/kubelet/.*
+structured k8s.io/kubernetes/pkg/kubelet/.*
+structured k8s.io/kubernetes/pkg/proxy/.*
+structured k8s.io/kubernetes/pkg/scheduler/.*

hack/tools/go.mod

@@ -11,6 +11,6 @@ require (
 	github.com/google/go-flow-levee v0.1.5
 	gotest.tools/gotestsum v1.6.4
 	honnef.co/go/tools v0.2.2
-	k8s.io/klog/hack/tools v0.0.0-20210917071902-331d2323a192
+	k8s.io/klog/hack/tools v0.0.0-20220321081409-5b4c326b9f57
 	sigs.k8s.io/zeitgeist v0.2.0
 )

hack/verify-golangci-lint.sh

@@ -36,14 +36,25 @@ PATH="${GOBIN}:${PATH}"
 export GO111MODULE=on
 
 # Install golangci-lint
-echo 'installing golangci-lint '
+echo "installing golangci-lint and logcheck plugin from hack/tools into ${GOBIN}"
 pushd "${KUBE_ROOT}/hack/tools" >/dev/null
   go install github.com/golangci/golangci-lint/cmd/golangci-lint
+  go build -o "${GOBIN}/logcheck.so" -buildmode=plugin k8s.io/klog/hack/tools/logcheck/plugin
 popd >/dev/null
 
 cd "${KUBE_ROOT}"
 
-# The config is in ${KUBE_ROOT}/.golangci.yaml
+# The config is in ${KUBE_ROOT}/.golangci.yaml where it will be found
+# even when golangci-lint is invoked in a sub-directory.
+#
+# The logcheck plugin currently has to be configured via env variables
+# (https://github.com/golangci/golangci-lint/issues/1512).
+#
+# Remember to clean the golangci-lint cache when changing
+# the configuration and running this script multiple times,
+# otherwise golangci-lint will report stale results:
+# _output/local/bin/golangci-lint cache clean
+export LOGCHECK_CONFIG="${KUBE_ROOT}/hack/logcheck.conf"
 echo 'running golangci-lint ' >&2
 res=0
 if [[ "$#" -gt 0 ]]; then