hack: prepare for strict golangci-lint in pull-verify-kubernetes

The long-term goal is that when "make verify" is invoked in pull job, it will
also run golangci-lint with the strict configuration and write an
$ARTIFACTS/golangci-lint-githubactions.log file with GitHub actions
annotations. How to get those published for the GitHub PR is open.

When "make verify" is invoked manually or in any other job, the stricter check
will be skipped. That works because "PR_NUMBER" is only set for pre-merge
jobs (https://github.com/kubernetes/test-infra/blob/master/prow/jobs.md#job-environment-variables).

Because strict linting is still new and might not be useful without a better
UI (= GitHub annotations), this PR does not fully enable the integration into
"make verify". Instead, the new verify-golangci-lint-pr.sh is excluded from it
and needs to be run in a separate job.

hack/make-rules/verify.sh

@@ -33,6 +33,7 @@ source "${KUBE_ROOT}/third_party/forked/shell2junit/sh2ju.sh"
 EXCLUDED_PATTERNS=(
   "verify-all.sh"                # this script calls the make rule and would cause a loop
   "verify-*-dockerized.sh"       # Don't run any scripts that intended to be run dockerized
+  "verify-golangci-lint-pr.sh"   # Don't run this as part of the block pull-kubernetes-verify yet. TODO(pohly): try this in a non-blocking job and then reconsider this.
   "verify-licenses.sh"           # runs in a separate job to monitor availability of the dependencies periodically
   )
 

hack/verify-golangci-lint-pr.sh

@@ -0,0 +1,37 @@
+#!/usr/bin/env bash
+
+# Copyright 2022 The Kubernetes Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This script checks a PR for the coding style for the Go language files using
+# golangci-lint. It does nothing when invoked as part of a normal "make
+# verify".
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+if [ ! "${PULL_NUMBER:-}" ]; then
+  echo 'Not testing anything because this is not a pull request.'
+  exit 0
+fi
+
+KUBE_ROOT=$(dirname "${BASH_SOURCE[0]}")/..
+
+# TODO (https://github.com/kubernetes/test-infra/issues/17056):
+# take this additional artifact and convert it to GitHub annotations
+# to make it easier to see these problems during a PR review.
+#
+# -g "${ARTIFACTS}/golangci-lint-githubactions.log"
+"${KUBE_ROOT}/hack/verify-golangci-lint.sh" -r "${PULL_BASE_SHA}" -s

hack/verify-golangci-lint.sh

@@ -26,6 +26,8 @@ Usage: $0 [-r <revision>|-a] [-s] [-c none|<config>] [-- <golangci-lint run flag
    -a: automatically select the common base of origin/master and HEAD
        as revision
    -s: select a strict configuration for new code
+   -g <github action file>: also write results with --out-format=github-actions
+       to a separate file
    -c <config|"none">: use the specified configuration or none instead of the default hack/golangci.yaml
    [packages]: check specific packages or directories instead of everything
 EOF
@@ -58,7 +60,7 @@ golangci_config="${KUBE_ROOT}/hack/golangci.yaml"
 base=
 strict=
 githubactions=
-while getopts "ar:sc:" o; do
+while getopts "ar:sg:c:" o; do
   case "${o}" in
     a)
       base="$(git merge-base origin/master HEAD)"
@@ -75,6 +77,9 @@ while getopts "ar:sc:" o; do
       golangci_config="${KUBE_ROOT}/hack/golangci-strict.yaml"
       strict=1
       ;;
+    g)
+      githubactions="${OPTARG}"
+      ;;
     c)
       if [ "${OPTARG}" = "none" ]; then
         golangci_config=""
@@ -131,19 +136,31 @@ popd >/dev/null
 cd "${KUBE_ROOT}"
 
 res=0
-if [[ "${#targets[@]}" -gt 0 ]]; then
+run () {
+  if [[ "${#targets[@]}" -gt 0 ]]; then
     echo "running ${golangci[*]} ${targets[*]}" >&2
     "${golangci[@]}" "${targets[@]}" >&2 || res=$?
-else
+  else
     echo "running ${golangci[*]} ./..." >&2
     "${golangci[@]}" ./... >&2 || res=$?
     for d in staging/src/k8s.io/*; do
-        MODPATH="staging/src/k8s.io/$(basename "${d}")"
-        echo "running ( cd ${KUBE_ROOT}/${MODPATH}; ${golangci[*]} --path-prefix ${MODPATH} ./... )"
-        pushd "${KUBE_ROOT}/${MODPATH}" >/dev/null
-            "${golangci[@]}" --path-prefix "${MODPATH}" ./... >&2 || res=$?
-        popd >/dev/null
+      MODPATH="staging/src/k8s.io/$(basename "${d}")"
+      echo "running ( cd ${KUBE_ROOT}/${MODPATH}; ${golangci[*]} --path-prefix ${MODPATH} ./... )"
+      pushd "${KUBE_ROOT}/${MODPATH}" >/dev/null
+        "${golangci[@]}" --path-prefix "${MODPATH}" ./... >&2 || res=$?
+      popd >/dev/null
     done
+  fi
+}
+# First run with normal output.
+run "${targets[@]}"
+
+# Then optionally do it again with github-actions as format.
+# Because golangci-lint caches results, this is faster than the
+# initial invocation.
+if [ "$githubactions" ]; then
+  golangci+=(--out-format=github-actions)
+  run "$${targets[@]}" >"$githubactions" 2>&1
 fi
 
 # print a message based on the result