Add update/add-license-header makefile target

Signed-off-by: torredil <torredil@amazon.com>

Makefile

@@ -93,7 +93,7 @@ test/coverage:
 tools: bin/aws bin/ct bin/eksctl bin/ginkgo bin/golangci-lint bin/gomplate bin/helm bin/kops bin/kubetest2 bin/mockgen bin/shfmt
 
 .PHONY: update
-update: update/gofmt update/kustomize update/mockgen update/gomod update/shfmt
+update: update/gofmt update/kustomize update/mockgen update/gomod update/shfmt update/generate-license-header
 	@echo "All updates succeeded!"
 
 .PHONY: verify
@@ -263,6 +263,10 @@ update/gomod:
 update/shfmt: bin/shfmt
 	./bin/shfmt -w -i 2 -d ./hack/
 
+.PHONY: update/generate-license-header
+update/generate-license-header:
+	./hack/generate-license-header.sh
+
 ## Verifiers
 # Linters and similar
 

hack/generate-license-header.sh

@@ -0,0 +1,20 @@
+#!/bin/bash
+
+set -euo pipefail
+
+echo "Adding license header..."
+
+current_year=$(date +%Y)
+find . -type d \( -name "deploy" -o -name "charts" \) -prune -o -type f \( -name "*.go" -o -name "*.sh" -o -name "*.yaml" -o -name "*.yml" \) -print | while read -r file; do
+  case "$file" in
+  *.go)
+    comment_prefix="//"
+    ;;
+  *.sh | *.yaml | *.yml)
+    comment_prefix="#"
+    ;;
+  esac
+  if ! grep -q "The Kubernetes Authors." "$file"; then
+    echo -e "${comment_prefix} Copyright ${current_year} The Kubernetes Authors.\n${comment_prefix}\n${comment_prefix} Licensed under the Apache License, Version 2.0 (the 'License');\n${comment_prefix} you may not use this file except in compliance with the License.\n${comment_prefix} You may obtain a copy of the License at\n${comment_prefix}\n${comment_prefix}    http://www.apache.org/licenses/LICENSE-2.0\n${comment_prefix}\n${comment_prefix} Unless required by applicable law or agreed to in writing, software\n${comment_prefix} distributed under the License is distributed on an 'AS IS' BASIS,\n${comment_prefix} WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n${comment_prefix} See the License for the specific language governing permissions and\n${comment_prefix} limitations under the License.\n" | cat - "$file" >temp && mv temp "$file"
+  fi
+done