hack: add license headers tool

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>

docker-bake.hcl

@@ -7,7 +7,7 @@ group "pre-checkin" {
 }
 
 group "validate" {
-  targets = ["lint", "vendor-validate"]
+  targets = ["lint", "vendor-validate", "license-validate"]
 }
 
 target "build" {
@@ -69,3 +69,15 @@ target "publish" {
   output = ["type=cacheonly"]
   secret = ["id=NODE_AUTH_TOKEN,env=NODE_AUTH_TOKEN"]
 }
+
+target "license-validate" {
+  dockerfile = "./hack/dockerfiles/license.Dockerfile"
+  target = "validate"
+  output = ["type=cacheonly"]
+}
+
+target "license-update" {
+  dockerfile = "./hack/dockerfiles/license.Dockerfile"
+  target = "update"
+  output = ["."]
+}

hack/dockerfiles/license.Dockerfile

@@ -0,0 +1,33 @@
+# syntax=docker/dockerfile:1
+
+ARG LICENSE_HOLDER="actions-toolkit authors"
+ARG LICENSE_TYPE="apache"
+ARG LICENSE_FILES=".*\(Dockerfile\|Makefile\|\.js\|\.ts\|\.hcl\|\.sh\)"
+ARG ADDLICENSE_VERSION="v1.0.0"
+
+FROM ghcr.io/google/addlicense:${ADDLICENSE_VERSION} AS addlicense
+
+FROM alpine:3.17 AS base
+WORKDIR /src
+RUN apk add --no-cache cpio findutils git
+
+FROM base AS set
+ARG LICENSE_HOLDER
+ARG LICENSE_TYPE
+ARG LICENSE_FILES
+RUN --mount=type=bind,target=.,rw \
+    --mount=from=addlicense,source=/app/addlicense,target=/usr/bin/addlicense \
+    find . -regex "${LICENSE_FILES}" -not -path "./.yarn/*" -not -path "./node_modules/*" | xargs addlicense -c "$LICENSE_HOLDER" -l "$LICENSE_TYPE" && \
+    mkdir /out && \
+    find . -regex "${LICENSE_FILES}" -not -path "./.yarn/*" -not -path "./node_modules/*" | cpio -pdm /out
+
+FROM scratch AS update
+COPY --from=set /out /
+
+FROM base AS validate
+ARG LICENSE_HOLDER
+ARG LICENSE_TYPE
+ARG LICENSE_FILES
+RUN --mount=type=bind,target=. \
+    --mount=from=addlicense,source=/app/addlicense,target=/usr/bin/addlicense \
+    find . -regex "${LICENSE_FILES}" -not -path "./.yarn/*" -not -path "./node_modules/*" | xargs addlicense -check -c "$LICENSE_HOLDER" -l "$LICENSE_TYPE"