[DO NOT MERGE] Verify backport label

.github/workflows/backport-check.yaml

@@ -0,0 +1,68 @@
+#
+# Copyright (C) 2019-2024 vdaas.org vald team <[email protected]>
+#
+# 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
+#
+#    https://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.
+#
+# DO NOT MERGE THIS FILE
+name: "Run backport PR"
+on:
+  push:
+    branches:
+      - main
+      - "release/v*.*"
+      - "!release/v*.*.*"
+  pull_request:
+
+env:
+  TARGET_LABEL_NAME_PREFIX: "actions/backport/"
+  BACKPORT_BRANCH_NAME_PREFIX: "backport"
+  FETCHED_GITHUB_INFO_PATH: /tmp/github_info.json
+  GITHUB_USER: ${{ secrets.DISPATCH_USER }}
+  GITHUB_TOKEN: ${{ secrets.DISPATCH_TOKEN }}
+jobs:
+  dump-contexts-to-log:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./.github/actions/dump-context
+  create:
+    runs-on: ubuntu-latest
+    needs: [dump-contexts-to-log]
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+          token: ${{ secrets.DISPATCH_TOKEN }}
+      - name: Set Git config
+        run: |
+          git config --global --add safe.directory ${GITHUB_WORKSPACE}
+      - uses: crazy-max/ghaction-import-gpg@v6
+        with:
+          gpg_private_key: ${{ secrets.GPG_PRIVATE_KEY }}
+          git_user_signingkey: true
+          git_commit_gpgsign: true
+      - name: Fetch PR info
+        run: |
+          gh pr list --limit 100 --json number,title,body,labels,headRefName,headRefOid,mergeCommit --state merged | \
+            jq --arg oid "83de9c809ffd10880caf5bcd45064bf9162f5900" '.[] | select(.mergeCommit.oid == $oid)' > ${FETCHED_GITHUB_INFO_PATH}
+          cat ${FETCHED_GITHUB_INFO_PATH}
+          echo "========"
+          gh pr list --limit 100 --json number,title,body,labels,headRefName,headRefOid,mergeCommit --state merged
+          echo "========"
+          echo ${GITHUB_SHA}
+      - name: Set context
+        id: set_context
+        run: |
+          LABEL_NAMES=`cat ${FETCHED_GITHUB_INFO_PATH} | jq -r --arg PREFIX $TARGET_LABEL_NAME_PREFIX '[.labels[]? | select(.name | startswith($PREFIX)) | .name] | join(" ")'`
+          echo "LABEL_NAMES=${LABEL_NAMES}" >> $GITHUB_OUTPUT # e.g.) actions/backport/v1.7 actions/backport/v1.8
+          echo "${LABEL_NAMES}"