Add Backport PR Job

github/backportPR.sh

@@ -0,0 +1,76 @@
+#!/bin/bash -eu 
+set -o pipefail 
+PR_JSON=""
+getJsonItem() {
+    echo $PR_JSON | jq -r ".$1"
+}
+
+# Sanitize PR URL
+PR_URL=$(echo ${PR_URL:-} | grep -oP 'https://github.com/[a-zA-Z0-9-_]+/[a-zA-Z0-9-_]+/pull/[0-9]+')
+if [ -z "${PR_URL:-}"]; then 
+  echo "Error: Please provide a valid PR URL!"
+  exit 1
+fi
+
+if [ -z "${TARGET_BASE_BRANCH:-}" ]; then 
+  echo "Error: Please provide a valid target base branch!"
+  exit 1
+fi
+
+echo "Analyzing the supplied PR..."
+PR_API_URI=$(echo ${PR_URL} | sed  -e 's|https://github.com|/repos|g' -e 's|/pull/|/pulls/|g' )
+PR_CLONE_URL=$(echo ${PR_URL} | sed  -e 's|https://github.com/|[email protected]:|g' -Ee 's|/pull/.*|.git|g' )
+echo $PR_API_URI $PR_CLONE_URL
+PR_JSON=$(gh api ${PR_API_URI})
+echo "Checking PR merge status..."
+PR_MERGED=$(getJsonItem merged)
+
+if ! ${PR_MERGED:-false}; then 
+  echo "Error: You should pick a merged PR!"
+  exit 1
+fi
+echo "OK PR is merged."
+echo "Checking PR merge commit"
+PR_MERGE_COMMIT=$(getJsonItem merge_commit_sha)
+echo "OK PR merge commit is ${PR_MERGE_COMMIT}"
+PR_TITLE=$(getJsonItem title)
+PR_BODY=$(getJsonItem body)
+PR_OWNER=$(getJsonItem user.login)
+PR_REPO=$(getJsonItem head.repo.name)
+git clone $PR_CLONE_URL &>/dev/null
+pushd ${PR_REPO}
+git checkout ${TARGET_BASE_BRANCH} &>/dev/null
+BRANCH_NAME=backport_$(date +%s)
+git checkout -b ${BRANCH_NAME}
+if ! git cherry-pick -x ${PR_MERGE_COMMIT}; then 
+    git cherry-pick --abort &>/dev/null || true
+    echo "Cherry-pick failed! Performing patch method..."
+    PR_PATCH_URL=$(getJsonItem patch_url)
+    wget $PR_PATCH_URL -O ../patch.diff &>/dev/null 
+    git apply ../patch.diff
+    commitFile=$(mktemp)
+    echo ${PR_TITLE} > $commitFile
+    echo >> $commitFile
+    echo ${PR_BODY} > $commitFile 
+    echo >> $commitFile
+    echo "(Cherry-picked from ${PR_MERGE_COMMIT})" > $commitFile 
+    rm ../patch.diff
+    git add . # not recommended
+    git commit -F $commitFile 
+    rm $commitFile 
+fi
+git push origin HEAD
+if [ ${REVIEWERS:-} = "_OWNER_" ]; then 
+    REVIEWERS=$PR_OWNER
+fi
+if [ ! -z ${GH_ACTOR_TOKEN:-} ]; then
+  export GH_TOKEN=${GH_ACTOR_TOKEN}
+fi
+echo "OK! Creating backport PR with base branch ${TARGET_BASE_BRANCH}, assignee ${PR_OWNER}, and reviewers ${REVIEWERS}..."
+gh pr create --repo $PR_CLONE_URL -f --reviewer "${REVIEWERS}" --assignee "${PR_OWNER}" --base "${TARGET_BASE_BRANCH}" --head ${BRANCH_NAME}
+echo "Done."
+if [ "${AUTO_MERGE:-DEFAULT}" != "DEFAULT" ]; then 
+  echo "Enabling ${AUTO_MERGE:-DEFAULT} auto merge..."
+  gh pr merge --auto --${AUTO_MERGE} --repo $PR_CLONE_URL
+  echo "Done."
+fi