Add community contribution PR mirroring

tooling/mirror-community-pull-request.sh

@@ -0,0 +1,200 @@
+#!/bin/bash
+set -e
+
+#
+# Handling community pull requests.
+#
+# The main way to handle community contributions is to contribute directly on the contributor's pull request.
+# If not enabled, please ask the contributor to enable the option "Allow edits by maintainers".
+# This allows maintainers to push commits to the contributor's branch.
+# Then, use this script to mirror the PR to a new branch in the main repository.
+# This allows running CI with the maintainer's permissions.
+#
+# Few hints:
+# - Avoid merge commits with master and rebase the contributor's branch instead.
+# - Avoid pushing changes to the mirror branch as it will be overwritten when rerunning the script.
+#
+# Usage: mirror-community-pull-request.sh <pr-number> [<target-branch>]
+
+REPO="DataDog/dd-trace-java"
+PR_NUMBER=$1
+TARGET_BRANCH=${2:-master}
+MIRROR_BRANCH="community-pr-$PR_NUMBER"
+
+#
+# Check arguments.
+#
+# Check if no arguments are provided
+if [ $# -eq 0 ]; then
+    echo "Usage: $0 <pr-number> [<target-branch>]"
+    echo "<pr-number>: PR number to mirror"
+    echo "<target-branch>: Target branch for the mirror (default: master)"
+    echo ""
+    echo "This script mirrors a community PR to allow running CI with your own account."
+    echo "It creates a new branch 'community-pr-<number>' and pushes the PR changes."
+    exit 1
+fi
+# Check PR number is provided
+if [ -z "$PR_NUMBER" ]; then
+    echo "❌ PR number is not provided"
+    exit 1
+fi
+# Validate PR number is numeric
+if ! [[ "$PR_NUMBER" =~ ^[0-9]+$ ]]; then
+    echo "❌ PR number must be numeric"
+    exit 1
+fi
+
+#
+# Check requirements.
+#
+echo "- Checking requirements"
+# Check gh is installed
+gh --version 1>/dev/null 2>&1 || { echo "❌ gh is not installed. Please install GitHub CLI."; exit 1; }
+# Check jq is installed
+jq --version 1>/dev/null 2>&1 || { echo "❌ jq is not installed. Please install jq."; exit 1; }
+# Check there are no local changes
+git diff --exit-code || { echo "❌ There are local changes. Please commit or stash them."; exit 1; }
+
+#
+# Fetch PR information.
+#
+echo "- Fetching PR #$PR_NUMBER details"
+# Check if PR exists and get details
+PR_DATA=$(gh pr view "$PR_NUMBER" --json headRepository,headRepositoryOwner,headRefName,title,number,state,author 2>/dev/null || echo "")
+if [ -z "$PR_DATA" ]; then
+    echo "❌ PR #$PR_NUMBER not found"
+    exit 1
+fi
+# Parse PR details
+FORK_REPO=$(echo "$PR_DATA" | jq -r '(.headRepository.nameWithOwner // (.headRepositoryOwner.login + "/" + .headRepository.name)) // empty')
+FORK_BRANCH=$(echo "$PR_DATA" | jq -r '.headRefName // empty')
+PR_TITLE=$(echo "$PR_DATA" | jq -r '.title // empty')
+PR_AUTHOR=$(echo "$PR_DATA" | jq -r '.author.login // empty')
+PR_LABELS=$(gh pr view "$PR_NUMBER" --json labels --jq '[.labels[].name] | join(",")')
+if [ -z "$FORK_REPO" ] || [ -z "$FORK_BRANCH" ]; then
+    echo "❌ Could not determine fork repository or branch for PR #$PR_NUMBER"
+    exit 1
+fi
+
+#
+# Create mirror branch.
+#
+echo "- Mirroring PR #$PR_NUMBER from $FORK_REPO:$FORK_BRANCH to $REPO:$MIRROR_BRANCH"
+# Check if mirror branch already exists
+echo "- Checking if mirror branch $MIRROR_BRANCH already exists locally"
+if git show-ref --verify --quiet "refs/heads/$MIRROR_BRANCH" 2>/dev/null; then
+    echo -n "Branch $MIRROR_BRANCH already exists locally. Delete it to recreate? (y/n)"
+    read -r ANSWER
+    if [ "$ANSWER" = "y" ]; then
+        git branch -D "$MIRROR_BRANCH"
+    else
+        echo "Aborting."
+        exit 1
+    fi
+fi
+# Check if mirror branch exists on remote
+echo "- Checking if mirror branch $MIRROR_BRANCH already exists on remote"
+if git show-ref --verify --quiet "refs/remotes/origin/$MIRROR_BRANCH" 2>/dev/null; then
+    echo -n "Branch $MIRROR_BRANCH already exists on remote. Force push over it? (y/n)"
+    read -r ANSWER
+    if [ "$ANSWER" != "y" ]; then
+        echo "Aborting."
+        exit 1
+    fi
+fi
+# Fetch the PR branch from the fork directly (no remote needed)
+git fetch --quiet "https://github.com/$FORK_REPO.git" "$FORK_BRANCH"
+# Get list of commits from the PR to re-sign them
+echo "- Getting list of commits from PR"
+PR_COMMITS=$(gh pr view "$PR_NUMBER" --json commits --jq '.commits[].oid')
+if [ -z "$PR_COMMITS" ]; then
+    echo "❌ No commits found in PR #$PR_NUMBER"
+    exit 1
+fi
+# Get current git branch for cleanup
+CURRENT_BRANCH=$(git rev-parse --abbrev-ref HEAD)
+# Create the mirror branch from target branch (we'll cherry-pick commits)
+echo "- Creating mirror branch $MIRROR_BRANCH from $TARGET_BRANCH"
+git fetch --quiet origin "$TARGET_BRANCH"
+git checkout -b "$MIRROR_BRANCH" "origin/$TARGET_BRANCH"
+
+#
+# Mirror commits.
+#
+# Cherry-pick each commit with signature to ensure all commits are signed
+echo "- Cherry-picking and signing commits from PR"
+for COMMIT in $PR_COMMITS; do
+    echo "  - Cherry-picking $COMMIT"
+    # Check if this is a merge commit
+    CHERRY_PICK_ARGS="-S"
+    PARENT_COUNT=$(git rev-list --parents -n 1 "$COMMIT" 2>/dev/null | wc -w)
+    if [ "$PARENT_COUNT" -gt 2 ]; then
+        CHERRY_PICK_ARGS="$CHERRY_PICK_ARGS -m 1"
+    fi
+    if ! git cherry-pick "$CHERRY_PICK_ARGS" "$COMMIT"; then
+        # Check if it's an empty commit
+        if ! git diff --cached --quiet || ! git diff --quiet; then
+            echo "❌ Failed to cherry-pick merge commit $COMMIT"
+            echo "You may need to resolve conflicts manually"
+            exit 1
+        else
+            echo "    (empty commit, skipping)"
+            git cherry-pick --skip
+        fi
+    fi
+done
+# Push the mirror branch to origin
+echo "- Pushing $MIRROR_BRANCH to origin"
+git push -u origin "$MIRROR_BRANCH" --no-verify --force-with-lease
+
+#
+# Create PR if it doesn't exist.
+#
+echo "- Checking if PR already exists for branch $MIRROR_BRANCH"
+EXISTING_PR=$(gh pr list --head "$MIRROR_BRANCH" --json number --jq '.[0].number // empty' 2>/dev/null)
+if [ -n "$EXISTING_PR" ]; then
+    MIRROR_PR_URL="https://github.com/$REPO/pull/$EXISTING_PR"
+else
+    echo "- Creating new PR for mirror branch $MIRROR_BRANCH"
+    # Create PR body with reference to original
+    MIRROR_PR_BODY="This PR mirrors the changes from the original community contribution to enable CI testing with maintainer privileges.
+
+**Original PR:** https://github.com/$REPO/pull/$PR_NUMBER
+**Original Author:** @$PR_AUTHOR
+**Original Branch:** $FORK_REPO:$FORK_BRANCH
+
+Closes #$PR_NUMBER
+
+---
+
+*This is an automated mirror created to run CI checks. See tooling/mirror-community-pull-request.sh for details.*"
+
+    # Create the PR
+    CREATE_ARGS=(--base "$TARGET_BRANCH" --head "$MIRROR_BRANCH" --title "🪞 $PR_NUMBER - $PR_TITLE" --body "$MIRROR_PR_BODY")
+    if [ -n "$PR_LABELS" ]; then
+        CREATE_ARGS+=(--label "$PR_LABELS")
+    fi
+    MIRROR_PR_NUMBER=$(gh pr create "${CREATE_ARGS[@]}" 2>/dev/null | grep -o '[0-9]*$')
+    if [ -n "$MIRROR_PR_NUMBER" ]; then
+        echo "- Created mirror PR: #$MIRROR_PR_NUMBER"
+        MIRROR_PR_URL="https://github.com/$REPO/pull/$MIRROR_PR_NUMBER"
+    else
+        echo "- Failed to create PR automatically"
+        MIRROR_PR_URL="https://github.com/$REPO/compare/$TARGET_BRANCH...$MIRROR_BRANCH"
+    fi
+fi
+
+echo ""
+echo "✅ Successfully mirrored PR #$PR_NUMBER"
+echo "   Original: https://github.com/$REPO/pull/$PR_NUMBER (@$PR_AUTHOR)"
+echo "   Mirror: $MIRROR_PR_URL"
+echo "   Branch: $REPO:$MIRROR_BRANCH"
+
+#
+# Clean up.
+#
+echo "- Restoring original branch"
+git checkout "$CURRENT_BRANCH"
+
+echo "Done."