add cherry-pick-pull from upstream along with docs for backporting (#643

) * add cherry-pick-pull from upstream along with docs for backporting * add note to readme * Update docs/developer/cherry-picks.md Co-authored-by: Taylor Neyland <57606775+taneyland@users.noreply.github.com> Co-authored-by: Taylor Neyland <57606775+taneyland@users.noreply.github.com>
aws · Nov 18, 2021 · 2b16d99 · 2b16d99
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diff --git a/README.md b/README.md
@@ -33,6 +33,8 @@ Refer to our [end to end guide](https://github.com/aws/eks-anywhere/tree/main/te
 The dependencies which make up EKS Anywhere are defined and built via the [build-tooling](https://github.com/aws/eks-anywhere-build-tooling) repo.
 To update dependencies please review the Readme for the specific dependency before opening a PR.
 
+See [Cherry picking](./docs/developer/cherry-picks.md) for backporting to release branches
+
 ## Security
 
 If you discover a potential security issue in this project, or think you may

diff --git a/docs/developer/cherry-picks.md b/docs/developer/cherry-picks.md
@@ -0,0 +1,29 @@
+# Release Branches
+
+eks-anywhere maintains multiple release branches to represent the currently supported versions.  
+
+In general, bug fixes should be backported to currently supported release branches, new features should not.
+
+## Currently supported release branches
+
+- [release-0.6](https://github.com/aws/eks-anywhere/tree/release-0.6)
+
+# "Automated" Cherry Picks
+
+The [cherry_pick_pull.sh](../../hack/cherry_pick_pull.sh) is provided 
+to assist in backporting.  The script is the same used by upstream [kubernetes/kubernetes](https://github.com/kubernetes/kubernetes/blob/master/hack/cherry_pick_pull.sh)
+
+## To create a Cherry Pick
+
+- Open + Merge PR in eks-anywhere repo
+- Run `GITHUB_USER=<github_user> ./build/lib/cherry_pick_pull.sh upstream/<release-branch> <pr number>`
+	- The script assumes your remotes are setup such that `upstream` points the `aws/eks-anywhere` and `origin`
+	points to your fork at `<github_user>/eks-anywhere`
+	- If your remotes are not setup this way you can set `UPSTREAM_REMOTE=<upstream remote name>` `FORK_REMOTE=<fork remote name>`
+	when calling the script to override the defaults
+	- There a couple of pre-reqs, having a `GITHUB_TOKEN` set and the `gh` cli installed.  The script will let you know if you are missing any of these
+- If there is a merge conflict, the script will wait and give you a chance to fix conflicts in another terminal before continuing
+- The script will push a new branch and open a PR automatically
+- Run the above script for each currently supported release branch
+
+Refer to the upstream [doc](https://github.com/kubernetes/community/blob/master/contributors/devel/sig-release/cherry-picks.md) for more information.
diff --git a/hack/cherry_pick_pull.sh b/hack/cherry_pick_pull.sh
@@ -0,0 +1,251 @@
+#!/usr/bin/env bash
+
+# Copyright 2015 The Kubernetes Authors.
+# - https://github.com/kubernetes/kubernetes/blob/master/hack/cherry_pick_pull.sh
+# Modifications Copyright Amazon.com Inc. or its affiliates. All Rights Reserved. Licensed under the Apache2 License
+
+# Modifications:
+# - changed instructions link to doc in this repo instead of upstream
+# - harcoded MAIN_REPO_ORG and MAIN_REPO_NAME to avoid difference with awk on mac vs linux
+
+# Usage Instructions: https://github.com/aws/eks-anywhere-build-tooling/tree/main/docs/development/cherry-picks.md
+
+# Checkout a PR from GitHub. (Yes, this is sitting in a Git tree. How
+# meta.) Assumes you care about pulls from remote "upstream" and
+# checks them out to a branch named:
+#  automated-cherry-pick-of-<pr>-<target branch>-<timestamp>
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+REPO_ROOT="$(git rev-parse --show-toplevel)"
+declare -r REPO_ROOT
+cd "${REPO_ROOT}"
+
+STARTINGBRANCH=$(git symbolic-ref --short HEAD)
+declare -r STARTINGBRANCH
+declare -r REBASEMAGIC="${REPO_ROOT}/.git/rebase-apply"
+DRY_RUN=${DRY_RUN:-""}
+REGENERATE_DOCS=${REGENERATE_DOCS:-""}
+UPSTREAM_REMOTE=${UPSTREAM_REMOTE:-upstream}
+FORK_REMOTE=${FORK_REMOTE:-origin}
+MAIN_REPO_ORG=aws # ${MAIN_REPO_ORG:-$(git remote get-url "$UPSTREAM_REMOTE" | awk '{gsub(/http[s]:\/\/|git@/,"")}1' | awk -F'[@:./]' 'NR==1{print $3}')}
+MAIN_REPO_NAME=eks-anywhere # ${MAIN_REPO_NAME:-$(git remote get-url "$UPSTREAM_REMOTE" | awk '{gsub(/http[s]:\/\/|git@/,"")}1' | awk -F'[@:./]' 'NR==1{print $4}')}
+
+if [[ -z ${GITHUB_USER:-} ]]; then
+  echo "Please export GITHUB_USER=<your-user> (or GH organization, if that's where your fork lives)"
+  exit 1
+fi
+
+if ! command -v gh > /dev/null; then
+  echo "Can't find 'gh' tool in PATH, please install from https://github.com/cli/cli"
+  exit 1
+fi
+
+if [[ "$#" -lt 2 ]]; then
+  echo "${0} <remote branch> <pr-number>...: cherry pick one or more <pr> onto <remote branch> and leave instructions for proposing pull request"
+  echo
+  echo "  Checks out <remote branch> and handles the cherry-pick of <pr> (possibly multiple) for you."
+  echo "  Examples:"
+  echo "    $0 upstream/release-3.14 12345        # Cherry-picks PR 12345 onto upstream/release-3.14 and proposes that as a PR."
+  echo "    $0 upstream/release-3.14 12345 56789  # Cherry-picks PR 12345, then 56789 and proposes the combination as a single PR."
+  echo
+  echo "  Set the DRY_RUN environment var to skip git push and creating PR."
+  echo "  This is useful for creating patches to a release branch without making a PR."
+  echo "  When DRY_RUN is set the script will leave you in a branch containing the commits you cherry-picked."
+  echo
+  echo "  Set the REGENERATE_DOCS environment var to regenerate documentation for the target branch after picking the specified commits."
+  echo "  This is useful when picking commits containing changes to API documentation."
+  echo
+  echo "  Set UPSTREAM_REMOTE (default: upstream) and FORK_REMOTE (default: origin)"
+  echo "  to override the default remote names to what you have locally."
+  echo
+  echo "  For merge process info, see https://github.com/aws/eks-anywhere-build-tooling/tree/main/docs/development/cherry-picks.md"
+  exit 2
+fi
+
+# Checks if you are logged in. Will error/bail if you are not.
+gh auth status
+
+if git_status=$(git status --porcelain --untracked=no 2>/dev/null) && [[ -n "${git_status}" ]]; then
+  echo "!!! Dirty tree. Clean up and try again."
+  exit 1
+fi
+
+if [[ -e "${REBASEMAGIC}" ]]; then
+  echo "!!! 'git rebase' or 'git am' in progress. Clean up and try again."
+  exit 1
+fi
+
+declare -r BRANCH="$1"
+shift 1
+declare -r PULLS=( "$@" )
+
+function join { local IFS="$1"; shift; echo "$*"; }
+PULLDASH=$(join - "${PULLS[@]/#/#}") # Generates something like "#12345-#56789"
+declare -r PULLDASH
+PULLSUBJ=$(join " " "${PULLS[@]/#/#}") # Generates something like "#12345 #56789"
+declare -r PULLSUBJ
+
+echo "+++ Updating remotes..."
+git remote update "${UPSTREAM_REMOTE}" "${FORK_REMOTE}"
+
+if ! git log -n1 --format=%H "${BRANCH}" >/dev/null 2>&1; then
+  echo "!!! '${BRANCH}' not found. The second argument should be something like ${UPSTREAM_REMOTE}/release-0.21."
+  echo "    (In particular, it needs to be a valid, existing remote branch that I can 'git checkout'.)"
+  exit 1
+fi
+
+NEWBRANCHREQ="automated-cherry-pick-of-${PULLDASH}" # "Required" portion for tools.
+declare -r NEWBRANCHREQ
+NEWBRANCH="$(echo "${NEWBRANCHREQ}-${BRANCH}" | sed 's/\//-/g')"
+declare -r NEWBRANCH
+NEWBRANCHUNIQ="${NEWBRANCH}-$(date +%s)"
+declare -r NEWBRANCHUNIQ
+echo "+++ Creating local branch ${NEWBRANCHUNIQ}"
+
+cleanbranch=""
+gitamcleanup=false
+function return_to_kansas {
+  if [[ "${gitamcleanup}" == "true" ]]; then
+    echo
+    echo "+++ Aborting in-progress git am."
+    git am --abort >/dev/null 2>&1 || true
+  fi
+
+  # return to the starting branch and delete the PR text file
+  if [[ -z "${DRY_RUN}" ]]; then
+    echo
+    echo "+++ Returning you to the ${STARTINGBRANCH} branch and cleaning up."
+    git checkout -f "${STARTINGBRANCH}" >/dev/null 2>&1 || true
+    if [[ -n "${cleanbranch}" ]]; then
+      git branch -D "${cleanbranch}" >/dev/null 2>&1 || true
+    fi
+  fi
+}
+trap return_to_kansas EXIT
+
+SUBJECTS=()
+function make-a-pr() {
+  local rel
+  rel="$(basename "${BRANCH}")"
+  echo
+  echo "+++ Creating a pull request on GitHub at ${GITHUB_USER}:${NEWBRANCH}"
+
+  local numandtitle
+  numandtitle=$(printf '%s\n' "${SUBJECTS[@]}")
+  prtext=$(cat <<EOF
+Cherry pick of ${PULLSUBJ} on ${rel}.
+
+${numandtitle}
+
+For details on the cherry pick process, see the [cherry pick requests](https://github.com/aws/eks-anywhere-build-tooling/tree/main/docs/development/cherry-picks.md) page.
+
+\`\`\`release-note
+
+\`\`\`
+EOF
+)
+
+  gh pr create --title="Automated cherry pick of ${numandtitle}" --body="${prtext}" --head "${GITHUB_USER}:${NEWBRANCH}" --base "${rel}" --repo="${MAIN_REPO_ORG}/${MAIN_REPO_NAME}"
+}
+
+git checkout -b "${NEWBRANCHUNIQ}" "${BRANCH}"
+cleanbranch="${NEWBRANCHUNIQ}"
+
+gitamcleanup=true
+for pull in "${PULLS[@]}"; do
+  echo "+++ Downloading patch to /tmp/${pull}.patch (in case you need to do this again)"
+
+  curl -o "/tmp/${pull}.patch" -sSL "https://github.com/${MAIN_REPO_ORG}/${MAIN_REPO_NAME}/pull/${pull}.patch"
+  echo
+  echo "+++ About to attempt cherry pick of PR. To reattempt:"
+  echo "  $ git am -3 /tmp/${pull}.patch"
+  echo
+  git am -3 "/tmp/${pull}.patch" || {
+    conflicts=false
+    while unmerged=$(git status --porcelain | grep ^U) && [[ -n ${unmerged} ]] \
+      || [[ -e "${REBASEMAGIC}" ]]; do
+      conflicts=true # <-- We should have detected conflicts once
+      echo
+      echo "+++ Conflicts detected:"
+      echo
+      (git status --porcelain | grep ^U) || echo "!!! None. Did you git am --continue?"
+      echo
+      echo "+++ Please resolve the conflicts in another window (and remember to 'git add / git am --continue')"
+      read -p "+++ Proceed (anything but 'y' aborts the cherry-pick)? [y/n] " -r
+      echo
+      if ! [[ "${REPLY}" =~ ^[yY]$ ]]; then
+        echo "Aborting." >&2
+        exit 1
+      fi
+    done
+
+    if [[ "${conflicts}" != "true" ]]; then
+      echo "!!! git am failed, likely because of an in-progress 'git am' or 'git rebase'"
+      exit 1
+    fi
+  }
+
+  # set the subject
+  subject=$(grep -m 1 "^Subject" "/tmp/${pull}.patch" | sed -e 's/Subject: \[PATCH//g' | sed 's/.*] //')
+  SUBJECTS+=("#${pull}: ${subject}")
+
+  # remove the patch file from /tmp
+  rm -f "/tmp/${pull}.patch"
+done
+gitamcleanup=false
+
+# Re-generate docs (if needed)
+if [[ -n "${REGENERATE_DOCS}" ]]; then
+  echo
+  echo "Regenerating docs..."
+  if ! hack/generate-docs.sh; then
+    echo
+    echo "hack/generate-docs.sh FAILED to complete."
+    exit 1
+  fi
+fi
+
+if [[ -n "${DRY_RUN}" ]]; then
+  echo "!!! Skipping git push and PR creation because you set DRY_RUN."
+  echo "To return to the branch you were in when you invoked this script:"
+  echo
+  echo "  git checkout ${STARTINGBRANCH}"
+  echo
+  echo "To delete this branch:"
+  echo
+  echo "  git branch -D ${NEWBRANCHUNIQ}"
+  exit 0
+fi
+
+if git remote -v | grep ^"${FORK_REMOTE}" | grep "${MAIN_REPO_ORG}/${MAIN_REPO_NAME}.git"; then
+  echo "!!! You have ${FORK_REMOTE} configured as your ${MAIN_REPO_ORG}/${MAIN_REPO_NAME}.git"
+  echo "This isn't normal. Leaving you with push instructions:"
+  echo
+  echo "+++ First manually push the branch this script created:"
+  echo
+  echo "  git push REMOTE ${NEWBRANCHUNIQ}:${NEWBRANCH}"
+  echo
+  echo "where REMOTE is your personal fork (maybe ${UPSTREAM_REMOTE}? Consider swapping those.)."
+  echo "OR consider setting UPSTREAM_REMOTE and FORK_REMOTE to different values."
+  echo
+  make-a-pr
+  cleanbranch=""
+  exit 0
+fi
+
+echo
+echo "+++ I'm about to do the following to push to GitHub (and I'm assuming ${FORK_REMOTE} is your personal fork):"
+echo
+echo "  git push ${FORK_REMOTE} ${NEWBRANCHUNIQ}:${NEWBRANCH}"
+echo
+read -p "+++ Proceed (anything but 'y' aborts the cherry-pick)? [y/n] " -r
+if ! [[ "${REPLY}" =~ ^[yY]$ ]]; then
+  echo "Aborting." >&2
+  exit 1
+fi
+
+git push "${FORK_REMOTE}" -f "${NEWBRANCHUNIQ}:${NEWBRANCH}"
+make-a-pr