Add a github action for automatically cherry-pick PRs (#13)
**Motivation**
We want to make the pulsar can cherry-pick automatically. This action will make a closed PR can cherry-pick by the command `/pulsarbot cherry-pick to branch-X.Y`.
When a PR is merged, the bot will say,
```
Hey. If you want to cherry-pick this pr to a target branch, please comments '/pulsarbot, /pulsarbot cherry-pick to branch-X.Y'.
```
Then you can comment /pulsarbot cherry-pick to branch-X.Y, the bot will open a new PR for cherry-picking the closed PR.
If we open a new PR to do the cherry-pick, we can also use the CI to check the branch.
diff --git a/.gitignore b/.gitignore
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--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+.idea
diff --git a/cherry-pick/Dockerfile b/cherry-pick/Dockerfile
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index 0000000..f087f2c
--- /dev/null
+++ b/cherry-pick/Dockerfile
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+FROM alpine:latest
+
+LABEL version="1.0.0"
+LABEL repository="http://github.com/apache/pulsar-test-infra"
+LABEL homepage="http://github.com/apache/pulsar-test-infra/pulsarbot"
+LABEL maintainer="Apache Pulsar Team"
+LABEL "com.github.actions.name"="pulsarbot"
+LABEL "com.github.actions.description"="Pulsar Bot"
+LABEL "com.github.actions.icon"="git-commit"
+LABEL "com.github.actions.color"="gray-dark"
+
+RUN apk add --update git jq bash curl coreutils && rm -rf /var/cache/apk/*
+
+RUN curl -LO -s https://github.com/cli/cli/releases/download/v1.2.0/gh_1.2.0_linux_386.tar.gz && \
+ tar -xf gh_1.2.0_linux_386.tar.gz
+
+ENV PATH=${PATH}:/gh_1.2.0_linux_386/bin
+
+COPY entrypoint.sh /entrypoint.sh
+
+ENTRYPOINT ["/entrypoint.sh"]
diff --git a/cherry-pick/README.md b/cherry-pick/README.md
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+++ b/cherry-pick/README.md
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+# Cherry-pick for Github Action
+
+This action used for cherry-picking the PRs automatically.
+
+When you close a PR then the bot will prompt you:
+
+```bash
+Hey. If you want to cherry-pick this pr to a target branch, please comments '/pulsarbot cherry-pick to branch-x.y'.
+```
+
+Then you can comment `'/pulsarbot cherry-pick to branch-x.y'`, and the bot will create a new PR to merge it into the target branch.
diff --git a/cherry-pick/action.yml b/cherry-pick/action.yml
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+++ b/cherry-pick/action.yml
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+name: 'cherry-pick'
+description: 'Automatically cherry-pick PRs for apache pulsar'
+inputs:
+ type:
+ description: 'Give a prompt or execute the cherry-pick, available options [cherry-pick] or [prompt-comment]'
+ required: true
+ default: 'cherry-pick'
+ github_user:
+ description: 'The github user who to do the commit the changes'
+ required: true
+ github_email:
+ description: 'The github user email who to do the commit changes'
+ required: true
+ github_repos:
+ description: 'The '
+ required: true
+ default: 'apache/pulsar'
+runs:
+ using: 'docker'
+ image: 'Dockerfile'
+ args:
+ - ${{ inputs.type }}
+ - ${{ inputs.github_user }}
+ - ${{ inputs.github_email }}
+ - ${{ inputs.github_repos }}
diff --git a/cherry-pick/entrypoint.sh b/cherry-pick/entrypoint.sh
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index 0000000..72efc42
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+++ b/cherry-pick/entrypoint.sh
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+#!/bin/bash
+
+set -x
+
+cat ${GITHUB_EVENT_PATH}
+
+GITHUB_TOKEN=${GITHUB_TOKEN:-""}
+
+configure_args() {
+ readonly GITHUB_USER=${1}
+ readonly GITHUB_EMAIL=${2}
+ readonly GITHUB_REPOS=${3}
+}
+
+# Get the PR merged sha and the title
+cherrypick_args() {
+ readonly COMMENT_BODY=$(jq -r '.comment.body' ${GITHUB_EVENT_PATH})
+ readonly PR_NUMBER=$(jq -r '.issue.number' "$GITHUB_EVENT_PATH")
+
+ readonly BOT_BRANCH_NAME="pulsarbot/cherry-pick-${PR_NUMBER}"
+ readonly BOT_PR_TITLE_PREFIX="[bot-cherry-pick]"
+ if [[ "" == "${GITHUB_TOKEN}" ]]; then
+ readonly PR_INFO=$(curl -s --request GET \
+ --url https://api.github.com/repos/${GITHUB_REPOS}/pulls/${PR_NUMBER} \
+ --header 'Accept: application/vnd.github.sailor-v-preview+json')
+ else
+ readonly PR_INFO=$(curl -s --request GET \
+ --url https://api.github.com/repos/${GITHUB_REPOS}/pulls/${PR_NUMBER} \
+ --header "Authorization: token ${GITHUB_TOKEN}" \
+ --header 'Accept: application/vnd.github.sailor-v-preview+json')
+ fi
+
+ readonly PR_MERGE_COMMIT_SHA=`echo ${PR_INFO} | jq -r .merge_commit_sha`
+ readonly PR_TITLE=`echo ${PR_INFO} | jq -r .title`
+}
+
+# setup github for commit the changes
+git_setup() {
+ git config user.name "${GITHUB_USER}"
+ git config user.email "${GITHUB_EMAIL}"
+}
+
+check_pr_is_merged() {
+ MERGED=`echo ${PR_INFO} | jq -r .merged`
+ if [[ "false" == ${MERGED} ]]; then
+ echo "PR is not merged"
+ exit 0
+ fi
+}
+
+cherrypick() {
+ check_pr_is_merged
+ TARGET_BRANCH=`echo ${COMMENT_BODY} | grep -o "branch-[0-9].[0-9]"`
+ if [[ "" == ${TARGET_BRANCH} ]]; then
+ echo "Wrong target branch"
+ exit 1
+ fi
+ git fetch --all
+ git checkout ${TARGET_BRANCH}
+ git checkout -b ${BOT_BRANCH_NAME}
+ git status
+ git cherry-pick "${PR_MERGE_COMMIT_SHA}" -X Recursive
+ status=$?
+ if [[ ${status} != 0 ]]; then
+ git add .
+ git commit --allow-empty -m "${BOT_PR_TITLE_PREFIX}${PR_TITLE}"
+ fi
+ git push origin ${BOT_BRANCH_NAME}
+ gh pr create --title "${BOT_PR_TITLE_PREFIX}${PR_TITLE}" --fill --base ${TARGET_BRANCH}
+}
+
+pr_close_prompt_args() {
+ readonly PR_NUMBER=$(jq -r '.number' "${GITHUB_EVENT_PATH}")
+ readonly PR_INFO=$(curl -s --request GET \
+ --url https://api.github.com/repos/${GITHUB_REPOS}/pulls/${PR_NUMBER} \
+ --header "Authorization: token ${GITHUB_TOKEN}" \
+ --header 'Accept: application/vnd.github.sailor-v-preview+json')
+}
+
+pr_close_prompt() {
+ check_pr_is_merged
+ COMMENTS_URL=`echo ${PR_INFO} | jq -r ._links.comments.href`
+ REVIEWS=`echo ${PR_INFO} | jq '.requested_reviewers[] | .login'`
+ users=""
+ for review in ${REVIEWS}; do
+ users="${users}, @${review}"
+ done
+ if [[ "" == ${users} ]]; then
+ PROMPT_SENTENCE="Hey. If you want to cherry-pick this pr to a target branch, please comments '/pulsarbot cherry-pick to branch-x.y'."
+ else
+ PROMPT_SENTENCE="Hey, ${users}. If you want to cherry-pick this pr to a target branch, please comments '/pulsarbot cherry-pick to branch-x.y'."
+ fi
+
+ if [[ "" == "${GITHUB_TOKEN}" ]]; then
+ curl --request POST \
+ --url ${COMMENTS_URL} \
+ --data "{\"body\": \"${PROMPT_SENTENCE}\"}"
+ else
+ curl --request POST \
+ --url ${COMMENTS_URL} \
+ --header "Authorization: token ${GITHUB_TOKEN}" \
+ --data "{\"body\": \"${PROMPT_SENTENCE}\"}"
+ fi
+}
+
+echo ${1}
+case ${1} in
+ cherry-pick)
+ shift
+ configure_args ${@}
+ git_setup
+ cherrypick_args
+ cherrypick
+ ;;
+ prompt-comment)
+ shift
+ configure_args ${@}
+ pr_close_prompt_args
+ pr_close_prompt
+ ;;
+esac
+
