entrypoint.sh

#!/bin/sh
set -e

# Setup these env variables.
# - LABELS
# - PR_NUMBER
# - PR_TITLE
setup_from_push_event() {
  pull_request="$(list_pulls | jq ".[] | select(.merge_commit_sha==\"${GITHUB_SHA}\")")"
  LABELS=$(echo "${pull_request}" | jq '.labels | .[].name')
  PR_NUMBER=$(echo "${pull_request}" | jq -r .number)
  PR_TITLE=$(echo "${pull_request}" | jq -r .title)
}

list_pulls() {
  pulls_endpoint="https://api.github.com/repos/${GITHUB_REPOSITORY}/pulls?state=closed&sort=updated&direction=desc"
  if [ -n "${INPUT_GITHUB_TOKEN}" ]; then
    curl -s -H "Authorization: token ${INPUT_GITHUB_TOKEN}" "${pulls_endpoint}"
  else
    echo "INPUT_GITHUB_TOKEN is not available. Subscequent GitHub API call may fail due to API limit." >&2
    curl -s "${pulls_endpoint}"
  fi
}

setup_git() {
  git config user.name "${GITHUB_ACTOR}"
  git config user.email "${GITHUB_ACTOR}@users.noreply.github.com"
}

setup_from_push_event

BUMP_LEVEL="${INPUT_DEFAULT_BUMP_LEVEL}"
if echo "${LABELS}" | grep "bump:major" ; then
  BUMP_LEVEL="major"
elif echo "${LABELS}" | grep "bump:minor" ; then
  BUMP_LEVEL="minor"
elif echo "${LABELS}" | grep "bump:patch" ; then
  BUMP_LEVEL="patch"
fi
echo "::set-output name=level::#{BUMP_LEVEL}"

if [ -z "${BUMP_LEVEL}" ]; then
  echo "PR with labels for bump not found. Do nothing."
  echo "::set-output name=skipped::true"
  exit
else
  echo "::set-output name=skipped::false"
fi

echo "Bump ${BUMP_LEVEL} version"
if [ "${INPUT_DRY_RUN}" = "true" ]; then
  exit
fi

setup_git

CURRENT_VERSION=`jq -r ".version" package.json`
NEXT_VERSION=$(bump-version $CURRENT_VERSION $BUMP_LEVEL)

# Update package.json
jq '.version = "'"$NEXT_VERSION"'"' package.json > package.json.new
mv package.json.new package.json

# git commit, tag and push
git commit -am "Next ${BUMP_LEVEL} version: ${NEXT_VERSION}"
git tag "v${NEXT_VERSION}"
git push
git push --tags