entrypoint.sh

#!/usr/bin/env bash

set -e
set -o pipefail

if [[ -z "$GITHUB_TOKEN" ]]; then
  echo "Set the GITHUB_TOKEN environment variable."
  exit 1
fi

if [[ ! -z "$INPUT_SOURCE_BRANCH" ]]; then
  SOURCE_BRANCH="$INPUT_SOURCE_BRANCH"
elif [[ ! -z "$GITHUB_REF" ]]; then
  SOURCE_BRANCH=${GITHUB_REF/refs\/heads\//}  # Remove branch prefix
else
  echo "Set the INPUT_SOURCE_BRANCH environment variable or trigger from a branch."
  exit 1
fi

DESTINATION_BRANCH="${INPUT_DESTINATION_BRANCH:-"master"}"

# Github actions no longer auto set the username and GITHUB_TOKEN
# git remote set-url origin "https://$GITHUB_ACTOR:$GITHUB_TOKEN@github.com/$GITHUB_REPOSITORY"
# TODO set token globally to not change the local config. For act execution
git config --global url."https://api:$GITHUB_TOKEN@github.com/".insteadOf "https://github.com/"
git config --global url."https://ssh:$GITHUB_TOKEN@github.com/".insteadOf "ssh://git@github.com/"
git config --global url."https://git:$GITHUB_TOKEN@github.com/".insteadOf "git@github.com:"

# Pull all branches references down locally so subsequent commands can see them
git fetch origin '+refs/heads/*:refs/heads/*' --update-head-ok

# Print out all branches
git --no-pager branch -a -vv

if [ "$(git rev-parse --revs-only "$SOURCE_BRANCH")" = "$(git rev-parse --revs-only "$DESTINATION_BRANCH")" ]; then 
  echo "Source and destination branches are the same." 
  exit 0
fi

# Do not proceed if there are no file differences, this avoids PRs with just a merge commit and no content
LINES_CHANGED=$(git diff --name-only "$DESTINATION_BRANCH" "$SOURCE_BRANCH" -- | wc -l | awk '{print $1}')
if [[ "$LINES_CHANGED" = "0" ]] && [[ ! "$INPUT_PR_ALLOW_EMPTY" ==  "true" ]]; then
  echo "No file changes detected between source and destination branches." 
  exit 0
fi


# Workaround for `hub` auth error https://github.com/github/hub/issues/2149#issuecomment-513214342
export GITHUB_USER="$GITHUB_ACTOR"

# https://github.com/github/hub/issues/1067#issuecomment-728886966
mkdir -p ~/.config
printf 'github.com:\n- user: api\n  oauth_token:  $GITHUB_TOKEN' > ~/.config/hub

PR_ARG="$INPUT_PR_TITLE"
if [[ ! -z "$PR_ARG" ]]; then
  PR_ARG="-m \"$PR_ARG\""

  if [[ ! -z "$INPUT_PR_TEMPLATE" ]]; then
    sed -i 's/`/\\`/g; s/\$/\\\$/g' "$INPUT_PR_TEMPLATE"
    PR_ARG="$PR_ARG -m \"$(echo -e "$(cat "$INPUT_PR_TEMPLATE")")\""
  elif [[ ! -z "$INPUT_PR_BODY" ]]; then
    PR_ARG="$PR_ARG -m \"$INPUT_PR_BODY\""
  fi
fi

if [[ ! -z "$INPUT_PR_REVIEWER" ]]; then
  PR_ARG="$PR_ARG -r \"$INPUT_PR_REVIEWER\""
fi

if [[ ! -z "$INPUT_PR_ASSIGNEE" ]]; then
  PR_ARG="$PR_ARG -a \"$INPUT_PR_ASSIGNEE\""
fi

if [[ ! -z "$INPUT_PR_LABEL" ]]; then
  PR_ARG="$PR_ARG -l \"$INPUT_PR_LABEL\""
fi

if [[ ! -z "$INPUT_PR_MILESTONE" ]]; then
  PR_ARG="$PR_ARG -M \"$INPUT_PR_MILESTONE\""
fi

if [[ "$INPUT_PR_DRAFT" ==  "true" ]]; then
  PR_ARG="$PR_ARG -d"
fi

COMMAND="hub pull-request \
  -b $DESTINATION_BRANCH \
  -h $SOURCE_BRANCH \
  --no-edit \
  $PR_ARG \
  || true"

echo "$COMMAND"

PR_URL=$(sh -c "$COMMAND")
if [[ "$?" != "0" ]]; then
  exit 1
fi

echo ${PR_URL}
echo "::set-output name=pr_url::${PR_URL}"