merge_pr

set -e

function pr_label {
    REPO_URL=${1}
    PR=${2}
    REPO=${REPO_URL##https://github.com/}
    echo `curl -s https://api.github.com/repos/${REPO}/pulls/${PR} \
        | jq .head.label | tr -d '"'`
}

if [ $# == 1 ]; then
    PR=${1##*/}
    REPO_URL=${1%%/pull/${PR}}
elif [ $# == 2 ]; then
    REPO_URL=$1
    PR=$2
else
   echo "usage: $0 <repo_url> <pr_number>"
   echo "OR"
   echo "usage: $0 <pr_url>"
   exit 1
fi

REPO_BASE=${REPO_URL%.git}
PROJECT=${REPO_BASE##*/}
ASF_REPO_URL=https://git-wip-us.apache.org/repos/asf/${PROJECT}.git
WORKING_DIR=`mktemp -d`
CUR_DIR=`pwd`
USER_NAME=`git config user.name`
USER_EMAIL=`git config user.email`
ME="${USER_NAME} <${USER_EMAIL}>"
echo $PROJECT

cd ${WORKING_DIR}

git init
git remote add github ${REPO_URL}
git remote add asf ${ASF_REPO_URL}
git fetch github master

git fetch github pull/${PR}/head:github/pr/${PR}
git checkout master

if [ `git merge-base master github/pr/${PR}` != `git rev-parse HEAD` ]; then
   echo "The master branch is updated. Please rebase before the merge"
   cd ${CUR_DIR}
   rm -rf ${WORKING_DIR}
   exit 1
fi

LABEL=$(pr_label $REPO_URL $PR)

echo "============== CHANGES ==========================="
echo $(git rev-parse github/pr/${PR})$'\t\t'"github/pr/${PR}" | git fmt-merge-msg --log=5
echo "=================================================="

git merge --no-ff --no-edit github/pr/${PR}
cat <<EOF | git commit --amend --file -
Merge remote branch '${LABEL}'

This closes #${PR}

Signed-off-by: ${ME}

EOF

git show
echo "The merged PR for ${PROJECT} is in ${WORKING_DIR}"

cd ${CUR_DIR}