perform_release/prepare_release.sh
#######################################################################
## Copyright (c) 2016-2017 Contributors to the Eclipse Foundation
##
## See the NOTICE file(s) distributed with this work for additional
## information regarding copyright ownership.
##
## Licensed under the Apache License, Version 2.0 (the "License");
## you may not use this file except in compliance with the License.
## You may obtain a copy of the License at
##
##     http://www.apache.org/licenses/LICENSE-2.0
##
## Unless required by applicable law or agreed to in writing, software
## distributed under the License is distributed on an "AS IS" BASIS,
## WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
## See the License for the specific language governing permissions and
## limitations under the License.
#######################################################################
#set -v

##################################
# Specify the following variables
##################################

# requirements for versions:
#   - for BND: dash must come before a classifier, such as RC1 (e.g. 1.0-RC1 is valid while 1.0RC1 is invalid)
#RELEASE_VERSION=1.0-RC1
#DEV_VERSION=1.0-SNAPSHOT
#GIT_USER='Kevin Sutter'
#GIT_EMAIL='kwsutter@gmail.com'
ORIGIN_REMOTE_REPO=origin # - the name of the upstream repository to push changes to. It should be the main repository, not a fork
BASE_REVISION=master # branch, tag or revision to make release from

# try to read in these variables from a release.conf file
if [ -e release.conf ]; then
    source release.conf
fi

# check that we have all variables, noting each one that is missing
declare -a release_vars=("RELEASE_VERSION" "DEV_VERSION" "GIT_USER" "GIT_EMAIL" "ORIGIN_REMOTE_REPO" "BASE_REVISION")
declare -a missing_vars=()
for v in "${release_vars[@]}"
do
    # echo "Checking ${v}=${!v}"
    if [ "X${!v}" = "X" ]; then
        echo "${v} is not defined"
        missing_vars+=("${v}")
    fi
done
if [ ${#missing_vars[@]} != 0 ]; then
    echo "ERROR: the following required variables are not defined: ${missing_vars[@]}"
    exit 1
fi

# Specify derived variables

BRANCH=branch_$RELEASE_VERSION
TAG=$RELEASE_VERSION

# set git identity

git config user.name "$GIT_USER"
git config user.email "$GIT_EMAIL"

# delete release branch and tag

git checkout "$BASE_REVISION"
git reset --hard
git clean -f
git branch -D "$BRANCH"
git tag -d "$TAG" ## it's OK if tag cannot be found
# create and checkout release branch

git branch "$BRANCH"
git checkout "$BRANCH"

# prepare release

mvn --batch-mode -DreleaseVersion=$RELEASE_VERSION -DdevelopmentVersion=$DEV_VERSION -Dtag=$TAG release:clean release:prepare

# don't continue if the mvn command fails or aborted
if [[ x$? != x0 ]]
  then
    echo ERROR, aborting
    exit
fi

# publish the release TAG
### If this fails because the tag already exists in the remote repo,
### you can delete the tag with `git tag -d "$TAG" && git push origin :refs/tags/"$TAG"`

git push "$ORIGIN_REMOTE_REPO" "$TAG"

# revert git identity

git config --unset user.name
git config --unset user.email
