Build and deploy jekyll site to gh-pages branch

deploy-to-gh-pages.sh

#!/bin/bash
set -e

# based on https://gist.github.com/cobyism/4730490

DIST_FOLDER='_site'
PUBLISH_BRANCH='gh-pages'
REMOTE='origin'
GIT_USER=`git config user.name`

if [ -z "$1" ]
then
  echo
  echo "Usage: deploy-to-gh-pages [release number]"
  echo
  echo "e.g."
  echo
  echo "    deploy-to-gh-pages 1"
  exit 1
fi

RELEASE="release$1"
echo
echo "Creating branch ${RELEASE}"

git checkout origin/dev > /dev/null
git checkout -b ${RELEASE} > /dev/null

echo
echo "Installing dependencies"
bundle > /dev/null

echo
echo "Building Jekyll app"
bundle exec jekyll build > /dev/null

echo
echo "Committing _site into branch ${RELEASE}"
git add --force _site && git commit ${DIST_FOLDER} -m "Build $1 of ${DIST_FOLDER} by ${GIT_USER}" > /dev/null

echo
echo "Pushing a copy of ${RELEASE} branch to remote ${REMOTE}"
git push ${REMOTE} ${RELEASE} --force > /dev/null

## Can't force push this, so we delete the branch then push newly made one.
echo
echo "Removing existing ${PUBLISH_BRANCH} branch on remote ${REMOTE}"
git push ${REMOTE} ":${PUBLISH_BRANCH}"

echo
echo "Moving ${DIST_FOLDER} files to / in branch ${PUBLISH_BRANCH}"
git subtree push --prefix ${DIST_FOLDER} ${REMOTE} ${PUBLISH_BRANCH}

echo
echo "Returning to dev branch"
git checkout dev