deploy.bash

#!/bin/bash

function deploy {
  # Update the rsync target on the server
  rsync \
    -av \
    --delete \
    --delete-excluded \
    $rsync_ignore_list_param \
    $rsync_source/ $target:$rsync_target

  # Do everything else in a bash script
  ssh $target bash -s << ENDSSH
set -e

# Ensure the deploys folder exists
mkdir -p $deploys

# Copy the rsynced folder
deploydir=$deploys/$prefix$(date +%s)
cp -r $rsync_target \$deploydir

# Update the symlink to the latest deploy
symlink=$deploys/$name
rm -f \$symlink
ln -s \$deploydir \$symlink

# Cd into the deploy
cd \$deploydir

# Run some build steps
$build_cmd

# Restart the service
$restart_cmd

# Keep only the latest deploys
echo $deploys/$prefix* Only $keep
echo $deploys/$prefix* | tr ' ' '\n' | head -n -$keep | xargs rm -rf

ENDSSH
}

function rollback {
  ssh $target bash -s << ENDSSH
set -e

# Figure out which deploy to revert to
deploydir=\$(echo $deploys/$prefix* | tr ' ' '\n' | tail -n 2 | head -n 1)

# Update the symlink
symlink=$deploys/$name
rm -f \$symlink
ln -s \$deploydir \$symlink

# Restart the service
cd \$deploydir
$restart_cmd

# Delete the last deploy
ls -d $deploys/$prefix* | tail -n 1 | xargs rm -rf

echo Reverted to \$deploydir
ENDSSH
}

function usage {
  cat <<-END >&2
USAGE:
  $0 [-R] [-b cmd] [-i ignores] [-k #] [-n name] [-r cmd] [-s src] host [...]

  -b      command to perform build the deployed folder
  -d      path to a folder on the server where the deploys will reside,
          defaults to ~/deploys
  -i      path to a new-line separated list of files to ignore,
          defaults to [folder]/.rsyncignore
  -k      number of previous builds to keep, defaults to 3
  -n      project name, defaults to basename of the deployed foler path
  -r      command to restart service
  -R      rollback to the previous deploy instead of deploying
  -s      path to the deploy folder, defaults to \$PWD
  host  the ssh target defined in your ~/.ssh/config (see ssh_config(5))
END
  exit
}

while getopts "b:d:i:k:n:r:Rs:" opt; do
  case $opt in
    b)    opt_build=$OPTARG ;;
    d)    opt_deploys=$OPTARG ;;
    i)    opt_ignore=$OPTARG ;;
    k)    opt_keep=$OPTARG ;;
    n)    opt_name=$OPTARG ;;
    r)    opt_restart=$OPTARG ;;
    R)    opt_rollback=1 ;;
    s)    opt_bundle=$OPTARG ;;
    h|?)  usage ;;
  esac
done

rsync_source=${opt_bundle:-$PWD}
name=${opt_name:-$(basename $rsync_source)}
ignore_list=${opt_ignore:-$rsync_source/.rsyncignore}
deploys=${opt_deploys:-\~/deploys}
keep=${opt_keep:-3}
restart_cmd=${opt_restart:-echo No restart command defined}
build_cmd=${opt_build:-echo No build command defined}

rsync_target=$deploys/$name-rsync
prefix=$name-t

if [ -r "$ignore_list" ]; then
  rsync_ignore_list_param=--exclude-from=$ignore_list
else
  rsync_ignore_list_param=
fi

if (( $# < 1)); then
  usage
fi

# Quit on errors
set -e

shift $(( $OPTIND - 1 ))
while (( $# )); do
  target=$1

  if (( opt_rollback )); then
    rollback
  else
    deploy
  fi

  shift
done