Joyent's NodeJS post-receive script.

post-receive.sh

#!/bin/bash -
# The "post-receive" script is run after receive-pack has accepted a pack
# and the repository has been updated.  It is passed arguments in through
# stdin in the form
#  <oldrev> <newrev> <refname>
# For example:
#  aa453216d1b3e49e7f6f98441fa56946ddcd6a20 68f7abf4e6f922807889f52bc043ecd31b79f814 refs/heads/master

#set -x

# This script is specific to the node-service. It checkouts out an updated
# version of the software and updates the SMF config to run it.

read oldrev newrev refname



function rollbackToDefault() {
  local log=$1

  echo
  echo "Rolling back to default server."

  start_state=$(svcs -H -o state node-service)
  if [ "$start_state" != "disabled" ]; then
    svcadm disable -s node-service
  fi

  svccfg import /opt/nodejs/default_server/default-server.xml

  # Long sleep to attempt to break out of "Restarting too quickly, changing
  # state to maintenance." from svc.startd.
  if [ "$start_state" == "maintenance" ]; then
    sleep 10
  fi

  # Give it a little bit to crash, necessary because our service "start" method
  # returns immediately.
  svcadm enable -s node-service
  sleep 1

  if [ "$(svcs -H -o state node-service)" != "online" ]; then
    echo "Rollback failed. Please report this to support@joyent.com."
    echo "* * *"
    tail -10 $log
    echo "* * *"
  else
    echo "Rollback succeeded."
  fi
}



svcadm disable -s node-service
if [ "`svcs -H -o state node-service`" != "disabled" ]; then
  echo "Failed to disable current node-service."
  exit 1
fi

# Get the short version of the sha1 tag.
rev=`echo $newrev | cut -c-6`
date=`date +%Y%m%d%H%M%S`
log="/var/svc/log/site-node-service:default.log"

service_dir="/home/node/node-service"
releases_dir="$service_dir/releases"
current_dir="$service_dir/current"
profile="$service_dir/profile"
dir="$releases_dir/$date"

if [ -d $releases_dir ]; then
  last_release=`ls $releases_dir | grep -v xml | tail -1`
fi

mkdir -p $releases_dir

# make sure the service profile is existing
if ! [ -f "$profile" ]; then
  ln -s /opt/nodejs/service-profile $profile
fi

unset GIT_DIR
unset GIT_WORK_TREE

#
# Poor man's git-archive. Why? git-submodules suck.
#
git clone /home/node/repo $dir >& /dev/null
cd $dir
git submodule update --init --recursive >& /dev/null
if ! [ -f $dir/server.js ]; then
  ( echo
    echo "Please add a server.js file to the root of your repo before pushing."
    echo "Cannot start node service without it."
    echo
  ) >&2
  exit 1
fi


# Figure out which version of Node this revision wants to be running.
nodeversion=`/opt/nodejs/get-node-version $dir`

# Build and install the updated SMF manifest for the node service.
manifest="$releases_dir/$date.xml"
gsed -e "s/@@NODEVERSION@@/$nodeversion/g" \
     -e "s/@@REV@@/$rev/g" \
     -e "s#@@DIR@@#$dir#g" \
     -e "s/@@VERSION@@/$date/g" \
      /opt/nodejs/node-service-manifest.xml.in > $manifest
svccfg import $manifest
svccfg -s node-service:default refresh

# The current dir isn't referenced in the node-service-manifest
# it's just for convenience.
rm -f $current_dir

# Give it a little bit to crash, necessary because our service "start" method
# returns immediately.
echo "Starting node $nodeversion..."
svcadm enable -s node-service
sleep 1

if [ "$(svcs -H -o state node-service)" == "online" ]; then
  echo "Successful"
  ln -s $dir $current_dir
else
  echo
  echo "Failed to start new server."
  echo
  echo "* * * tail of '$log' * * *"
  tail -50 $log
  echo "* * *"

  cd $releases_dir
  rm $manifest
  rm -rf $dir

  # Rollback
  if [ ! -z $last_release ]; then
    echo
    echo "Rolling back to $last_release ... (please wait)"

    original_state=$(svcs -H -o state node-service)
    svcadm disable -s node-service

    # Setup the last service config (my understanding is that this effectively
    # clears any maintenance state as well).
    dir="$releases_dir/$last_release"
    manifest="$dir.xml"
    svccfg import $manifest

    # Long sleep to attempt to break out of "Restarting too quickly, changing
    # state to maintenance." from svc.startd.
    if [ "$original_state" == "maintenance" ]; then
      sleep 10
    fi

    # Give it a little bit to crash, similar awful race as above.
    svcadm enable -s node-service
    sleep 1

    if [ "$(svcs -H -o state node-service)" != "online" ]; then
      echo "Rollback failed (old server did not start properly)."
      echo "* * *"
      tail -10 $log
      echo "* * *"
    else
      echo "Rollback succeeded."
      ln -s $dir $current_dir
    fi
  else
    rollbackToDefault $log
  fi
fi