post receive git hook that runs post_receive.rb if it exists in the repository

post-receive.sh

#!/bin/bash
# Shell script that should be installed on the origin server as post-receive hook

export GIT_SOURCE=$PWD

# Extract args and set environment variables for each ref pushed
while read oldrev newrev ref
do

  export BEFORE=$oldrev
  export AFTER=$newrev
  export REF=$ref
  export BRANCH=`echo $ref | cut -d/ -f3`

  echo "create tmp directory"
  export TMP_DIR=$(mktemp -d)

  echo "make a clone of the pushed branch"
  git clone --branch $BRANCH $GIT_SOURCE $TMP_DIR

  if [ -f $TMP_DIR/post_receive.rb ]; then
    echo "run post_receveive.rb"
    ( cd $TMP_DIR && ruby post_receive.rb )
  else
    echo "no post_receive.rb in this branch"
  fi

  echo "remove tmp directory"
  rm -rf $TMPDIR

done