git hook for deploy

post-receive.sh

#!/bin/bash
TARGET="/home/git/intermediate_dir_for_build"
BUILD_DIR="$TARGET/build"
DEPLOY_DIR="/var/www/deploy_site_name"
GIT_DIR="/home/git/repo_name.git"
BRANCH="master"
REF_MATCH="refs/tags/"
umask 002
while read oldrev newrev ref
do
        # only checking out the master (or whatever branch you would like to deploy)
        if [[ "$ref" = "${REF_MATCH}"* ]]
        then
                echo "Ref $ref received. Deploying ${BRANCH} branch $DEPLOY_DIR"
                git --work-tree=$TARGET --git-dir=$GIT_DIR checkout -f $BRANCH               
                npm install
                npm run build
                cp -rf $BUILD_DIR/* $DEPLOY_DIR
        else
                echo "Ref $ref received. Doing nothing: only the ${REF_MATCH}* makes deploy"
        fi
done