AWS EB-Extension to install PhantomJS

gistfile1.txt

files:
  "/opt/elasticbeanstalk/hooks/appdeploy/pre/04_install_phantomjs":
    mode: "000777"
    owner: root
    group: root
    content: |
      #!/usr/bin/env bash

      set -xe

      EB_SCRIPT_DIR=$(/opt/elasticbeanstalk/bin/get-config container -k script_dir)
      EB_APP_STAGING_DIR=$(/opt/elasticbeanstalk/bin/get-config container -k app_staging_dir)
      EB_APP_USER=$(/opt/elasticbeanstalk/bin/get-config container -k app_user)
      EB_SUPPORT_DIR=$(/opt/elasticbeanstalk/bin/get-config container -k support_dir)

      . $EB_SUPPORT_DIR/envvars


      command -v phantomjs >/dev/null 2>&1 || {
        echo "PhantomJS needs to be installed now";
        wget https://bitbucket.org/ariya/phantomjs/downloads/phantomjs-1.9.8-linux-x86_64.tar.bz2
        mkdir -p /opt/phantomjs
        bzip2 -d phantomjs-1.9.8-linux-x86_64.tar.bz2
        tar -xvf phantomjs-1.9.8-linux-x86_64.tar --directory /opt/phantomjs/ --strip-components 1
        ln -s /opt/phantomjs/bin/phantomjs /usr/bin/phantomjs

        echo "PhantomJS is installed successfully";
      }

Hi there, I'm trying to install Phantom JS on a PHP version of Elastic beanstalk. Not having much luck however. Get this error:
Command failed on instance. Return code: 1 Output: (TRUNCATED)...-config container -k app_user + EB_APP_USER=webapp ++ /opt/elasticbeanstalk/bin/get-config container -k support_dir + EB_SUPPORT_DIR= + . /envvars /opt/elasticbeanstalk/hooks/appdeploy/pre/04_install_phantomjs: line 10: /envvars: No such file or directory. Hook /opt/elasticbeanstalk/hooks/appdeploy/pre/04_install_phantomjs failed. For more detail, check /var/log/eb-activity.log using console or EB CLI.

Any ideas?