Start GeoServer with GeoNode extensions

def start_geoserver(options):
    """
    Start GeoServer with GeoNode extensions
    """

    from geonode.settings import OGC_SERVER 
    GEOSERVER_BASE_URL = OGC_SERVER['default']['LOCATION']

    url = "http://localhost:8080/geoserver/"
    if GEOSERVER_BASE_URL != url:
        print 'your GEOSERVER_BASE_URL does not match %s' % url
        sys.exit(1)

    download_dir = path('downloaded').abspath()
    jetty_runner = download_dir / os.path.basename(JETTY_RUNNER_URL)
    data_dir = path('geoserver/data').abspath()
    web_app = path('geoserver').abspath()
    log_file = path('geoserver/jetty.log').abspath()

    # @todo - we should not have set workdir to the datadir but a bug in geoserver
    # prevents geonode security from initializing correctly otherwise
    with pushd(data_dir):
        sh(('java -Xmx512m -XX:MaxPermSize=256m'
            ' -DGEOSERVER_DATA_DIR=%(data_dir)s'
            # workaround for JAI sealed jar issue and jetty classloader
            ' -Dorg.eclipse.jetty.server.webapp.parentLoaderPriority=true'
            ' -jar %(jetty_runner)s'
            ' --log %(log_file)s'
            ' --path /geoserver %(web_app)s'
            ' > /dev/null &' % locals()
          ))

    info('Starting GeoServer on %s' % url)

    # wait for GeoServer to start
    started = waitfor(url)
    info('The logs are available at %s' % log_file)

    if not started:
        # If applications did not start in time we will give the user a chance
        # to inspect them and stop them manually.
        info(('GeoServer never started properly or timed out.'
              'It may still be running in the background.'))
        sys.exit(1)