'Read the relevant GET vars for the timeplot
@param r: the S3Request
@param resource: the target S3Resource'

@staticmethod
def get_options(r, resource):

    report_vars = ('timestamp', 'start', 'end', 'slots', 'fact', 'baseline', 'rows', 'cols')
    get_vars = dict(((k, v) for (k, v) in r.get_vars.iteritems() if (k in report_vars)))
    report_options = resource.get_config('timeplot_options', {})
    defaults = report_options.get('defaults', {})
    if (not any(((k in get_vars) for k in report_vars))):
        get_vars = defaults
    else:
        optional = ('timestamp', 'fact', 'baseline', 'rows', 'cols')
        for opt in optional:
            if ((opt not in get_vars) and (opt in defaults)):
                get_vars[opt] = defaults[opt]
    return (report_vars, get_vars)
