js.py

# -*- coding: utf-8 -*-
'''
JavaScript Renderer for Salt

Example SLS file:

#!js

module.exports.wget = function () {
    return { pkg: ['installed'] };
};


Note that the code is executed with node -e - there is no __filename, __dirname and no way to include local modules.
You can either export a JSON or an object containing objects/functions returning objects.
'''

from __future__ import absolute_import

# Import python libs
import subprocess
import json

# Import salt libs
from salt._compat import string_types


def render(js, saltenv='base', sls='', **kws):
    if not isinstance(js, string_types):
        js = js.read()

    if js.startswith('#!'):
        js = js[(js.find('\n') + 1):]

    js = """var data = 
                (function (exports, module) {
                    """ + js + """
                    return Object.keys(exports).length && exports || module && module.exports || {};
                }({}, { exports: {} }));
            if(typeof data === 'object') {
                for(var k in data) {
                    switch(typeof data[k]) {
                        case 'function': data[k] = data[k](); break;
                    }
                }
                data = JSON.stringify(data);
            }
            console.log(data);
            
         """
    output = subprocess.check_output(["node", "-e", js])

    return json.loads(output)