node-ursa/lib/config.js

A front end development workbench with server/https/template engine/optimization tools support

/**
 * config.js
 *
 * changelog
 * 2013/11/02:add "defaultHttpPort" and "defaultHttpsPort" properties to config.
 * 
 * @author yinyong#sogou-inc.com
 * @version 0.0.2
 */

var fs = require("fs");
var path = require("path");
var utils = require("./utils");

var manifestFile = "./manifest.json";
/**
 * 同步方法，实时从manifest中获取配置信息。
 * 如果environment为空，优先从local对象中取值，取不到则尝试从
 * 直接对象中取值；如果非空，则从对应子对象中取值，如：
 * <code>
 * {
 *     "static_prefix":".",
 *     "local":{
 *         "static_prefix":"./"
 *     },
 *     "online":{
 *         "static_prefix":"../"
 *     }
 * }
 * </code>
 *
 * 则get("static_prefix")=="./"，而get("static_prefix","online")=="../"。
 * 搜索不到则返回undefined。
 *
 * @param  {String} key 配置名称
 * @param  {String} environment 搜索位置
 * @return {Object}     配置值
 */
var getConfig = function(key, environment) {
    if (!utils.isString(key)) {
        console.error("key MUST BE a string,but it's a %s".error, typeof key);
        return;
    }

    try {
        var content = fs.readFileSync(manifestFile, {
            encoding: 'utf-8'
        });
        content = utils.rmComment(content);
        var json = JSON.parse(content);
        //从里向外搜索
        //environment为null/undefined时优先取local内的值
        if(!environment){
            return json["local"]?((undefined===json["local"][key])?json[key]:json["local"][key]):json[key];
        }else{
            return json[environment]?((undefined===json[environment][key])?json[key]:json[environment][key]):json[key];
        }
    } catch (e) {
        console.error("[EMERGENCY]config-get(%s):%s\r\nPlease check your manifest.json.".error,key, e);
    }
}

var _config = {
    manifestFile: manifestFile,
    //set template dir configure
    templateDir: getConfig("template_dir") || ("." + path.sep + "template"),
    staticDir: "." + path.sep + "static",
    dataDir: "." + path.sep + "_data",
    templateSuffix: "tpl",
    accessSuffix: "ut",
    defaultHttpPort:8899,
    defaultHttpsPort:2443,
    get: function(key, proj) {
        return getConfig(key, proj);
    }
};

module.exports = _config;