node 后台ajax文件(同时支持http、https)

var http = require("http"),

    Url = require("url"),

    querystring = require('querystring');



// 默认值

function defaults(url){

    return {

        // 如果返回false可以取消本次请求

        beforeSend: function(req){},

        complete: function(req){},

        data: '', // Object, String

        dataType: 'html',

        error: function(){},

        headers: {}, // {k:v, ...}

        statusCode: {},

        success: function(data){},

        timeout: 10,

        type: 'GET', // GET, POST

        url: url

    };

}



function ajax( settings ){

    // ajax(settings)

    if( typeof settings === "object" ) {

        // 处理默认值继承

         // todo ...



    }

    

    var params = Url.parse(settings.url, true);

    // params 解析出来的参数如下

    // {

    // "protocol":"http:",

    // "slashes":true,

    // "host":"localhost:3000",

    // "port":"3000",

    // "hostname":"localhost",

    // "href":"http://localhost:3000/?d=1",

    // "search":"?d=1",

    // "query":{"d":"1"},

    // "pathname":"/",

    // "path":"/?d=1"

    // }



    var options = {

        host: params.hostname,

        port: params.port || 80, //80:http请求 443:https请求

        path: params.path,

        method: settings.type,

        headers:{

            'Content-Type':'application/x-www-form-urlencoded',

            'Content-Length': settings.data ? settings.data.length : 0

        }

    };



    if(settings.cookie) options.headers['Cookie'] = settings.cookie;



    var req = http.request(options, function(res) {

        var data = '';

        res.on('data', function(chunk) {

            data += chunk;

        }).on('end', function(){

            if(    settings.dataType === "json" ) {

                try {

                    data = JSON.parse(data);

                } catch(e) {

                    data = null;

                }

            }

            settings.success(data);

            settings.complete(req);

        });

    }).on('error', function(e) {

        settings.error(e);

    });



    if( typeof settings.beforeSend === "function" ) {

        if ( !settings.beforeSend(req) ) {

            settings.complete(req);

            req.end();

            return false;

        }

    }



    if( settings.type === "POST" ) {

        req.write(settings.data);

    }



    req.setTimeout(settings.timeout);

    req.end();

}



exports.ajax = ajax;