构建web应用

var http = require(‘http‘);
http.createServer(function(req, res){
    res.writeHeader(200, {Content-Type : ‘text/plain‘});
    res.end(‘hello world!‘);
}).listen(80);

function(req, res){
    var method = req.method;
    if(method === ‘POST‘){
    }else if(method === ‘GET‘){
    }else if(method === ‘DELETE‘){
    }else if(method === ‘PUT‘){
    }else{
    }
}

var url = require(‘url‘);
var fs = require(‘fs‘);
function(req, res){
    var pathname = url.parse(req.url).pathname;
    fs.readFile(path.join(ROOT, pathname), function(err, file){
        if(err){
            res.writeHeader(404);
            res.end(‘not Found File‘);
            return;
        }
        res.writeHeader(200);
        res.end(file);
    });
}

var url = require(‘url‘);
var query = url.parse(req.url, true).query;//{foo : ‘aaa‘, baz : ‘bbb‘}
req.query = query;
handle(req, res);

function parseCookie(cookie){
    var cookies = {};
    if(!cookie){
        return cookies;
    }
    var list = cookie.split(‘;‘);
    for(var i = 0,len = list.length;i < len;i++){
        var pair = list[i].split(‘=‘);
        cookies[pair[0].trim()] = pair[1];
    }
    return cookies;
};
req.cookies = parseCookie(req.headers.cookie);
handle(req, res);
 
function serialize(name, value, options){
    var pairs = [name+‘=‘+value];
    if(options.expires){
        pairs.push(‘Expires=‘+options.expires.toUTCString());
    }
    if(options.maxAge){
        pairs.push(‘Max-Age=‘+options.maxAge);
    }
    if(options.path){
        pairs.push(‘Path=‘+options.path);
    }
    if(options.domain){
        pairs.push(‘Domain=‘+options.domain);
    }
    if(options.httpOnly){
        pairs.push(‘HTTPOnly‘);
    }
    if(options.secure){
        pairs.push(‘Secure‘);
    }
    return pares.join(‘;‘);
}
 
res.writeHeader(‘Set-Cookie‘, serialize({isVisit : 1}));

var hasBody = function(req){
    return ‘transfer-encoding‘ in req.Headers || ‘content-length‘ in req.Headers; 
}
 
function(req, res){
    if(hasBody(req)){
        var buffers = [];
        req.on(‘data‘, function(chunk){
            buffers.push(chunk);
        });
        req.on(‘end‘, function(){
            req.rawBody = Buffer.concat(buffers).toString();
            handle(req, res);
        });
    }else{
        handle(req, res);
    }
};

req.body = querystring.parse(req.rawBody);
 
var mime = function(req){
    return req.headers[‘content-type‘].split(‘;‘)[0] || ‘‘;
}
 
var xml2js = require(‘xml2js‘);
var handle = function(req, res){
    if(mime(req) === ‘application/json‘){
        try{
            req.body = JSON.parse(req.rowBody);
        }catch(){
            res.writeHeader(‘400‘);
            res.end(‘invalid json‘);
            return;
        }
    }
    if(mime(req) === ‘application/xml‘){
        xml2js.parseString(req,rawBody, function(err, xml){
            if(err){
            }else{
                req.body = xml;
            }
        });
    }
};

var formidable = require(‘formidable‘);
function(req, res){
    if(hasBody(req)){
        if(mime(req) === ‘multipart/form-data‘){
            var form = new formidable.IncomingForm();
            form.parse(req, function(err, fields, files){
                req.body = fields;
                req.files = files;
                handle(req, res);
            });
        }
    }
}

var bytes = 1024;
 
function(req, res){
    var received = 0;
    var len = req.headers[‘content-length‘]?parseInt(req.headers[‘content-length‘], 10):null;
    if(len > bytes){
        res.writeHeader(413);
        res.end;
        return;
    }
 
    res.on(‘data‘, function(chunk){
        received += chunk.length;
        if(received > bytes){
            req.destroy();
        }
    });
    
    handle(req, res);
};