FastCGI server for Node.js

node_fcgi.js

var net = require('net'),
	querystring = require('querystring');

var TYPES = {
	FCGI_BEGIN_REQUEST     : 1,
	FCGI_ABORT_REQUEST     : 2,
	FCGI_END_REQUEST       : 3,
	FCGI_PARAMS            : 4,
	FCGI_STDIN             : 5,
	FCGI_STDOUT            : 6,
	FCGI_STDERR            : 7,
	FCGI_DATA              : 8,
	FCGI_GET_VALUES        : 9,
	FCGI_GET_VALUES_RESULT : 10,
	FCGI_UNKNOWN_TYPE      : 11
}

var mix = function(des, src, map){
	map = map || function(d, s, i){
		if(!(des[i] || (i in des))){
			return s;
		}
		return d;
	}
	if(map === true){
		map = function(d,s){
			return s;
		}
	}

	for (i in src) {
		des[i] = map(des[i], src[i], i, des, src);
		if(des[i] === undefined) delete des[i];
	}
	return des;
};

function getRcds(data, cb){
	var rcds = [],
		start = 0,
		length = data.length;
	return function (){
		if(start >= length){
			cb && cb(rcds);
			rcds = null;
			return;
		}
		var end = start + 8,
			header = data.slice(start, end),
			version = header[0],
			type    = header[1],
			requestId = (header[2] << 8) + header[3],
			contentLength = (header[4] << 8) + header[5],
			paddingLength = header[6];
		start = end + contentLength + paddingLength;

		var body = contentLength ? data.slice(end, contentLength) : null;
		rcds.push([type, body, requestId]);

		return arguments.callee();
	}
}

function parseParams(body){
	var j = 0,
		params = {},
		length = body.length;
	while(j < length){
		var name,
			value,
			nameLength,
			valueLength;
		if(body[j] >> 7 == 1){
			nameLength = ((body[j++] & 0x7f) << 24) + (body[j++] << 16) + (body[j++] << 8) + body[j++];
		} else {
			nameLength = body[j++];
		}

		if(body[j] >> 7 == 1){
			valueLength = ((body[j++] & 0x7f) << 24) + (body[j++] << 16) + (body[j++] << 8) + body[j++];
		} else {
			valueLength = body[j++];
		}

		var ret = body.asciiSlice(j, j + nameLength + valueLength);
		name = ret.substring(0, nameLength);
		value = ret.substring(nameLength);
		params[name] = value;

		j += (nameLength + valueLength);
	}
	return params;
}

var res = (function(){
	var MaxLength = Math.pow(2, 16);

	function buffer0(len){
		return new Buffer((new Array(len + 1)).join('\u0000'));
	};

	function writeStdout(data){
		var rcdStdoutHd = new Buffer(8),
			contendLength = data.length,
			paddingLength = 8 - contendLength % 8;

		rcdStdoutHd[0] = 1;
		rcdStdoutHd[1] = TYPES.FCGI_STDOUT;
		rcdStdoutHd[2] = 0;
		rcdStdoutHd[3] = 1;
		rcdStdoutHd[4] = contendLength >> 8;
		rcdStdoutHd[5] = contendLength;
		rcdStdoutHd[6] = paddingLength;
		rcdStdoutHd[7] = 0;

		return Buffer.concat([rcdStdoutHd, data, buffer0(paddingLength)]);
	};

	function writeHttpHead(){
		return writeStdout(new Buffer("HTTP/1.1 200 OK\r\nContent-Type:text/html; charset=utf-8\r\nConnection: close\r\n\r\n"));
	}

	function writeHttpBody(bodyStr){
		var bodyBuffer = [],
			body = new Buffer(bodyStr);
		for(var i = 0, l = body.length; i < l; i += MaxLength + 1){
			bodyBuffer.push(writeStdout(body.slice(i, i + MaxLength)));
		}
		return Buffer.concat(bodyBuffer);
	}

	function writeEnd(){
		var rcdEndHd = new Buffer(8);
		rcdEndHd[0] = 1;
		rcdEndHd[1] = TYPES.FCGI_END_REQUEST;
		rcdEndHd[2] = 0;
		rcdEndHd[3] = 1;
		rcdEndHd[4] = 0;
		rcdEndHd[5] = 8;
		rcdEndHd[6] = 0;
		rcdEndHd[7] = 0;
		return Buffer.concat([rcdEndHd, buffer0(8)]);
	}

	return function(data){
		return Buffer.concat([writeHttpHead(), writeHttpBody(data), writeEnd()]);
	};
})();

var visitors = 0;
var server = net.createServer();
server.listen('/tmp/node_fcgi.sock');
server.on('connection', function(sock){
	visitors++;
	sock.on('data', function(data){
		var params = {};
		getRcds(data, function(rcds){
			for(var i = 0, l = rcds.length; i < l; i++){
				var bodyData = rcds[i],
					type = bodyData[0],
					body = bodyData[1];
				if(body && (type === TYPES.FCGI_PARAMS || type === TYPES.FCGI_GET_VALUES || type === TYPES.FCGI_GET_VALUES_RESULT)){
					mix(params, parseParams(body));					
				}
			}

			var querys = querystring.parse(params.QUERY_STRING);
			var ret = res('欢迎你，' + (querys.name || '亲爱的朋友') + '！你是本站第' + visitors + '位用户哦~');
			sock.write(ret);
			ret = null;
			sock.end();
		})();
	});
});