add support for CROS

lib/requestHandler.js

@@ -27,7 +27,8 @@ var handleRule = {
 
 function userRequestHandler(req,userRes){
     var host = req.headers.host,
-        path = url.parse(req.url).pathname,
+        urlPattern = url.parse(req.url),
+        path       = urlPattern.path,
         ifLocalruleMatched = false;
 
     console.log(color.green("\nreceived request to : " + host + path));
@@ -37,6 +38,13 @@ function userRequestHandler(req,userRes){
         in https server : /work/alibaba
     */
 
+    if(req.method == "OPTIONS"){
+        console.log("==>OPTIONS req for CROS, will allow all");
+        userRes.writeHead(200,mergeCROSHeader(req.headers)); //remove any cache related header, add crossdomain headers
+        userRes.end();
+        return;
+    }
+
     for(var index in handleRule.map){
         var rule = handleRule.map[index];
 
@@ -58,7 +66,6 @@ function userRequestHandler(req,userRes){
             if(fs.existsSync(targetLocalfile)){
                 try{
                     var fsStream = fs.createReadStream(targetLocalfile);
-                    userRes.writeHead(200,{"cache-control":"max-age=0"}); //remove any cache related header
                     fsStream.pipe(userRes);
                     ifLocalruleMatched = true;
                     break;
@@ -79,24 +86,24 @@ function userRequestHandler(req,userRes){
         var ifHttps = !!req.connection.encrypted && !/http:/.test(req.url);
 
         var options = {
-            hostname : req.headers.host,
-            port     : req.port || (ifHttps ? 443 : 80),
+            hostname : urlPattern.hostname || req.headers.host,
+            port     : urlPattern.port || req.port || (ifHttps ? 443 : 80),
             path     : path,
             method   : req.method,
             headers  : req.headers
         };
 
         var proxyReq = (ifHttps ? https : http).request(options, function(res) {
-            userRes.writeHead(res.statusCode,res.headers);
+            userRes.writeHead(res.statusCode,mergeCROSHeader(req.headers,res.headers));
             res.pipe(userRes);
         });
 
         proxyReq.on("error",function(e){
-            console.log("err with request :" + req.url);
+            console.log("err with request :" + e.code + "  " + req.url);
             userRes.end();
         });
-        proxyReq.end();
-    
+
+        req.pipe(proxyReq);
     }
 }
 
@@ -147,7 +154,6 @@ function connectReqHandler(req, socket, head){
                         socket.write('HTTP/' + req.httpVersion + ' 200 OK\r\n\r\n', 'UTF-8', function() {
                             conn.pipe(socket);
                             socket.pipe(conn);
-
                         });
                     });   
 
@@ -177,6 +183,18 @@ function setRules(newRule){
     }
 }
 
+// https://developer.mozilla.org/en-US/docs/Web/HTTP/Access_control_CORS
+function mergeCROSHeader(reqHeader,originHeader){
+    var targetObj = originHeader || {};
+
+    targetObj["Access-Control-Allow-Credentials"] = "true";
+    targetObj["Access-Control-Allow-Origin"]      = reqHeader['origin'] || "-___-||";
+    targetObj["Access-Control-Allow-Methods"]     = "GET, POST, PUT";
+    targetObj["Access-Control-Allow-Headers"]     = reqHeader['access-control-request-headers'] || "-___-||";
+
+    return targetObj;
+}
+
 module.exports.userRequestHandler = userRequestHandler;
 module.exports.connectReqHandler  = connectReqHandler;
 module.exports.setRules           = setRules;