Adding ability to set cookie path

lib/http-proxy/common.js

@@ -5,7 +5,7 @@ var common   = exports,
 
 var upgradeHeader = /(^|,)\s*upgrade\s*($|,)/i,
     isSSL = /^https|wss/,
-    cookieDomainRegex = /(;\s*domain=)([^;]+)/i;
+    cookieProps = ['domain', 'path'];
 
 /**
  * Simple Regex for testing if protocol is https
@@ -211,27 +211,30 @@ common.urlJoin = function() {
  *
  * @api private
  */
-common.rewriteCookieDomain = function rewriteCookieDomain(header, config) {
+common.rewriteCookieProperty = function rewriteCookieProperty(header, config, property) {
+  if(cookieProps.indexOf(property) === -1) //Property not supported
+    return header;
+
   if (Array.isArray(header)) {
     return header.map(function (headerElement) {
-      return rewriteCookieDomain(headerElement, config);
+      return rewriteCookieProperty(headerElement, config, property);
     });
   }
-  return header.replace(cookieDomainRegex, function(match, prefix, previousDomain) {
-    var newDomain;
-    if (previousDomain in config) {
-      newDomain = config[previousDomain];
+  return header.replace(new RegExp("(;\\s*" + property + "=)([^;]+)"), function(match, prefix, previousValue) {
+    var newValue;
+    if (previousValue in config) {
+      newValue = config[previousValue];
     } else if ('*' in config) {
-      newDomain = config['*'];
+      newValue = config['*'];
     } else {
-      //no match, return previous domain
+      //no match, return previous value
       return match;
     }
-    if (newDomain) {
-      //replace domain
-      return prefix + newDomain;
+    if (newValue) {
+      //replace value
+      return prefix + newValue;
     } else {
-      //remove domain
+      //remove value
       return '';
     }
   });

lib/http-proxy/passes/web-outgoing.js

@@ -84,12 +84,16 @@ module.exports = { // <--
    */
   writeHeaders: function writeHeaders(req, res, proxyRes, options) {
     var rewriteCookieDomainConfig = options.cookieDomainRewrite,
+        rewriteCookiePathConfig = options.cookiePathRewrite,
         preserveHeaderKeyCase = options.preserveHeaderKeyCase,
         rawHeaderKeyMap,
         setHeader = function(key, header) {
           if (header == undefined) return;
           if (rewriteCookieDomainConfig && key.toLowerCase() === 'set-cookie') {
-            header = common.rewriteCookieDomain(header, rewriteCookieDomainConfig);
+            header = common.rewriteCookieProperty(header, rewriteCookieDomainConfig, 'domain');
+          }
+          if (rewriteCookiePathConfig && key.toLowerCase() === 'set-cookie') {
+            header = common.rewriteCookieProperty(header, rewriteCookiePathConfig, 'path');
           }
           res.setHeader(String(key).trim(), header);
         };
@@ -98,6 +102,10 @@ module.exports = { // <--
       rewriteCookieDomainConfig = { '*': rewriteCookieDomainConfig };
     }
 
+    if (typeof rewriteCookiePathConfig === 'string') { //also test for ''
+      rewriteCookiePathConfig = { '*': rewriteCookiePathConfig };
+    }
+
     // message.rawHeaders is added in: v0.11.6
     // https://nodejs.org/api/http.html#http_message_rawheaders
     if (preserveHeaderKeyCase && proxyRes.rawHeaders != undefined) {

test/lib-http-proxy-passes-web-outgoing-test.js

@@ -298,6 +298,17 @@ describe('lib/http-proxy/passes/web-outgoing.js', function () {
         .to.contain('hello; domain=my.domain; path=/');
     });
 
+    it('rewrites path', function() {
+      var options = {
+        cookiePathRewrite: '/dummyPath'
+      };
+
+      httpProxy.writeHeaders({}, this.res, this.proxyRes, options);
+
+      expect(this.res.headers['set-cookie'])
+        .to.contain('hello; domain=my.domain; path=/dummyPath');
+    });
+
     it('rewrites domain', function() {
       var options = {
         cookieDomainRewrite: 'my.new.domain'