[test] add test for selfHandleRequest and remove modifyResponse as se…

…lfHandleRequest is the only way that functionality works

.travis.yml

@@ -1,6 +1,7 @@
 sudo: false
 language: node_js
 node_js:
+  - "4"
   - "6"
   - "8"
 script:

README.md

@@ -377,7 +377,6 @@ proxyServer.listen(8015);
 *  **timeout**: timeout (in millis) for incoming requests
 *  **followRedirects**: true/false, Default: false - specify whether you want to follow redirects
 *  **selfHandleRequest** true/false, if set to true, none of the webOutgoing passes are called and its your responsibility ro appropriately return the response by listening and acting on the `proxyRes` event
-*  **modifyResponse**: do not pipe proxyRes to res, so you can respond to client with your own response. It still goes through all out going web passes unlike selfHandleRequest
 *  **buffer**: stream of data to send as the request body.  Maybe you have some middleware that consumes the request stream before proxying it on e.g.  If you read the body of a request into a field called 'req.rawbody' you could restream this field in the buffer option:
 
     ```
@@ -487,13 +486,16 @@ proxy.close();
 
 ### Miscellaneous
 
+If you want to handle your own response after receiving the proxyRes, you can do
+so with `selfHandleResponse`
+
 ### Modify response
 
 ```
 
     var option = {
-        target: target,
-        modifyResponse : true
+      target: target,
+      selfHandleResponse : true
     };
     proxy.on('proxyRes', function (proxyRes, req, res) {
         var body = new Buffer('');

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

@@ -182,7 +182,7 @@ module.exports = {
           if (server) server.emit('end', req, res, proxyRes);
         });
         // We pipe to the response unless its expected to be handled by the user
-        if (!options.selfHandleResponse && !options.modifyResponse) proxyRes.pipe(res);
+        if (!options.selfHandleResponse) proxyRes.pipe(res);
       } else {
         if (server) server.emit('end', req, res, proxyRes);
       }

package.json

@@ -18,6 +18,7 @@
   },
   "devDependencies": {
     "async": "^2.0.0",
+    "concat-stream": "^1.6.2",
     "expect.js": "~0.3.1",
     "mocha": "^3.5.3",
     "nyc": "^11.7.1",

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

@@ -1,6 +1,8 @@
 var webPasses = require('../lib/http-proxy/passes/web-incoming'),
     httpProxy = require('../lib/http-proxy'),
     expect    = require('expect.js'),
+    concat    = require('concat-stream'),
+    async     = require('async'),
     url       = require('url'),
     http      = require('http');
 
@@ -316,6 +318,44 @@ describe('#createProxyServer.web() using own http server', function () {
     http.request('http://127.0.0.1:8086', function() {}).end();
   });
 
+  it('should proxy the request and provide and respond to manual user response when using modifyResponse', function(done) {
+    var proxy = httpProxy.createProxyServer({
+      target: 'http://127.0.0.1:8080',
+      selfHandleResponse: true
+    });
+
+    function requestHandler(req, res) {
+      proxy.once('proxyRes', function (proxyRes, pReq, pRes) {
+        proxyRes.pipe(concat(function (body) {
+          expect(body.toString('utf8')).eql('Response');
+          pRes.end(Buffer.from('my-custom-response'));
+        }))
+      });
+
+      proxy.web(req, res);
+    }
+
+    var proxyServer = http.createServer(requestHandler);
+
+    var source = http.createServer(function(req, res) {
+      res.end('Response');
+    });
+
+    async.parallel([
+      next => proxyServer.listen(8086, next),
+      next => source.listen(8080, next)
+    ], function (err) {
+      http.get('http://127.0.0.1:8086', function(res) {
+        res.pipe(concat(function(body) {
+          expect(body.toString('utf8')).eql('my-custom-response');
+          source.close();
+          proxyServer.close();
+          done();
+        }));
+      }).once('error', done);
+    })
+  });
+
   it('should proxy the request and handle changeOrigin option', function (done) {
     var proxy = httpProxy.createProxyServer({
       target: 'http://127.0.0.1:8080',