Add req.hostname

closes #2179

test/req.hostname.js

@@ -0,0 +1,138 @@
+
+var express = require('../')
+  , request = require('supertest')
+  , assert = require('assert');
+
+describe('req', function(){
+  describe('.hostname', function(){
+    it('should return the Host when present', function(done){
+      var app = express();
+
+      app.use(function(req, res){
+        res.end(req.hostname);
+      });
+
+      request(app)
+      .post('/')
+      .set('Host', 'example.com')
+      .expect('example.com', done);
+    })
+
+    it('should strip port number', function(done){
+      var app = express();
+
+      app.use(function(req, res){
+        res.end(req.hostname);
+      });
+
+      request(app)
+      .post('/')
+      .set('Host', 'example.com:3000')
+      .expect('example.com', done);
+    })
+
+    it('should return undefined otherwise', function(done){
+      var app = express();
+
+      app.use(function(req, res){
+        req.headers.host = null;
+        res.end(String(req.hostname));
+      });
+
+      request(app)
+      .post('/')
+      .expect('undefined', done);
+    })
+
+    it('should work with IPv6 Host', function(done){
+      var app = express();
+
+      app.use(function(req, res){
+        res.end(req.hostname);
+      });
+
+      request(app)
+      .post('/')
+      .set('Host', '[::1]')
+      .expect('[::1]', done);
+    })
+
+    it('should work with IPv6 Host and port', function(done){
+      var app = express();
+
+      app.use(function(req, res){
+        res.end(req.hostname);
+      });
+
+      request(app)
+      .post('/')
+      .set('Host', '[::1]:3000')
+      .expect('[::1]', done);
+    })
+
+    describe('when "trust proxy" is enabled', function(){
+      it('should respect X-Forwarded-Host', function(done){
+        var app = express();
+
+        app.enable('trust proxy');
+
+        app.use(function(req, res){
+          res.end(req.hostname);
+        });
+
+        request(app)
+        .get('/')
+        .set('Host', 'localhost')
+        .set('X-Forwarded-Host', 'example.com:3000')
+        .expect('example.com', done);
+      })
+
+      it('should ignore X-Forwarded-Host if socket addr not trusted', function(done){
+        var app = express();
+
+        app.set('trust proxy', '10.0.0.1');
+
+        app.use(function(req, res){
+          res.end(req.hostname);
+        });
+
+        request(app)
+        .get('/')
+        .set('Host', 'localhost')
+        .set('X-Forwarded-Host', 'example.com')
+        .expect('localhost', done);
+      })
+
+      it('should default to Host', function(done){
+        var app = express();
+
+        app.enable('trust proxy');
+
+        app.use(function(req, res){
+          res.end(req.hostname);
+        });
+
+        request(app)
+        .get('/')
+        .set('Host', 'example.com')
+        .expect('example.com', done);
+      })
+    })
+
+    describe('when "trust proxy" is disabled', function(){
+      it('should ignore X-Forwarded-Host', function(done){
+        var app = express();
+
+        app.use(function(req, res){
+          res.end(req.hostname);
+        });
+
+        request(app)
+        .get('/')
+        .set('Host', 'localhost')
+        .set('X-Forwarded-Host', 'evil')
+        .expect('localhost', done);
+      })
+    })
+  })
+})