Accept multiple callbacks to app.use()

fixes #2224

History.md

@@ -1,6 +1,7 @@
 unreleased
 ==========
 
+  * accept multiple callbacks to `app.use()`
   * add explicit "Rosetta Flash JSONP abuse" protection
     - previous versions are not vulnerable; this is just explicit protection
   * catch errors in multiple `req.param(name, fn)` handlers

lib/application.js

@@ -147,41 +147,49 @@ app.handle = function(req, res, done) {
  * @api public
  */
 
-app.use = function use(path, fn){
+app.use = function use(path, fn) {
   var mount_app;
+  var mount_path;
 
-  // default path to '/'
-  if (arguments.length < 2) {
-    fn = path;
-    path = '/';
+  // check for .use(path, app) or .use(app) signature
+  if (arguments.length <= 2) {
+    mount_path = typeof path === 'string'
+      ? path
+      : '/';
+    mount_app = typeof path === 'function'
+      ? path
+      : fn;
   }
 
-  // express app
-  if (fn.handle && fn.set) mount_app = fn;
+  // setup router
+  this.lazyrouter();
+  var router = this._router;
 
-  // restore .app property on req and res
-  if (mount_app) {
-    debug('.use app under %s', path);
+  // express app
+  if (mount_app && mount_app.handle && mount_app.set) {
+    debug('.use app under %s', mount_path);
     mount_app.mountpath = path;
-    fn = function(req, res, next) {
+    mount_app.parent = this;
+
+    // restore .app property on req and res
+    router.use(mount_path, function mounted_app(req, res, next) {
       var orig = req.app;
       mount_app.handle(req, res, function(err) {
         req.__proto__ = orig.request;
         res.__proto__ = orig.response;
         next(err);
       });
-    };
-  }
+    });
 
-  this.lazyrouter();
-  this._router.use(path, fn);
-
-  // mounted an app
-  if (mount_app) {
-    mount_app.parent = this;
+    // mounted an app
     mount_app.emit('mount', this);
+
+    return this;
   }
 
+  // pass-through use
+  router.use.apply(router, arguments);
+
   return this;
 };
 

lib/router/index.js

@@ -9,6 +9,8 @@ var mixin = require('utils-merge');
 var debug = require('debug')('express:router');
 var parseUrl = require('parseurl');
 var slice = Array.prototype.slice;
+var toString = Object.prototype.toString;
+var utils = require('../utils');
 
 /**
  * Initialize a new `Router` with the given `options`.
@@ -394,37 +396,47 @@ proto.process_params = function(layer, called, req, res, done) {
  * handlers can operate without any code changes regardless of the "prefix"
  * pathname.
  *
- * @param {String|Function} route
- * @param {Function} fn
- * @return {app} for chaining
  * @api public
  */
 
-proto.use = function(path, fn){
+proto.use = function use(fn) {
+  var offset = 0;
+  var path = '/';
+  var self = this;
+
   // default path to '/'
-  if (arguments.length < 2) {
-    fn = path;
-    path = '/';
-  }
-
   if (typeof fn !== 'function') {
-    var type = {}.toString.call(fn);
-    var msg = 'Router.use() requires callback functions but got a ' + type;
-    throw new Error(msg);
+    offset = 1;
+    path = fn;
   }
 
-  var layer = new Layer(path, {
-    sensitive: this.caseSensitive,
-    strict: false,
-    end: false
-  }, fn);
+  var callbacks = utils.flatten(slice.call(arguments, offset));
 
-  layer.route = undefined;
+  if (callbacks.length === 0) {
+    throw new TypeError('Router.use() requires callback function');
+  }
 
-  // add the middleware
-  debug('use %s %s', path || '/', fn.name || 'anonymous');
+  callbacks.forEach(function (fn) {
+    if (typeof fn !== 'function') {
+      var type = toString.call(fn);
+      var msg = 'Router.use() requires callback function but got a ' + type;
+      throw new TypeError(msg);
+    }
+
+    // add the middleware
+    debug('use %s %s', path, fn.name || '<anonymous>');
+
+    var layer = new Layer(path, {
+      sensitive: self.caseSensitive,
+      strict: false,
+      end: false
+    }, fn);
+
+    layer.route = undefined;
+
+    self.stack.push(layer);
+  });
 
-  this.stack.push(layer);
   return this;
 };
 

test/app.use.js

@@ -16,9 +16,9 @@ describe('app', function(){
     app.use(blog);
   })
 
-  it('should reject numbers', function(){
+  it('should reject missing functions', function(){
     var app = express();
-    app.use.bind(app, 3).should.throw(/Number/);
+    app.use.bind(app, 3).should.throw(/requires callback function/);
   })
 
   describe('.use(app)', function(){
@@ -87,6 +87,32 @@ describe('app', function(){
   })
 
   describe('.use(middleware)', function(){
+    it('should accept multiple arguments', function (done) {
+      var app = express();
+
+      function fn1(req, res, next) {
+        res.setHeader('x-fn-1', 'hit');
+        next();
+      }
+
+      function fn2(req, res, next) {
+        res.setHeader('x-fn-2', 'hit');
+        next();
+      }
+
+      app.use(fn1, fn2, function fn3(req, res) {
+        res.setHeader('x-fn-3', 'hit');
+        res.end();
+      });
+
+      request(app)
+      .get('/')
+      .expect('x-fn-1', 'hit')
+      .expect('x-fn-2', 'hit')
+      .expect('x-fn-3', 'hit')
+      .expect(200, done);
+    })
+
     it('should invoke middleware for all requests', function (done) {
       var app = express();
       var cb = after(3, done);
@@ -122,6 +148,32 @@ describe('app', function(){
       .expect(200, 'saw GET /bar', done);
     })
 
+    it('should accept multiple arguments', function (done) {
+      var app = express();
+
+      function fn1(req, res, next) {
+        res.setHeader('x-fn-1', 'hit');
+        next();
+      }
+
+      function fn2(req, res, next) {
+        res.setHeader('x-fn-2', 'hit');
+        next();
+      }
+
+      app.use('/foo', fn1, fn2, function fn3(req, res) {
+        res.setHeader('x-fn-3', 'hit');
+        res.end();
+      });
+
+      request(app)
+      .get('/foo')
+      .expect('x-fn-1', 'hit')
+      .expect('x-fn-2', 'hit')
+      .expect('x-fn-3', 'hit')
+      .expect(200, done);
+    })
+
     it('should invoke middleware for all requests starting with path', function (done) {
       var app = express();
       var cb = after(3, done);