merge

docs/api/context.md

@@ -102,6 +102,12 @@ throw err;
   error messages since you do not want to leak failure
   details.
 
+### ctx.respond
+
+  To bypass Koa's built-in response handling, you may explicitly set `this.respond = false;`. Use this if you want to write to the raw `res` object instead of letting Koa handle the response for you.
+
+  Note that using this is __not__ supported by Koa. This may break intended functionality of Koa middleware and Koa itself. Using this properly is considered a hack and is only a convenience to those wishing to use traditional `fn(req, res)` functions and middleware within Koa.
+
 ## Request aliases
 
   The following accessors and alias [Request](request.md) equivalents:

lib/application.js

@@ -184,6 +184,8 @@ function *respond(next){
 
   yield *next;
 
+  if (false === this.respond) return;
+
   var res = this.res;
   if (res.headersSent || !res.socket.writable) return;
 

lib/context.js

@@ -115,6 +115,9 @@ var proto = module.exports = {
     // delegate
     this.app.emit('error', err, this);
 
+    // unset all headers
+    this.res._headers = {};
+
     // force text/plain
     this.type = 'text';
 
@@ -128,6 +131,7 @@ var proto = module.exports = {
     var code = http.STATUS_CODES[err.status];
     var msg = err.expose ? err.message : code;
     this.status = err.status;
+    this.length = Buffer.byteLength(msg);
     this.res.end(msg);
   }
 };

package.json

@@ -28,7 +28,7 @@
     "debug": "*",
     "mime": "~1.2.11",
     "fresh": "~0.2.1",
-    "koa-compose": "~2.1.0",
+    "koa-compose": "~2.2.0",
     "cookies": "~0.3.7",
     "keygrip": "~1.0.0",
     "delegates": "0.0.3"

test/application.js

@@ -94,6 +94,31 @@ describe('app.use(fn)', function(){
 })
 
 describe('app.respond', function(){
+  describe('when this.respond === false', function(){
+    it('should bypass app.respond', function(done){
+      var app = koa();
+
+      app.use(function *(){
+        this.body = 'Hello';
+        this.respond = false;
+
+        var res = this.res;
+        setImmediate(function () {
+          res.setHeader('Content-Type', 'text/plain');
+          res.end('lol');
+        })
+      })
+
+      var server = app.listen();
+
+      request(server)
+      .get('/')
+      .expect(200)
+      .expect('lol')
+      .end(done);
+    })
+  })
+
   describe('when HEAD is used', function(){
     it('should not respond with the body', function(done){
       var app = koa();

test/context/onerror.js

@@ -0,0 +1,53 @@
+
+var koa = require('../..');
+var request = require('supertest');
+
+describe('ctx.onerror(err)', function(){
+  it('should respond', function(done){
+    var app = koa();
+
+    app.use(function *(next){
+      this.body = 'something else';
+
+      this.throw(499, 'boom');
+    })
+
+    var server = app.listen();
+
+    request(server)
+    .get('/')
+    .expect(499)
+    .expect('Content-Type', 'text/plain; charset=utf-8')
+    .expect('Content-Length', '4')
+    .end(done);
+  })
+
+  it('should unset all headers', function(done){
+    var app = koa();
+
+    app.use(function *(next){
+      this.set('Vary', 'Accept-Encoding');
+      this.set('X-CSRF-Token', 'asdf');
+      this.body = 'response';
+
+      this.throw(499, 'boom');
+    })
+
+    var server = app.listen();
+
+    request(server)
+    .get('/')
+    .expect(499)
+    .expect('Content-Type', 'text/plain; charset=utf-8')
+    .expect('Content-Length', '4')
+    .end(function(err, res){
+      if (err) return done(err);
+
+      res.headers.should.not.have.property('vary');
+      res.headers.should.not.have.property('x-csrf-token');
+      res.headers.should.not.have.property('x-powered-by');
+
+      done();
+    })
+  })
+})