Support handlers calling res.destroy() to abort sending a response

Author: kanongil

API.md

@@ -65,11 +65,12 @@ Returns a response object where:
   - `req` - the simulated request object.
   - `res` - the simulated response object.
 - `headers` - an object containing the response headers.
-- `statusCode` - the HTTP status code.
+- `statusCode` - the HTTP status code. If response is aborted before headers are sent, the code is `499`.
 - `statusMessage` - the HTTP status message.
 - `payload` - the payload as a UTF-8 encoded string.
 - `rawPayload` - the raw payload as a Buffer.
 - `trailers` - an object containing the response trailers.
+- `aborted` - optional property which is `true` for aborted, ie. not fully transmitted, responses.
 
 ### `Shot.isInjection(obj)`
 

lib/index.d.ts

@@ -47,7 +47,7 @@ export interface ResponseObject {
     headers: OutgoingHttpHeaders;
 
     /**
-     * The HTTP status code.
+     * The HTTP status code. If response is aborted before headers are sent, the code is `499`.
      */
     statusCode: number;
 
@@ -70,6 +70,11 @@ export interface ResponseObject {
      * An object containing the response trailers
      */
     trailers: NodeJS.Dict<string>;
+
+    /**
+     * A boolean which is `true` for aborted, ie. not fully transmitted, responses.
+     */
+    aborted?: true;
 }
 
 type PartialURL = Pick<UrlObject, 'protocol' | 'hostname' | 'port' | 'query'> & { pathname: string };

lib/response.js

@@ -3,6 +3,8 @@
 const Http = require('http');
 const Stream = require('stream');
 
+const Hoek = require('@hapi/hoek');
+
 const Symbols = require('./symbols');
 
 
@@ -17,21 +19,39 @@ exports = module.exports = internals.Response = class extends Http.ServerRespons
         this._shot = { headers: null, trailers: {}, payloadChunks: [] };
         this.assignSocket(internals.nullSocket());
 
+        this.socket.on('error', Hoek.ignore);        // The socket can be destroyed with an error
+
         if (req._shot.simulate.close) {
             // Ensure premature, manual close is forwarded to res.
             // In HttpServer the socket closing actually triggers close on both req and res.
             req.once('close', () => {
 
-                process.nextTick(() => this.emit('close'));
+                process.nextTick(() => this.destroy());
             });
         }
 
-        this.once('finish', () => {
+        const finalize = (aborted) => {
 
             const res = internals.payload(this);
             res.raw.req = req;
+            if (aborted) {
+                res.aborted = aborted;
+                if (!this.headersSent) {
+                    res.statusCode = 499;
+                }
+            }
+
+            this.removeListener('close', abort);
+
             process.nextTick(() => onEnd(res));
-        });
+        };
+        const abort = finalize.bind(this, true);
+
+        this.once('finish', finalize);
+
+        // Add fallback listener that will not be called if 'finish' is emitted first
+
+        this.on('close', abort);
     }
 
     writeHead(...args) {

test/index.js

@@ -537,6 +537,96 @@ describe('inject()', () => {
         });
         expect(res.payload.toString()).to.equal(body.toString());
     });
+
+    it('returns aborted on immediate res.destroy()', async () => {
+
+        const dispatch = function (req, res) {
+
+            res.destroy();
+        };
+
+        const res = await Shot.inject(dispatch, { method: 'get', url: '/' });
+        expect(res.aborted).to.be.true();
+        expect(res.statusCode).to.equal(499);
+        expect(res.raw.res.errored).to.not.exist();
+    });
+
+    it('returns aborted on immediate res.destroy(error)', async () => {
+
+        const dispatch = function (req, res) {
+
+            res.destroy(new Error('stop'));
+        };
+
+        const res = await Shot.inject(dispatch, { method: 'get', url: '/' });
+        expect(res.aborted).to.be.true();
+        expect(res.statusCode).to.equal(499);
+        expect(res.raw.res.errored).to.be.an.error('stop');
+    });
+
+    it('returns aborted on res.destroy() while transmitting payload', async () => {
+
+        const dispatch = function (req, res) {
+
+            res.writeHead(404);
+            res.write('data');
+            setTimeout(() => res.destroy(), 1);
+        };
+
+        const res = await Shot.inject(dispatch, { method: 'get', url: '/' });
+        expect(res.aborted).to.be.true();
+        expect(res.statusCode).to.equal(404);
+        expect(res.raw.res.errored).to.not.exist();
+        expect(res.payload).to.equal('data');
+    });
+
+    it('returns aborted on res.destroy(error) while transmitting payload', async () => {
+
+        const dispatch = function (req, res) {
+
+            res.writeHead(404);
+            res.write('data');
+            setTimeout(() => res.destroy(new Error('stop')), 1);
+        };
+
+        const res = await Shot.inject(dispatch, { method: 'get', url: '/' });
+        expect(res.aborted).to.be.true();
+        expect(res.statusCode).to.equal(404);
+        expect(res.raw.res.errored).to.be.an.error('stop');
+        expect(res.payload).to.equal('data');
+    });
+
+    it('handles res.destroy() after transmitting payload', async () => {
+
+        const dispatch = function (req, res) {
+
+            res.writeHead(404);
+            res.end('data');
+            res.destroy();
+        };
+
+        const res = await Shot.inject(dispatch, { method: 'get', url: '/' });
+        expect(res.aborted).to.not.exist();
+        expect(res.statusCode).to.equal(404);
+        expect(res.raw.res.errored).to.not.exist();
+        expect(res.payload).to.equal('data');
+    });
+
+    it('handles res.destroy(error) after transmitting payload', async () => {
+
+        const dispatch = function (req, res) {
+
+            res.writeHead(404);
+            res.end('data');
+            res.destroy(new Error('stop'));
+        };
+
+        const res = await Shot.inject(dispatch, { method: 'get', url: '/' });
+        expect(res.aborted).to.not.exist();
+        expect(res.statusCode).to.equal(404);
+        expect(res.raw.res.errored).to.be.an.error('stop');
+        expect(res.payload).to.equal('data');
+    });
 });
 
 describe('writeHead()', () => {