request.active(). Closes hapijs#3827

Author: hueniverse

API.md

@@ -1,4 +1,4 @@
-# v17.5.x API Reference
+# v17.6.x API Reference
 
 <!-- toc -->
 
@@ -238,6 +238,7 @@
     - [`request.server`](#request.server)
     - [`request.state`](#request.state)
     - [`request.url`](#request.url)
+  - [`request.active()`](#request.active())
   - [`request.generateResponse(source, [options])`](#request.generateResponse())
   - [`request.log(tags, [data])`](#request.log())
   - [`request.route.auth.access(request)`](#request.route.auth.access())
@@ -4795,6 +4796,36 @@ Returns a [`response`](#response-object) which you can pass into the [reply inte
         - `response` - the response object being marshaled.
         - should not throw errors (which are logged but otherwise ignored).
 
+### <a name="request.active()" /> `request.active()`
+
+Returns `true` when the request is active and processing should continue and `false` when the
+request terminated early or completed its lifecycle. Useful when request processing is a
+resource-intensive operation and should be terminated early if the request is no longer active
+(e.g. client disconnected or aborted early).
+
+```js
+const Hapi = require('hapi');
+const server = Hapi.server({ port: 80 });
+
+server.route({
+    method: 'POST',
+    path: '/worker',
+    handler: function (request, h) {
+
+        // Do some work...
+
+        // Check if request is still active
+        if (!request.active()) {
+            return h.close;
+        }
+
+        // Do some more work...
+
+        return null;
+    }
+});
+```
+
 ### <a name="request.log()" /> `request.log(tags, [data])`
 
 Logs request-specific events. When called, the server emits a [`'request'` event](#server.events.request)

README.md

@@ -10,7 +10,7 @@ developers to focus on writing reusable application logic in a highly modular an
 
 Version 17.x only supports node v8.9.0 and over. For older version of node please use version 16.x.
 
-Development version: **17.5.x** ([release notes](https://github.com/hapijs/hapi/issues?labels=release+notes&page=1&state=closed)) 
+Development version: **17.6.x** ([release notes](https://github.com/hapijs/hapi/issues?labels=release+notes&page=1&state=closed)) 
 [![Linux Build Status](https://secure.travis-ci.org/hapijs/hapi.svg?branch=master)](https://travis-ci.org/hapijs/hapi)
 [![Windows Build Status](https://ci.appveyor.com/api/projects/status/github/hapijs/hapi?branch=master&svg=true)](https://ci.appveyor.com/project/hueniverse/hapi)
 

lib/request.js

@@ -148,6 +148,11 @@ exports = module.exports = internals.Request = class {
         this.method = method.toLowerCase();
     }
 
+    active() {
+
+        return !!this._eventContext.request;
+    }
+
     async _execute() {
 
         this.info.acceptEncoding = this._core.compression.accept(this);
@@ -329,7 +334,9 @@ exports = module.exports = internals.Request = class {
 
         await this._postCycle();
 
-        if (typeof this.response === 'symbol') {                        // close or abandon
+        if (!this._eventContext.request ||
+            typeof this.response === 'symbol') {                        // close or abandon
+
             this._abort();
             return;
         }

npm-shrinkwrap.json

@@ -211,6 +211,49 @@ describe('Request', () => {
         expect(res3.result).to.match(/10$/);
     });
 
+    describe('active()', () => {
+
+        it('exits handler early when request is no longer active', async () => {
+
+            const server = Hapi.server();
+            const team = new Teamwork();
+
+            let rounds = 0;
+            server.route({
+                method: 'GET',
+                path: '/',
+                options: {
+                    handler: async (request, h) => {
+
+                        for (let i = 0; i < 10; ++i) {
+                            ++rounds;
+                            await Hoek.wait(10);
+
+                            if (!request.active()) {
+                                break;
+                            }
+                        }
+
+                        team.attend();
+                        return null;
+                    }
+                }
+            });
+
+            await server.start();
+
+            const req = Http.get(server.info.uri, (res) => { });
+            req.on('error', Hoek.ignore);
+
+            await Hoek.wait(50);
+            req.abort();
+            await server.stop();
+
+            await team.work;
+            expect(rounds).to.equal(5);
+        });
+    });
+
     describe('_execute()', () => {
 
         it('returns 400 on invalid path', async () => {