Support periodic auth checks in SecurityContext on web socket connections

src/support/bus/WebSocketBus.ts

@@ -17,6 +17,8 @@ import {WebSocketCloseEvent} from '../../http/lifecycle/WebSocketCloseEvent'
 import {apiEvent, error} from '../../http/response/api'
 import {AsyncResource, executionAsyncId} from 'async_hooks'
 import {Session} from '../../http/session/Session'
+import {Config} from '../../service/Config'
+import {WebSocketHealthCheckEvent} from '../../http/lifecycle/WebSocketHealthCheckEvent'
 
 @Injectable()
 export class WebSocketBus implements EventBus, AwareOfContainerLifecycle {
@@ -50,6 +52,9 @@ export class WebSocketBus implements EventBus, AwareOfContainerLifecycle {
     @Inject()
     protected readonly session!: Session
 
+    @Inject()
+    protected readonly config!: Config
+
     public readonly uuid = uuid4()
 
     private connected = false
@@ -125,7 +130,7 @@ export class WebSocketBus implements EventBus, AwareOfContainerLifecycle {
         }
     }
 
-    up(): void {
+    async up(): Promise<void> {
         const resource = new AsyncResource('WebSocketBus', {
             triggerAsyncId: executionAsyncId(),
             requireManualDestroy: false,
@@ -147,10 +152,53 @@ export class WebSocketBus implements EventBus, AwareOfContainerLifecycle {
             })
         })
 
+        this.ws.on('close', () => this.bus.push(new WebSocketCloseEvent()))
+        this.ws.on('error', () => this.bus.push(new WebSocketCloseEvent()))
+
+        await this.registerHealthCheck()
+
         this.connected = true
     }
 
+    /**
+     * Set up an interval that fires a `WebSocketHealthCheckEvent` on the request bus.
+     * This can be used, e.g., to check if the user is still logged in.
+     * You can control the interval by setting the `server.socket.healthCheckIntervalSeconds`
+     * config option. Set the option to 0 to disable the interval.
+     * @protected
+     */
+    protected async registerHealthCheck(): Promise<void> {
+        const interval = this.config.safe('server.socket.healthCheckIntervalSeconds')
+            .or(60)
+            .integer()
+
+        if ( interval === 0 ) {
+            return
+        }
+
+        const handle = setInterval(() => {
+            if ( !this.isConnected() ) {
+                return
+            }
+
+            return this.bus.push(new WebSocketHealthCheckEvent())
+        }, interval * 1000)
+
+        await this.bus.subscribe(WebSocketCloseEvent, () => {
+            clearInterval(handle)
+        })
+    }
+
     down(): void {
+        if ( this.connected ) {
+            try {
+                this.ws.close()
+            } catch (e) {
+                this.logging.error('Error closing socket:')
+                this.logging.error(e)
+            }
+        }
+
         this.connected = false
     }