alexa: fix race condition in sendResponse

koush · Nov 23, 2023 · b04aa75 · b04aa75
1 parent fc7d1ea
commit b04aa75
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Showing 4 changed files with 69 additions and 32 deletions.
diff --git a/plugins/alexa/package-lock.json b/plugins/alexa/package-lock.json
diff --git a/plugins/alexa/package.json b/plugins/alexa/package.json
@@ -1,6 +1,6 @@
 {
    "name": "@scrypted/alexa",
-   "version": "0.2.8",
+   "version": "0.2.9",
    "scripts": {
       "scrypted-setup-project": "scrypted-setup-project",
       "prescrypted-setup-project": "scrypted-package-json",
@@ -39,6 +39,7 @@
    },
    "devDependencies": {
       "@types/node": "^18.4.2",
-      "@scrypted/sdk": "../../sdk"
+      "@scrypted/sdk": "../../sdk",
+      "@scrypted/common": "../../common"
    }
 }
diff --git a/plugins/alexa/src/main.ts b/plugins/alexa/src/main.ts
@@ -632,8 +632,10 @@ class AlexaPlugin extends ScryptedDeviceBase implements HttpRequestHandler, Mixi
         debug("received directive from alexa", mapName, body);
 
         const handler = alexaHandlers.get(mapName);
-        if (handler)
-            return handler.apply(this, [request, response, directive]);
+        if (handler) {
+            await handler.apply(this, [request, response, directive]);
+            return;
+        }
 
         const deviceHandler = alexaDeviceHandlers.get(mapName);
 
@@ -644,7 +646,8 @@ class AlexaPlugin extends ScryptedDeviceBase implements HttpRequestHandler, Mixi
                 return;
             }
 
-            return deviceHandler.apply(this, [request, response, directive, device]);
+            await deviceHandler.apply(this, [request, response, directive, device]);
+            return;
         } else {
             this.console.error(`no handler for: ${mapName}`);
         }

diff --git a/plugins/alexa/src/types/camera/handlers.ts b/plugins/alexa/src/types/camera/handlers.ts
@@ -4,6 +4,7 @@ import { v4 as createMessageId } from 'uuid';
 import { AlexaHttpResponse, sendDeviceResponse } from "../../common";
 import { alexaDeviceHandlers } from "../../handlers";
 import { Response, WebRTCAnswerGeneratedForSessionEvent, WebRTCSessionConnectedEvent, WebRTCSessionDisconnectedEvent } from '../../alexa'
+import { Deferred } from '@scrypted/common/src/deferred';
 
 export class AlexaSignalingSession implements RTCSignalingSession {
     constructor(public response: AlexaHttpResponse, public directive: any) {
@@ -13,7 +14,8 @@ export class AlexaSignalingSession implements RTCSignalingSession {
 
     __proxy_props: { options: RTCSignalingOptions; };
     options: RTCSignalingOptions;
-
+    remoteDescription = new Deferred<void>();
+
     async getOptions(): Promise<RTCSignalingOptions> {
         return this.options;
     }
@@ -39,11 +41,17 @@ export class AlexaSignalingSession implements RTCSignalingSession {
     }
 
     async createLocalDescription(type: "offer" | "answer", setup: RTCAVSignalingSetup, sendIceCandidate: RTCSignalingSendIceCandidate): Promise<RTCSessionDescriptionInit> {
-        if (type !== 'offer')
-            throw new Error('Alexa only supports RTC offer');
+        if (type !== 'offer') {
+            const e = new Error('Alexa only supports RTC offer');
+            this.remoteDescription.reject(e);
+            throw e;
+        }
 
-        if (sendIceCandidate)
-            throw new Error("Alexa does not support trickle ICE");
+        if (sendIceCandidate) {
+            const e = new Error("Alexa does not support trickle ICE");
+            this.remoteDescription.reject(e);
+            throw e;
+        }
 
         return {
             type: type,
@@ -67,15 +75,16 @@ export class AlexaSignalingSession implements RTCSignalingSession {
             },
             context: undefined
         };
-    
+
         data.event.header.name = "AnswerGeneratedForSession";
         data.event.header.messageId = createMessageId();
-    
+
         data.event.payload.answer = {
             format: 'SDP',
             value: description.sdp,
         };
 
+        this.remoteDescription.resolve();
         this.response.send(data);
     }
 }
@@ -85,13 +94,14 @@ const sessionCache = new Map<string, RTCSessionControl>();
 alexaDeviceHandlers.set('Alexa.RTCSessionController/InitiateSessionWithOffer', async (request, response, directive: any, device: ScryptedDevice & RTCSignalingChannel) => {
     const { header, endpoint, payload } = directive;
     const { sessionId } = payload;
-    
+
     const session = new AlexaSignalingSession(response, directive);
     const control = await device.startRTCSignalingSession(session);
     control.setPlayback({
         audio: true,
         video: false,
-    })
+    });
+    await session.remoteDescription.promise;
 
     sessionCache.set(sessionId, control);
 });
@@ -115,13 +125,13 @@ alexaDeviceHandlers.set('Alexa.RTCSessionController/SessionConnected', async (re
 alexaDeviceHandlers.set('Alexa.RTCSessionController/SessionDisconnected', async (request, response, directive: any, device: ScryptedDevice) => {
     const { header, endpoint, payload } = directive;
     const { sessionId } = payload;
-    
+
     const session = sessionCache.get(sessionId);
     if (session) {
         sessionCache.delete(sessionId);
         await session.endSession();
     }
-    
+
     const data: WebRTCSessionDisconnectedEvent = {
         "event": {
             header,
@@ -130,9 +140,9 @@ alexaDeviceHandlers.set('Alexa.RTCSessionController/SessionDisconnected', async
         },
         context: undefined
     };
-    
+
     data.event.header.messageId = createMessageId();
-    
+
     response.send(data);
 });
 
@@ -152,14 +162,14 @@ alexaDeviceHandlers.set('Alexa.SmartVision.ObjectDetectionSensor/SetObjectDetect
         },
         "context": {
             "properties": [{
-                    "namespace": "Alexa.SmartVision.ObjectDetectionSensor",
-                    "name": "objectDetectionClasses",
-                    "value": detectionTypes.classes.map(type => ({
-                        "imageNetClass": type
-                    })),
-                    timeOfSample: new Date().toISOString(),
-                    uncertaintyInMilliseconds: 0
-                }]
+                "namespace": "Alexa.SmartVision.ObjectDetectionSensor",
+                "name": "objectDetectionClasses",
+                "value": detectionTypes.classes.map(type => ({
+                    "imageNetClass": type
+                })),
+                timeOfSample: new Date().toISOString(),
+                uncertaintyInMilliseconds: 0
+            }]
         }
     };