Roundups

README.md

@@ -64,7 +64,7 @@ WebSocket server options can be provided via `cds.requires.websocket.options`.
 
 Default protocol path is `/ws` and can be overwritten via `cds.env.protocols.websocket.path` resp. `cds.env.protocols.ws.path`;
 
-Services are exposed therefore like this: `/ws/<service-path`:
+Services are exposed therefore like this: `/ws/<service-path>`:
 
 **Examples:**
 
@@ -93,6 +93,14 @@ Locally, the following default environment files need to exist:
 - `test/\_env/default-env.json`
 - `test/\_env/approuter/default-services.json`
 
+Approuter is configured to support websockets in `xs-app.json` according to [@sap/approuter - websockets property](https://www.npmjs.com/package/@sap/approuter#websockets-property):
+
+```
+"websockets": {
+  "enabled": true
+}
+```
+
 #### Local
 
 For local testing a mocked basic authorization is hardcoded in `flp.html/index.html`.
@@ -278,43 +286,63 @@ describe("WebSocket", () => {
 ### Adapters (Socket.IO)
 
 An Adapter is a server-side component which is responsible for broadcasting events to all or a subset of clients.
-Details can be found here: https://socket.io/docs/v4/adapter/
-
-Currently, two adapters are supported out-of-the-box:
 
 #### Redis
 
 Every event that is sent to multiple clients is sent to all matching clients connected to the current server
 and published in a Redis channel, and received by the other Socket.IO servers of the cluster.
 
-##### Redis Adapter
+Redis adapter can be disabled by setting `cds.requires.websocket.adapter: false`.
+
+##### WS
+
+Per default a basic publish/subscribe redis adapter is active, if the app is bound to a Redis service. 
+The Redis channel key can be specified via `cds.requires.websocket.adapter.options.key`. Default value is `websocket`.
+
+##### Socket.IO
 
-To use the redis adapter, the following steps have to be performed:
+The following Redis adapters for Socket.IO are supported out-of-the-box.
+
+###### Redis Adapter
+
+To use the Redis Adapter, the following steps have to be performed:
 
 - Install Redis Adapter dependency:
   `npm install @socket.io/redis-adapter`
-- Set `cds.requires.websocket.adapter: "@socket.io/redis-adapter"`
+- Set `cds.requires.websocket.adapter.impl: "@socket.io/redis-adapter"`
 - Application needs to be bound to a Redis instance
   - Locally a `default-env.json` file need to exist with redis configuration
-- Redis adapter options can be specified via `cds.requires.websocket.adapter.options`;
+- Redis Adapter options can be specified via `cds.requires.websocket.adapter.options`
 
 Details:
 https://socket.io/docs/v4/redis-adapter/
 
-##### Redis Stream Adapter
+###### Redis Streams Adapter
 
-To use the redis adapter, the following steps have to be performed:
+To use the Redis Stream Adapter, the following steps have to be performed:
 
-- Install Redis Adapter dependency:
-  `npm install @socket.io/redis-adapter`
-- Set `cds.requires.websocket.adapter: "@socket.io/redis-streams-adapter"`
+- Install Redis Streams Adapter dependency:
+  `npm install @socket.io/redis-streams-adapter`
+- Set `cds.requires.websocket.adapter.impl: "@socket.io/redis-streams-adapter"`
 - Application needs to be bound to a Redis instance
   - Locally a `default-env.json` file need to exist with redis configuration
-- Redis adapter options can be specified via `cds.requires.websocket.adapter.options`;
+- Redis Streams Adapter options can be specified via `cds.requires.websocket.adapter.options`
 
 Details:
 https://socket.io/docs/v4/redis-streams-adapter/
 
+### Deployment
+
+This module also works on a deployed infrastructure like Cloud Foundry (CF) or Kubernetes (K8s).
+
+An example Cloud Foundry deployment can be found in `test/_env`:
+- `cd test/_env`
+  - [manifest.yml](test/_env/manifest.yml)
+- `npm run cf:push`
+  - Prepares modules `approuter` and `backend` in `test/_env` and pushes to Cloud Foundry
+    - Approuter performs authentication flow with XSUAA and forwards to backend
+    - Backend serves endpoints (websocket, odata) and UI apps (runs on an in-memory SQlite3 database)
+
 ## Support, Feedback, Contributing
 
 This project is open to feature requests/suggestions, bug reports etc. via [GitHub issues](https://github.com/cap-js-community/websocket/issues). Contribution and feedback are encouraged and always welcome. For more information about how to contribute, the project structure, as well as additional contribution information, see our [Contribution Guidelines](CONTRIBUTING.md).

package.json

@@ -27,7 +27,7 @@
     "start:socketio": "npm run start:socketio --prefix=./test/_env",
     "start:uaa": "npm run start:uaa --prefix=./test/_env",
     "start:socketio:uaa": "npm run start:socketio:uaa --prefix=./test/_env",
-    "start:approuter": "npm start --prefix=./test/_env/approuter",
+    "start:approuter": "PORT=5001 npm start --prefix=./test/_env/approuter",
     "test": "jest",
     "test:update": "npm test -- -u",
     "lint": "npm run eslint && npm run prettier",

src/socket/socket.io.js

@@ -65,6 +65,9 @@ class SocketIOServer extends SocketServer {
 
 async function applyAdapter() {
   try {
+    if (cds.env.requires.websocket?.adapter === false) {
+      return;
+    }
     const adapterImpl = cds.env.requires?.websocket?.adapter?.impl;
     if (adapterImpl) {
       const { createAdapter } = require(adapterImpl);

src/socket/ws.js

@@ -39,9 +39,13 @@ class SocketWSServer extends SocketServer {
         LOG?.error(error);
       });
       applyMiddleware(ws, request, async () => {
-        const redisClient = await redis.createMainClientAndConnect();
-        const channel = cds.env.requires.websocket?.adapter?.options?.key ?? "websocket";
-        subscribeRedis(redisClient, ws, channel);
+        const adapterActive = cds.env.requires.websocket?.adapter !== false;
+        const redisChannel = cds.env.requires.websocket?.adapter?.options?.key ?? "websocket";
+        let redisClient;
+        if (adapterActive) {
+          redisClient = await redis.createMainClientAndConnect();
+          subscribeRedis(redisClient, ws, redisChannel);
+        }
         connected &&
           connected({
             socket: ws,
@@ -66,7 +70,9 @@ class SocketWSServer extends SocketServer {
                   // ignore
                 }
                 if (payload?.event === event) {
-                  publishRedis(redisClient, ws, channel, message);
+                  if (adapterActive) {
+                    publishRedis(redisClient, ws, redisChannel, message);
+                  }
                   callback(payload.data);
                 }
               });
@@ -126,20 +132,20 @@ function applyMiddleware(ws, request, next) {
   apply();
 }
 
-function subscribeRedis(redisClient, ws, channel) {
-  if (redisClient) {
-    redisClient.subscribe(channel);
-    redisClient.on("message", (onChannel, message) => {
+function subscribeRedis(client, ws, channel) {
+  if (client) {
+    client.subscribe(channel);
+    client.on("message", (onChannel, message) => {
       if (onChannel === channel) {
         ws.send(message);
       }
     });
   }
 }
 
-function publishRedis(redisClient, ws, channel, message) {
-  if (redisClient) {
-    redisClient.publish(channel, message);
+function publishRedis(client, ws, channel, message) {
+  if (client) {
+    client.publish(channel, message);
   }
 }
 

test/_env/approuter/package.json

@@ -6,7 +6,7 @@
     "@sap/approuter": "^15.0.0"
   },
   "scripts": {
-    "start": "PORT=5001 node node_modules/@sap/approuter/approuter.js"
+    "start": "node node_modules/@sap/approuter/approuter.js"
   },
   "engines": {
     "node": ">=20"

test/_env/approuter/xs-app.json

@@ -8,7 +8,8 @@
     {
       "source": ".*",
       "destination": "srv",
-      "csrfProtection": false
+      "csrfProtection": false,
+      "authenticationType": "xsuaa"
     }
   ]
 }