Merge pull request #2168 from hwasurr/master

docs(websockets): fix invalid links

Author: kamilmysliwiec

content/websockets/gateways.md

@@ -21,7 +21,7 @@ $ npm i --save @nestjs/websockets @nestjs/platform-socket.io
 
 #### Overview
 
-In general, each gateway is listening on the same port as the **HTTP server**, unless your app is not a web application, or you have changed the port manually. This default behavior can be modified by passing an argument to the `@WebSocketGateway(80)` decorator where `80` is a chosen port number. You can also set a [namespace](https://socket.io/docs/rooms-and-namespaces/) used by the gateway using the following construction:
+In general, each gateway is listening on the same port as the **HTTP server**, unless your app is not a web application, or you have changed the port manually. This default behavior can be modified by passing an argument to the `@WebSocketGateway(80)` decorator where `80` is a chosen port number. You can also set a [namespace](https://socket.io/docs/v4/namespaces/) used by the gateway using the following construction:
 
 ```typescript
 @WebSocketGateway(80, { namespace: 'events' })
@@ -99,7 +99,7 @@ handleEvent(client, data) {
 }
 ```
 
-In the example above, the `handleEvent()` function takes two arguments. The first one is a platform-specific [socket instance](https://socket.io/docs/server-api/#socket), while the second one is the data received from the client. This approach is not recommended though, because it requires mocking the `socket` instance in each unit test.
+In the example above, the `handleEvent()` function takes two arguments. The first one is a platform-specific [socket instance](https://socket.io/docs/v4/server-api/#socket), while the second one is the data received from the client. This approach is not recommended though, because it requires mocking the `socket` instance in each unit test.
 
 Once the `events` message is received, the handler sends an acknowledgment with the same data that was sent over the network. In addition, it's possible to emit messages using a library-specific approach, for example, by making use of `client.emit()` method. In order to access a connected socket instance, use `@ConnectedSocket()` decorator.