feat: improve types by extending socket.io module (#6)

README.md

@@ -44,13 +44,17 @@ io.use(
   })
 )
 
-io.on('connection', async () => {
+io.on('connection', async (socket) => {
+  // jwt payload of the connected client
+  console.log(socket.decodedToken)
   const clients = await io.sockets.allSockets()
+  if (clients != null) {
     for (const clientId of clients) {
       const client = io.sockets.sockets.get(clientId)
-    client.emit('messages', { message: 'Success!' })
+      client?.emit('messages', { message: 'Success!' })
       // we can access the jwt payload of each connected client
-    console.log(client.decodedToken)
+      console.log(client?.decodedToken)
+    }
   }
 })
 ```

src/authorize.ts

@@ -3,10 +3,19 @@ import { Socket } from 'socket.io'
 
 import { UnauthorizedError } from './UnauthorizedError'
 
+declare module 'socket.io' {
+  interface Socket extends ExtendedSocket {}
+}
+
 interface ExtendedError extends Error {
   data?: any
 }
 
+interface ExtendedSocket {
+  encodedToken?: string
+  decodedToken?: any
+}
+
 type SocketIOMiddleware = (
   socket: Socket,
   next: (err?: ExtendedError) => void
@@ -41,7 +50,7 @@ export const authorize = (options: AuthorizeOptions): SocketIOMiddleware => {
       )
     }
     // Store encoded JWT
-    socket = Object.assign(socket, { encodedToken: token })
+    socket.encodedToken = token
     let payload: any
     try {
       payload = jwt.verify(token, secret, { algorithms })
@@ -53,7 +62,7 @@ export const authorize = (options: AuthorizeOptions): SocketIOMiddleware => {
       )
     }
     // Store decoded JWT
-    socket = Object.assign(socket, { decodedToken: payload })
+    socket.decodedToken = payload
     return next()
   }
 }