From f1e3d07b2bfa7f5782b9634e95ba1a4d36ce349a Mon Sep 17 00:00:00 2001
From: achingbrain <alex@achingbrain.net>
Date: Wed, 24 Jul 2024 15:33:44 +0200
Subject: [PATCH] fix: handle null server address

The types for the `Server.address()` method in `@types/ws` are
missing a return type of `null`.  This can happen when a incoming
connection is recieved after the ws `Server` has been closed but
before the underlying HTTP server has finished closing down.

https://github.com/DefinitelyTyped/DefinitelyTyped/pull/70132 will
address the type problem, the change here is to handle the `null`
return value.

It also calls `.destroy` on the incoming message since we'd want
to reclaim the resources immediately and not wait for the remote
to time out.
---
 src/server.ts | 24 +++++++++++++++++-------
 1 file changed, 17 insertions(+), 7 deletions(-)

diff --git a/src/server.ts b/src/server.ts
index 8f4fde3..32c4e32 100644
--- a/src/server.ts
+++ b/src/server.ts
@@ -61,15 +61,25 @@ class Server extends EventEmitter {
   }
 
   onWsServerConnection (socket: WebSocket, req: http.IncomingMessage): void {
-    const addr = this.wsServer.address()
+    let addr: string | AddressInfo
 
-    if (typeof addr === 'string') {
-      this.emit('error', new Error('Cannot listen on unix sockets'))
-      return
-    }
+    try {
+      if (req.socket.remoteAddress == null || req.socket.remotePort == null) {
+        throw new Error('Remote connection did not have address and/or port')
+      }
+
+      addr = this.wsServer.address()
+
+      if (typeof addr === 'string') {
+        throw new Error('Cannot listen on unix sockets')
+      }
 
-    if (req.socket.remoteAddress == null || req.socket.remotePort == null) {
-      this.emit('error', new Error('Remote connection did not have address and/or port'))
+      if (addr == null) {
+        throw new Error('Server was closing or not running')
+      }
+    } catch (err: any) {
+      req.destroy(err)
+      this.emit('error', err)
       return
     }