From d9cb0de2264379c1b6e9386ff7d12be196448050 Mon Sep 17 00:00:00 2001
From: Sumit Mayani <sumi.mayani@gmail.com>
Date: Tue, 21 Apr 2026 11:19:34 +0530
Subject: [PATCH] fix: handle undefined remoteAddress when socket is
 disconnected

getSocketAddr returned undefined when req.socket existed but remoteAddress
was undefined (disconnected socket). Also hardened the fallback to safely
handle missing req.connection. forwarded() now omits the socket address
from the result array rather than including undefined.

Closes #12

Assisted-by AI: Claude (Anthropic)
---
 index.js     |  7 +++----
 test/test.js | 12 ++++++++++++
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/index.js b/index.js
index b2b6bdd..f3d2d30 100644
--- a/index.js
+++ b/index.js
@@ -29,7 +29,7 @@ function forwarded (req) {
   // simple header parsing
   var proxyAddrs = parse(req.headers['x-forwarded-for'] || '')
   var socketAddr = getSocketAddr(req)
-  var addrs = [socketAddr].concat(proxyAddrs)
+  var addrs = (socketAddr ? [socketAddr] : []).concat(proxyAddrs)
 
   // return all addresses
   return addrs
@@ -44,9 +44,8 @@ function forwarded (req) {
  */
 
 function getSocketAddr (req) {
-  return req.socket
-    ? req.socket.remoteAddress
-    : req.connection.remoteAddress
+  var socket = req.socket || req.connection
+  return socket ? socket.remoteAddress : undefined
 }
 
 /**
diff --git a/test/test.js b/test/test.js
index 08e4964..47bf6d4 100644
--- a/test/test.js
+++ b/test/test.js
@@ -58,6 +58,18 @@ describe('forwarded(req)', function () {
       var req = createReq('connection', '10.0.0.1')
       assert.strictEqual(forwarded(req)[0], '10.0.0.1')
     })
+
+    it('should omit socket address when socket is disconnected', function () {
+      var req = { headers: {}, socket: { remoteAddress: undefined } }
+      var addrs = forwarded(req)
+      assert.strictEqual(addrs.indexOf(undefined), -1)
+    })
+
+    it('should omit socket address when both socket and connection are absent', function () {
+      var req = { headers: {} }
+      var addrs = forwarded(req)
+      assert.strictEqual(addrs.indexOf(undefined), -1)
+    })
   })
 })