From 0a7b1718c2e66e5f53e3e728910badf535ef82dd Mon Sep 17 00:00:00 2001
From: Paul Kulchenko <paul@kulchenko.com>
Date: Sun, 14 May 2023 00:13:07 -0700
Subject: [PATCH] Update redbean Fetch to close connection upon server request

---
 tool/net/fetch.inc | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/tool/net/fetch.inc b/tool/net/fetch.inc
index 215d1a9aa..a018c5d8f 100644
--- a/tool/net/fetch.inc
+++ b/tool/net/fetch.inc
@@ -227,7 +227,7 @@ static int LuaFetch(lua_State *L) {
   requestlen = appendz(request).i;
   _gc(request);
 
-  if (keepalive != kaKEEP && keepalive != kaCLOSE) {
+  if (keepalive == kaNONE || keepalive == kaOPEN) {
     /*
      * Perform DNS lookup.
      */
@@ -449,6 +449,15 @@ Finished:
            msg.status, urlarg, FetchHeaderLength(kHttpServer),
            FetchHeaderData(kHttpServer));
 
+  // check if the server has requested to close the connection
+  // https://www.rfc-editor.org/rfc/rfc2616#section-14.10
+  if (keepalive && keepalive != kaCLOSE
+                && FetchHasHeader(kHttpConnection)
+                && FetchHeaderEqualCase(kHttpConnection, "close")) {
+    VERBOSEF("(ftch) close keepalive on server request");
+    keepalive = kaCLOSE;
+  }
+
   // need to save updated sock for keepalive
   if (keepalive && keepalive != kaCLOSE && lua_istable(L, 2)) {
     lua_getfield(L, 2, "keepalive");