Revert keepalive default

lightbug_http/server.mojo

@@ -477,7 +477,7 @@ struct Server(Movable):
     fn __init__(
         out self,
         var address: String = "127.0.0.1",
-        tcp_keep_alive: Bool = True,
+        tcp_keep_alive: Bool = False,
     ):
         self.config = ServerConfig()
         self._address = address^
@@ -487,7 +487,7 @@ struct Server(Movable):
         out self,
         var config: ServerConfig,
         var address: String = "127.0.0.1",
-        tcp_keep_alive: Bool = True,
+        tcp_keep_alive: Bool = False,
     ):
         self.config = config^
         self._address = address^

tests/integration/integration_client.py

@@ -1,3 +1,4 @@
+import concurrent.futures
 import requests
 import socket
 import time
@@ -32,6 +33,24 @@
 )
 assert response.status_code == 200
 
+print("\n~~~ Testing parallel connections ~~~")
+# Browsers open 6+ parallel connections for assets.
+# A single-threaded server with keep-alive blocks on conn.read() waiting for
+# the next request, preventing other connections from being accepted.
+# This test verifies all parallel requests complete within a reasonable time.
+
+
+def fetch(path):
+    return requests.get(f"http://127.0.0.1:8080{path}", headers={"connection": "close"})
+
+
+with concurrent.futures.ThreadPoolExecutor(max_workers=4) as executor:
+    futures = [executor.submit(fetch, f"/?n={i}") for i in range(4)]
+    results = concurrent.futures.wait(futures, timeout=5)
+    assert len(results.done) == 4, f"Only {len(results.done)}/4 parallel requests completed within 5s"
+    for f in results.done:
+        assert f.result().status_code == 200
+
 print("\n~~~ Testing content-length mismatch (smaller) ~~~")
 
 

tests/integration/integration_test_server.mojo

@@ -37,6 +37,6 @@ struct IntegrationTestService(HTTPService):
 
 
 fn main() raises:
-    var server = Server(tcp_keep_alive=True)
+    var server = Server()
     var service = IntegrationTestService()
     server.listen_and_serve("127.0.0.1:8080", service)

tests/lightbug_http/test_server.mojo

@@ -0,0 +1,14 @@
+import testing
+from lightbug_http.server import Server
+
+
+def test_server_defaults_to_keep_alive_off():
+    var server = Server()
+    testing.assert_false(
+        server.tcp_keep_alive,
+        "tcp_keep_alive must default to False for single-threaded server",
+    )
+
+
+def main():
+    testing.TestSuite.discover_tests[__functions_in_module()]().run()