Add test for pipeline request parsing bug

CMakeLists.txt

@@ -207,6 +207,12 @@ add_executable(test_metric tests/test_metric.cpp)
 target_link_libraries(test_metric doctest_impl weaseldb_sources_debug)
 target_compile_options(test_metric PRIVATE -UNDEBUG)
 
+# HTTP handler test
+add_executable(test_http_handler tests/test_http_handler.cpp)
+target_link_libraries(test_http_handler doctest_impl weaseldb_sources_debug)
+target_compile_options(test_http_handler PRIVATE -UNDEBUG)
+add_test(NAME test_http_handler COMMAND test_http_handler)
+
 # Register with CTest
 add_test(NAME metric_tests COMMAND test_metric)
 

tests/test_http_handler.cpp

@@ -0,0 +1,81 @@
+#include "config.hpp"
+#include "connection.hpp"
+#include "http_handler.hpp"
+#include "server.hpp"
+
+#include <doctest/doctest.h>
+#include <string>
+#include <thread>
+
+TEST_CASE("HTTP pipelined POST requests race condition") {
+  weaseldb::Config config;
+  HttpHandler handler(config);
+  auto server = Server::create(config, handler, {});
+  int fd = server->create_local_connection();
+
+  auto runThread = std::thread{[&]() { server->run(); }};
+
+  // Create a POST request with JSON body that requires parsing
+  std::string json_body = R"({
+    "request_id": "test-123",
+    "leader_id": "leader-1",
+    "read_version": 1,
+    "preconditions": [],
+    "operations": [{"write": {"key": "dGVzdA==", "value": "dmFsdWU="}}]
+  })";
+
+  std::string first_post = "POST /v1/commit HTTP/1.1\r\n"
+                           "Host: localhost\r\n"
+                           "Content-Type: application/json\r\n"
+                           "Content-Length: " +
+                           std::to_string(json_body.size()) +
+                           "\r\n"
+                           "Connection: keep-alive\r\n"
+                           "\r\n" +
+                           json_body;
+
+  std::string second_get = "GET /v1/version HTTP/1.1\r\n"
+                           "Host: localhost\r\n"
+                           "Connection: close\r\n"
+                           "\r\n";
+
+  // Send POST request followed immediately by GET request
+  // This creates a scenario where the GET request starts parsing
+  // while the POST response is being written (triggering the reset)
+  int w1 = write(fd, first_post.c_str(), first_post.size());
+  REQUIRE(w1 == static_cast<int>(first_post.size()));
+
+  int w2 = write(fd, second_get.c_str(), second_get.size());
+  REQUIRE(w2 == static_cast<int>(second_get.size()));
+
+  // Read responses using blocking I/O (deterministic synchronization)
+  char buf[4096];
+  int total_read = 0;
+  int responses_found = 0;
+
+  while (total_read < 4000) {
+    int r = read(fd, buf + total_read, sizeof(buf) - total_read - 1);
+    if (r <= 0)
+      break;
+    total_read += r;
+
+    buf[total_read] = '\0';
+    std::string response(buf, total_read);
+    std::size_t pos = 0;
+    while ((pos = response.find("HTTP/1.1", pos)) != std::string::npos) {
+      responses_found++;
+      pos += 8;
+    }
+
+    if (responses_found >= 2)
+      break;
+  }
+
+  // Should get responses to both requests
+  // Race condition might cause parsing errors or connection issues
+  CHECK(responses_found >= 1); // At minimum should handle first request
+
+  close(fd);
+  server->shutdown();
+  runThread.join();
+}

tests/test_server.cpp

@@ -25,7 +25,6 @@ struct EchoHandler : ConnectionHandler {
 TEST_CASE("Echo test") {
   EchoHandler handler;
   weaseldb::Config config;
-  config.server.io_threads = 1;
   auto server = Server::create(config, handler, {});
   int fd = server->create_local_connection();