added multi threaded pool test

backends/postgres/test/CMakeLists.txt

@@ -12,7 +12,7 @@ list(APPEND CMAKE_MODULE_PATH ${catch2_SOURCE_DIR}/extras)
 include(CTest)
 include(Catch)
 
-set(POSTGRES_CONNECTION_STRING "postgres://test:test123@127.0.0.1:5432/matador_test")
+set(POSTGRES_CONNECTION_STRING "postgres://test:test123@127.0.0.1:15432/test")
 
 configure_file(Connection.hpp.in ${PROJECT_BINARY_DIR}/backends/postgres/test/connection.hpp @ONLY IMMEDIATE)
 

include/matador/sql/connection_pool.hpp

@@ -86,19 +86,21 @@ public:
   }
 
   connection_pointer acquire() {
+    std::unique_lock<std::mutex> lock(mutex_);
+    while (idle_connections_.empty()) {
+      cv.wait(lock);
+    }
+
+    return get_next_connection();
+  }
+
+  connection_pointer try_acquire() {
     std::unique_lock<std::mutex> lock(mutex_);
     if (idle_connections_.empty()) {
       return {nullptr, this};
     }
 
-    pointer next_connection{nullptr};
+    return get_next_connection();
-    for (auto &item : idle_connections_) {
-      next_connection = item.second;
-      auto node = idle_connections_.extract(item.first);
-      inuse_connections_.insert(std::move(node));
-      break;
-    }
-    return {next_connection, this};
   }
 
   connection_pointer acquire(size_t id) {
@@ -151,8 +153,21 @@ public:
   const connection_info &info() const {
     return info_;
   }
+
+private:
+  connection_pointer get_next_connection() {
+    pointer next_connection{nullptr};
+    for (auto &item : idle_connections_) {
+      next_connection = item.second;
+      auto node = idle_connections_.extract(item.first);
+      inuse_connections_.insert(std::move(node));
+      break;
+    }
+    return {next_connection, this};
+  }
 private:
   mutable std::mutex mutex_;
+  std::condition_variable cv;
   std::vector<IdConnection<Connection>> connection_repo_;
   using pointer = IdConnection<Connection>*;
   using connection_map = std::unordered_map<size_t, pointer>;

test/CMakeLists.txt

@@ -34,8 +34,6 @@ add_executable(tests
   models/location.hpp
   models/optional.hpp
   ConvertTest.cpp
-  DummyConnection.hpp
-  DummyConnection.cpp
   EntityQueryBuilderTest.cpp
   models/author.hpp
   models/book.hpp

test/ConnectionPoolTest.cpp

@@ -1,15 +1,42 @@
 #include <catch2/catch_test_macros.hpp>
 
 #include <matador/sql/connection_pool.hpp>
+#include <matador/sql/noop_connection.hpp>
 
-#include "DummyConnection.hpp"
+class AutoResetEvent
+{
+public:
+  AutoResetEvent() : state(false) {}
+  AutoResetEvent(const AutoResetEvent& other) = delete;
+
+  void WaitOne() {
+    std::unique_lock<std::mutex> lock(sync);
+    underlying.wait(lock, [this](){return state.load();});
+  }
+
+  void Set() {
+    std::unique_lock<std::mutex> lock(sync);
+    state = true;
+    underlying.notify_all();
+  }
+
+  void Reset() {
+    std::unique_lock<std::mutex> lock(sync);
+    state = false;
+  }
+
+private:
+  std::condition_variable underlying;
+  std::mutex sync;
+  std::atomic<bool> state;
+};
 
 using namespace matador::sql;
 
 TEST_CASE("Create connection pool", "[connection pool]") {
-  using pool_t = connection_pool<matador::test::DummyConnection>;
+  using pool_t = connection_pool<noop_connection>;
 
-  pool_t pool("sqlite://sqlite.db", 4);
+  pool_t pool("noop://noop.db", 4);
 
   REQUIRE(pool.size() == 4);
   REQUIRE(pool.idle() == 4);
@@ -51,9 +78,9 @@ TEST_CASE("Create connection pool", "[connection pool]") {
 }
 
 TEST_CASE("Acquire connection by id", "[connection pool]") {
-  using pool_t = connection_pool<matador::test::DummyConnection>;
+  using pool_t = connection_pool<noop_connection>;
 
-  pool_t pool("sqlite://sqlite.db", 4);
+  pool_t pool("noop://noop.db", 4);
 
   REQUIRE(pool.size() == 4);
   REQUIRE(pool.idle() == 4);
@@ -79,3 +106,74 @@ TEST_CASE("Acquire connection by id", "[connection pool]") {
   REQUIRE(same_ptr.valid());
   REQUIRE(same_ptr.id() == connection_id);
 }
+
+TEST_CASE("Try acquire connection", "[connection pool][try acquire]") {
+  using pool_t = connection_pool<noop_connection>;
+
+  pool_t pool("noop://noop.db", 1);
+
+  REQUIRE(pool.size() == 1);
+  REQUIRE(pool.idle() == 1);
+  REQUIRE(pool.inuse() == 0);
+
+  auto ptr = pool.try_acquire();
+  REQUIRE(ptr.valid());
+  REQUIRE(ptr.id());
+  REQUIRE(ptr.id().value() > 0);
+  REQUIRE(ptr->is_open());
+  REQUIRE(pool.size() == 1);
+  REQUIRE(pool.idle() == 0);
+  REQUIRE(pool.inuse() == 1);
+
+  auto ptr2 = pool.try_acquire();
+  REQUIRE(!ptr2.valid());
+
+  pool.release(ptr);
+  REQUIRE(!ptr.valid());
+  REQUIRE(pool.size() == 1);
+  REQUIRE(pool.idle() == 1);
+  REQUIRE(pool.inuse() == 0);
+
+  ptr2 = pool.try_acquire();
+  REQUIRE(ptr2.valid());
+  REQUIRE(ptr2.id());
+  REQUIRE(ptr2.id().value() > 0);
+  REQUIRE(ptr2->is_open());
+  REQUIRE(pool.size() == 1);
+  REQUIRE(pool.idle() == 0);
+  REQUIRE(pool.inuse() == 1);
+
+  pool.release(ptr2);
+
+  AutoResetEvent reset_event1;
+  AutoResetEvent reset_event2;
+  AutoResetEvent reset_event3;
+
+  std::thread t([&reset_event1, &reset_event2, &reset_event3, &pool]() {
+    auto c1 = pool.acquire();
+    REQUIRE(c1.valid());
+    REQUIRE(c1.id());
+    REQUIRE(c1.id().value() > 0);
+
+    reset_event1.Set();
+
+    reset_event2.WaitOne();
+    pool.release(c1);
+    REQUIRE(!c1.valid());
+    reset_event3.Set();
+  });
+  reset_event1.WaitOne();
+
+  ptr2 = pool.try_acquire();
+  REQUIRE(!ptr2.valid());
+
+  reset_event2.Set();
+
+  reset_event3.WaitOne();
+  ptr2 = pool.try_acquire();
+  REQUIRE(ptr2.valid());
+  REQUIRE(ptr2.id());
+  REQUIRE(ptr2.id().value() > 0);
+
+  t.join();
+}

test/DummyConnection.cpp

@@ -1,28 +0,0 @@
-#include "DummyConnection.hpp"
-
-namespace matador::test {
-
-DummyConnection::DummyConnection(sql::connection_info info)
-: connection_info_(std::move(info))
-{}
-
-DummyConnection::DummyConnection(const std::string &dns)
-: DummyConnection(sql::connection_info::parse(dns))
-{}
-
-void DummyConnection::open()
-{
-  is_open_ = true;
-}
-
-void DummyConnection::close()
-{
-  is_open_ = false;
-}
-
-bool DummyConnection::is_open() const
-{
-  return is_open_;
-}
-
-}

test/DummyConnection.hpp

@@ -1,30 +0,0 @@
-#ifndef QUERY_DUMMYCONNECTION_HPP
-#define QUERY_DUMMYCONNECTION_HPP
-
-#include "matador/sql/connection_info.hpp"
-
-namespace matador::test {
-
-class DummyConnection
-{
-public:
-  explicit DummyConnection(sql::connection_info info);
-  explicit DummyConnection(const std::string& dns);
-  DummyConnection(const DummyConnection &x) = default;
-  DummyConnection& operator=(const DummyConnection &x) = default;
-  DummyConnection(DummyConnection &&x) noexcept = default;
-  DummyConnection& operator=(DummyConnection &&x) noexcept = default;
-  ~DummyConnection() = default;
-
-  void open();
-  void close();
-  [[nodiscard]] bool is_open() const;
-
-private:
-  sql::connection_info connection_info_;
-
-  bool is_open_{};
-};
-
-}
-#endif //QUERY_DUMMYCONNECTION_HPP