Fixed the unloading severe warning by adding a shutdown function in

include/network_bridge/network_bridge.hpp

@@ -64,6 +64,14 @@ class NetworkBridge : public rclcpp::Node
    */
   virtual void initialize();
 
+  /**
+   * @brief Destroy the objects created by the bridge
+   *
+   * It should be called once spinning is over, and before the shared pointer is reset, to
+   * make sure the garbage collector can run
+   */
+  virtual void shutdown();
+
 protected:
   /**
    * @brief Loads default parameters and creates subsciption managers for each topic.

src/network_bridge.cpp

@@ -43,13 +43,7 @@ NetworkBridge::NetworkBridge(const std::string & node_name)
 
 NetworkBridge::~NetworkBridge()
 {
-  network_interface_->close();
-  network_interface_.reset();
-
-  network_check_timer_.reset();
-  sub_mgrs_.clear();
-  timers_.clear();
-  publishers_.clear();
+  shutdown();
 }
 
 void NetworkBridge::initialize()
@@ -59,6 +53,19 @@ void NetworkBridge::initialize()
   network_interface_->open();
 }
 
+void NetworkBridge::shutdown()
+{
+  if (network_interface_) {
+    network_interface_->close();
+  }
+  network_interface_.reset();
+
+  network_check_timer_.reset();
+  sub_mgrs_.clear();
+  timers_.clear();
+  publishers_.clear();
+}
+
 void NetworkBridge::load_parameters()
 {
   this->declare_parameter(
@@ -422,6 +429,7 @@ int main(int argc, char ** argv)
   node->initialize();
 
   rclcpp::spin(node);
+  node->shutdown();
   node.reset();
 
   rclcpp::shutdown();

src/network_interfaces/tcp_interface.cpp

@@ -102,11 +102,13 @@ void TcpInterface::close()
   try {
     packet_thread_.join();
   } catch (std::system_error &) {
+    // the thread was not started
   }
   io_context_.stop();
   try {
     io_thread_.join();
   } catch (std::system_error &) {
+    // the thread was not started
   }
 }
 

src/network_interfaces/udp_interface.cpp

@@ -59,7 +59,11 @@ void UdpInterface::open()
 void UdpInterface::close()
 {
   io_context_.stop();
-  io_thread_.join();
+  try {
+    io_thread_.join();
+  } catch (std::system_error &) {
+    // the thread was not started
+  }
 }
 
 void UdpInterface::load_parameters()