Handle exceptions in event publisher and discovery threads

- Exceptions potentially may come from the underlying node operations
when we are invalidating context via rclcpp::shutdown(). We need to have
possibility to correct finish recording in this case.

Signed-off-by: Michael Orlov <michael.orlov@apex.ai>

rosbag2_transport/src/rosbag2_transport/recorder.cpp

@@ -285,11 +285,12 @@ void RecorderImpl::record()
       response->paused = is_paused();
     });
 
+  split_event_pub_ =
+    node->create_publisher<rosbag2_interfaces::msg::WriteSplitEvent>("events/write_split", 1);
+
   // Start the thread that will publish events
   event_publisher_thread_ = std::thread(&RecorderImpl::event_publisher_thread_main, this);
 
-  split_event_pub_ =
-    node->create_publisher<rosbag2_interfaces::msg::WriteSplitEvent>("events/write_split", 1);
   rosbag2_cpp::bag_events::WriterEventCallbacks callbacks;
   callbacks.write_split_callback =
     [this](rosbag2_cpp::bag_events::BagSplitInfo & info) {
@@ -328,7 +329,17 @@ void RecorderImpl::event_publisher_thread_main()
       auto message = rosbag2_interfaces::msg::WriteSplitEvent();
       message.closed_file = bag_split_info_.closed_file;
       message.opened_file = bag_split_info_.opened_file;
-      split_event_pub_->publish(message);
+      try {
+        split_event_pub_->publish(message);
+      } catch (const std::exception & e) {
+        RCLCPP_ERROR_STREAM(
+          node->get_logger(),
+          "Failed to publish message on '/events/write_split' topic. \nError: " << e.what());
+      } catch (...) {
+        RCLCPP_ERROR_STREAM(
+          node->get_logger(),
+          "Failed to publish message on '/events/write_split' topic.");
+      }
     }
   }
   RCLCPP_INFO(node->get_logger(), "Event publisher thread: Exiting");
@@ -373,19 +384,26 @@ bool RecorderImpl::is_paused()
 void RecorderImpl::topics_discovery()
 {
   while (rclcpp::ok() && stop_discovery_ == false) {
-    auto topics_to_subscribe =
-      get_requested_or_available_topics();
-    for (const auto & topic_and_type : topics_to_subscribe) {
-      warn_if_new_qos_for_subscribed_topic(topic_and_type.first);
-    }
-    auto missing_topics = get_missing_topics(topics_to_subscribe);
-    subscribe_topics(missing_topics);
+    try {
+      auto topics_to_subscribe = get_requested_or_available_topics();
+      for (const auto & topic_and_type : topics_to_subscribe) {
+        warn_if_new_qos_for_subscribed_topic(topic_and_type.first);
+      }
+      auto missing_topics = get_missing_topics(topics_to_subscribe);
+      subscribe_topics(missing_topics);
 
-    if (!record_options_.topics.empty() && subscriptions_.size() == record_options_.topics.size()) {
-      RCLCPP_INFO(
-        node->get_logger(),
-        "All requested topics are subscribed. Stopping discovery...");
-      return;
+      if (!record_options_.topics.empty() &&
+        subscriptions_.size() == record_options_.topics.size())
+      {
+        RCLCPP_INFO(
+          node->get_logger(),
+          "All requested topics are subscribed. Stopping discovery...");
+        return;
+      }
+    } catch (const std::exception & e) {
+      RCLCPP_ERROR_STREAM(node->get_logger(), "Failure in topics discovery.\nError: " << e.what());
+    } catch (...) {
+      RCLCPP_ERROR_STREAM(node->get_logger(), "Failure in topics discovery.");
     }
     std::this_thread::sleep_for(record_options_.topic_polling_interval);
   }