Add BagSplitInfo service call on bag close (#1422)

- Note: The `BagSplitInfo::opened_file` will have empty string to
indicate that it was "bag close" and not bag split event.

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

rosbag2_cpp/include/rosbag2_cpp/bag_events.hpp

@@ -165,6 +165,14 @@ class EventCallbackManager
     return false;
   }
 
+  /**
+   * \brief Delete all callbacks
+   */
+  void delete_all_callbacks()
+  {
+    callbacks_.clear();
+  }
+
   /**
    * \brief Execute all callbacks registered for the given event.
    *

rosbag2_cpp/src/rosbag2_cpp/writers/sequential_writer.cpp

@@ -62,6 +62,10 @@ SequentialWriter::SequentialWriter(
 
 SequentialWriter::~SequentialWriter()
 {
+  // Deleting all callbacks before calling close(). Calling callbacks from destructor is not safe.
+  // Callbacks likely was created after SequentialWriter object and may point to the already
+  // destructed objects.
+  callback_manager_.delete_all_callbacks();
   close();
 }
 
@@ -172,7 +176,13 @@ void SequentialWriter::close()
     metadata_io_->write_metadata(base_folder_, metadata_);
   }
 
-  storage_.reset();  // Necessary to ensure that the storage is destroyed before the factory
+  if (storage_) {
+    auto info = std::make_shared<bag_events::BagSplitInfo>();
+    info->closed_file = storage_->get_relative_file_path();
+    storage_.reset();  // Destroy storage before calling WRITE_SPLIT callback to make sure that
+    // bag file was closed before callback call.
+    callback_manager_.execute_callbacks(bag_events::BagEvent::WRITE_SPLIT, info);
+  }
   storage_factory_.reset();
 }
 

rosbag2_cpp/test/rosbag2_cpp/test_sequential_writer.cpp

@@ -642,6 +642,66 @@ TEST_F(SequentialWriterTest, split_event_calls_callback)
   EXPECT_EQ(opened_file, fake_storage_uri_);
 }
 
+TEST_F(SequentialWriterTest, split_event_calls_on_writer_close)
+{
+  const int message_count = 7;
+
+  ON_CALL(
+    *storage_,
+    write(An<std::shared_ptr<const rosbag2_storage::SerializedBagMessage>>())).WillByDefault(
+    [this](std::shared_ptr<const rosbag2_storage::SerializedBagMessage>) {
+      fake_storage_size_ += 1;
+    });
+
+  ON_CALL(*storage_, get_bagfile_size).WillByDefault(
+    [this]() {
+      return fake_storage_size_.load();
+    });
+
+  ON_CALL(*metadata_io_, write_metadata).WillByDefault(
+    [this](const std::string &, const rosbag2_storage::BagMetadata & metadata) {
+      fake_metadata_ = metadata;
+    });
+
+  ON_CALL(*storage_, get_relative_file_path).WillByDefault(
+    [this]() {
+      return fake_storage_uri_;
+    });
+
+  auto sequential_writer = std::make_unique<rosbag2_cpp::writers::SequentialWriter>(
+    std::move(storage_factory_), converter_factory_, std::move(metadata_io_));
+  writer_ = std::make_unique<rosbag2_cpp::Writer>(std::move(sequential_writer));
+
+  auto message = std::make_shared<rosbag2_storage::SerializedBagMessage>();
+  message->topic_name = "test_topic";
+
+  storage_options_.max_bagfile_size = 0;
+
+  bool callback_called = false;
+  std::string closed_file, opened_file;
+  rosbag2_cpp::bag_events::WriterEventCallbacks callbacks;
+  callbacks.write_split_callback =
+    [&callback_called, &closed_file, &opened_file](rosbag2_cpp::bag_events::BagSplitInfo & info) {
+      closed_file = info.closed_file;
+      opened_file = info.opened_file;
+      callback_called = true;
+    };
+  writer_->add_event_callbacks(callbacks);
+
+  writer_->open(storage_options_, {"rmw_format", "rmw_format"});
+  writer_->create_topic({"test_topic", "test_msgs/BasicTypes", "", "", ""});
+
+  for (auto i = 0; i < message_count; ++i) {
+    writer_->write(message);
+  }
+  writer_->close();
+
+  ASSERT_TRUE(callback_called);
+  auto expected_closed = rcpputils::fs::path(storage_options_.uri) / (storage_options_.uri + "_0");
+  EXPECT_EQ(closed_file, expected_closed.string());
+  EXPECT_TRUE(opened_file.empty());
+}
+
 TEST_P(ParametrizedTemporaryDirectoryFixture, split_bag_metadata_has_full_duration) {
   const std::vector<std::pair<rcutils_time_point_value_t, uint32_t>> fake_messages {
     {100, 1},