[rolling] image_publisher: Fix loading of the camera info parameters …

…on startup (#983)

As described in
#965 camera info
is not loaded from the file on node initialization, but only when the
parameter is reloaded.

This PR resolves this issue and should be straightforward to port it to
`Humble`, `Iron` and `Jazzy`.

(cherry picked from commit 847920b)

image_publisher/src/image_publisher.cpp

@@ -74,41 +74,48 @@ ImagePublisher::ImagePublisher(
   auto param_change_callback =
     [this](std::vector<rclcpp::Parameter> parameters) -> rcl_interfaces::msg::SetParametersResult
     {
+      bool call_init = false;
+      bool call_reconfigure = false;
+
       auto result = rcl_interfaces::msg::SetParametersResult();
       result.successful = true;
       for (auto parameter : parameters) {
         if (parameter.get_name() == "filename") {
           filename_ = parameter.as_string();
           RCLCPP_INFO(get_logger(), "Reset filename as '%s'", filename_.c_str());
-          ImagePublisher::onInit();
-          return result;
+          call_init = true;
         } else if (parameter.get_name() == "field_of_view") {
           field_of_view_ = parameter.as_double();
           RCLCPP_INFO(get_logger(), "Reset field_of_view as '%f'", field_of_view_);
-          ImagePublisher::onInit();
-          return result;
+          call_init = true;
         } else if (parameter.get_name() == "flip_horizontal") {
           flip_horizontal_ = parameter.as_bool();
           RCLCPP_INFO(get_logger(), "Reset flip_horizontal as '%d'", flip_horizontal_);
-          ImagePublisher::onInit();
-          return result;
+          call_init = true;
         } else if (parameter.get_name() == "flip_vertical") {
           flip_vertical_ = parameter.as_bool();
           RCLCPP_INFO(get_logger(), "Reset flip_vertical as '%d'", flip_vertical_);
-          ImagePublisher::onInit();
-          return result;
+          call_init = true;
         } else if (parameter.get_name() == "frame_id") {
           frame_id_ = parameter.as_string();
           RCLCPP_INFO(get_logger(), "Reset frame_id as '%s'", frame_id_.c_str());
         } else if (parameter.get_name() == "publish_rate") {
           publish_rate_ = parameter.as_double();
           RCLCPP_INFO(get_logger(), "Reset publish_rate as '%lf'", publish_rate_);
+          call_reconfigure = true;
         } else if (parameter.get_name() == "camera_info_url") {
           camera_info_url_ = parameter.as_string();
-          RCLCPP_INFO(get_logger(), "Reset camera_info_url as '%s'", camera_info_url_.c_str());
+          RCLCPP_INFO(get_logger(), "Reset camera_info_rul as '%s'", camera_info_url_.c_str());
+          call_reconfigure = true;
         }
       }
-      ImagePublisher::reconfigureCallback();
+      // reconfigureCallback() is called within onInit() so there is no need to call it twice
+      if (call_reconfigure && !call_init) {
+        ImagePublisher::reconfigureCallback();
+      } else if (call_init) {
+        ImagePublisher::onInit();
+      }
+
       return result;
     };
   on_set_parameters_callback_handle_ = this->add_on_set_parameters_callback(param_change_callback);
@@ -238,9 +245,7 @@ void ImagePublisher::onInit()
   camera_info_.p = {f_approx, 0, static_cast<float>(camera_info_.width / 2), 0, 0, f_approx,
     static_cast<float>(camera_info_.height / 2), 0, 0, 0, 1, 0};
 
-  timer_ = this->create_wall_timer(
-    std::chrono::milliseconds(static_cast<int>(1000 / publish_rate_)),
-    std::bind(&ImagePublisher::doWork, this));
+  ImagePublisher::reconfigureCallback();
 }
 
 }  // namespace image_publisher