Refactor ComponentInterface to use node interfaces

[domire8]

Description

• Use node interfaces in ros:iron to avoid templated ComponentInterface #32

This is kind of a long shot and has low priority, but I wanted to write it down while it's fresh.

Even though the changes are big, they are not as complex in my opinion. What you need to do is get a pointer to all node interfaces rclcpp::node_interfaces::NodeInterfaces<ALL_RCLCPP_NODE_INTERFACES> to be able to replace all occurrences of NodeT::foo.

So basically, most of the changes are in the style of this->get_logger() that becomes this->node_logging_->get_logger() (same for parameters, clock). Services and subscriptions are slightly more complicated, you have to do

auto subscription = rclcpp::create_subscription<modulo_core::EncodedState>(
            this->node_parameters_, this->node_topics_, topic_name, this->qos_,
            subscription_handler->get_callback(user_callback));

i.e. you have to work with the node_parameters_ and node_topics_ interfaces.

Another nice consequence is that the PublisherType does not have to be a class attribute anymore, but can just be passed as an argument to create_output. Apart from that, I just updated the tests (that got much simpler without these if else blocks based on the TypeParam).

The CI will not build obviously though.

Review guidelines

Estimated Time of Review: 20 minutes
Review by commit

[eeberhard]

It's been sitting for a while and I've looked over a couple of times, finally I gave it some proper thought. Great start! Will be good to get this moving again. For the derived component classes, were you planning do something along the following lines?

// declare double inheritance
class Component : public rclcpp::Node, public ComponentInterface {
...
}

// construct the ComponentInterface after the Node, using the Node methods that are already constructed
Component::Component(const rclcpp::NodeOptions& node_options, const std::string& fallback_name) :
    rclcpp::Node(utilities::parse_node_name(node_options, fallback_name), node_options), ComponentInterface(
    std::make_shared<rclcpp::node_interfaces::NodeInterfaces<ALL_RCLCPP_NODE_INTERFACES>>(
        rclcpp::Node::get_node_base_interface(), rclcpp::Node::get_node_clock_interface(),
        rclcpp::Node::get_node_graph_interface(), rclcpp::Node::get_node_logging_interface(),
        rclcpp::Node::get_node_parameters_interface(), rclcpp::Node::get_node_services_interface(),
        rclcpp::Node::get_node_time_source_interface(), rclcpp::Node::get_node_timers_interface(),
        rclcpp::Node::get_node_topics_interface(), rclcpp::Node::get_node_waitables_interface())), started_(false) {
  this->add_predicate("is_finished", false);
}

I believe that would work!

[domire8]

Yes indeed, see here

Branch refactor/node-interfaces. I just wanted to split it in reviewable chunks because we'll be able to put most of the code in the .cpp file now but that would have been messy..