component_container.cpp

// Copyright 2019 Open Source Robotics Foundation, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include <memory>

#include "rclcpp/executors/single_threaded_executor.hpp"
#include "rclcpp/utilities.hpp"

#include "rclcpp_components/component_manager.hpp"

int main(int argc, char * argv[])
{
  /// Component container with a single-threaded executor.
  rclcpp::init(argc, argv);

  std::shared_ptr<rclcpp::Executor> exec;
  auto node = std::make_shared<rclcpp_components::ComponentManager>();

  const auto exec_type = node->get_parameter("executor_type").as_string();
  if (exec_type == "SingleThreadedExecutor" || exec_type == "No Executor") {
    // Default executor for ComponentContainer is SingleThreadedExecutor, because of
    // backward compatibility.
    exec = std::make_shared<rclcpp::executors::SingleThreadedExecutor>();
  } else if (exec_type == "MultiThreadedExecutor") {
    if (node->has_parameter("thread_num")) {
      const auto thread_num = node->get_parameter("thread_num").as_int();
      exec = std::make_shared<rclcpp::executors::MultiThreadedExecutor>(
          rclcpp::ExecutorOptions{}, thread_num);
    } else {
      exec = std::make_shared<rclcpp::executors::MultiThreadedExecutor>();
    }
  } else if (exec_type == "EventsExecutor") {
    exec = std::make_shared<rclcpp::experimental::executors::EventsExecutor>();
  } else {
    RCLCPP_ERROR(node->get_logger(), "Unknown executor type %s", exec_type.c_str());
    return 1;
  }

  node->set_executor(exec);

  exec->add_node(node);
  exec->spin();

  return 0;
}