json_utils.hpp

// Copyright (c) 2025 Alberto J. Tudela Roldán
// Copyright (c) 2025 Grupo Avispa, DTE, Universidad de Málaga
//
// 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.
 
#ifndef NAV2_BEHAVIOR_TREE__JSON_UTILS_HPP_
#define NAV2_BEHAVIOR_TREE__JSON_UTILS_HPP_
 
#include <string>
#include <set>
#include <vector>
 
#include "rclcpp/time.hpp"
#include "rclcpp/node.hpp"
#include "behaviortree_cpp/json_export.h"
#include "geometry_msgs/msg/point.hpp"
#include "geometry_msgs/msg/pose_stamped.hpp"
#include "geometry_msgs/msg/quaternion.hpp"
#include "nav_msgs/msg/goals.hpp"
#include "nav_msgs/msg/path.hpp"
 
// The follow templates are required when using Groot 2 to visualize the BT. They
// convert the data types into JSON format easy for visualization.
 
namespace builtin_interfaces::msg
{
 
BT_JSON_CONVERTER(builtin_interfaces::msg::Time, msg)
{
  add_field("sec", &msg.sec);
  add_field("nanosec", &msg.nanosec);
}
 
}  // namespace builtin_interfaces::msg
 
namespace std_msgs::msg
{
 
BT_JSON_CONVERTER(std_msgs::msg::Header, msg)
{
  add_field("stamp", &msg.stamp);
  add_field("frame_id", &msg.frame_id);
}
 
}  // namespace std_msgs::msg
 
namespace geometry_msgs::msg
{
 
BT_JSON_CONVERTER(geometry_msgs::msg::Point, msg)
{
  add_field("x", &msg.x);
  add_field("y", &msg.y);
  add_field("z", &msg.z);
}
 
BT_JSON_CONVERTER(geometry_msgs::msg::Quaternion, msg)
{
  add_field("x", &msg.x);
  add_field("y", &msg.y);
  add_field("z", &msg.z);
  add_field("w", &msg.w);
}
 
BT_JSON_CONVERTER(geometry_msgs::msg::Pose, msg)
{
  add_field("position", &msg.position);
  add_field("orientation", &msg.orientation);
}
 
BT_JSON_CONVERTER(geometry_msgs::msg::PoseStamped, msg)
{
  add_field("header", &msg.header);
  add_field("pose", &msg.pose);
}
 
}  // namespace geometry_msgs::msg
 
namespace nav_msgs::msg
{
 
BT_JSON_CONVERTER(nav_msgs::msg::Goals, msg)
{
  add_field("header", &msg.header);
  add_field("goals", &msg.goals);
}
 
BT_JSON_CONVERTER(nav_msgs::msg::Path, msg)
{
  add_field("header", &msg.header);
  add_field("poses", &msg.poses);
}
 
}  // namespace nav_msgs::msg
 
 
namespace std
{
 
inline void from_json(const nlohmann::json & js, std::chrono::milliseconds & dest)
{
  if (js.contains("ms")) {
    dest = std::chrono::milliseconds(js.at("ms").get<int>());
  } else {
    throw std::runtime_error("Invalid JSON for std::chrono::milliseconds");
  }
}
 
inline void to_json(nlohmann::json & js, const std::chrono::milliseconds & src)
{
  js["__type"] = "std::chrono::milliseconds";
  js["ms"] = src.count();
}
 
}  // namespace std
 
#endif  // NAV2_BEHAVIOR_TREE__JSON_UTILS_HPP_