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topic package from openrobotics repo

ros2_ballbot ros2_cartpole ros2_double_integrator ros2_quadrotor ros2_robot_vacuum ros2_vacuum_gazebo ros2_vacuum_slam action common_utils composition executors gazebo_camera gazebo_spawner lifecycle params pointcloud_subsriber rviz service system_monitor tf2_demos timer topic tutorials_msgs urdf decomp_ros decomp_ros_msgs decomp_ros_utils decomp_test_node ros2_math casadi_cpp casadi_python casadi_tutorials nav2_linear_quadratic_regulator_controller motion_model mpc_controller pid_controller robotic_assets ros2_controller ros2_controller_msgs waypoint_generator behavior_tree bspline carlike_simulator fast_methods forest_map_generator gridmap_ros map_generator nav2_demos a_star_planner breadth_first_search_planner bug_planner cubic_spline_planner d_star_lite_planner d_star_planner depth_first_planner dijkstra_planner dubins_path_planner eta3_spline_planner flow_filed_planner frenet_optimal_trajectory_planner greedy_best_first_search_planner hybrid_a_star_planner informed_rrt_star_planner nav2_straightline_planner path_planning potential_field_planner quintic_polynomials_planner rrt_dubins_planner rrt_planner rrt_star_planner state_lattice_planner voronoi_planner wave_front_planner cgmres_nmpc_tracking lqr_speed_steer_control_tracking model_predictive_speed_steer_control_tracking path_tracking pure_pursuit_tracking rear_wheel_feedback_tracking stanley_controller_tracking ros2_navigation ros2_system_test sdf_tools trajectory local_sensing multi_map_server odom_visualization pose_utils quadrotor_msgs so3_disturbance_generator so3_quadrotor_simulator uav_utils visualization_tools voronoi_layer quad_behavior_tree quad_bringup quad_bt_navigator quad_common quad_controller quad_core quad_costmap quad_global_planner quad_local_planner quad_logger quad_map_server quad_msgs quad_nmpc_controller quad_planner quad_robot_driver quad_rviz_plugins a1_description a1_simulation quad_gazebo spirit_description spirit_gazebo spirit_simulation quad_system_tests quad_teleop quad_utils ros2_quadruped gazebo_examples sam_bot_description velodyne_description velodyne_gazebo_plugins velodyne_simulator

API Docs
Browse Code

Package Summary

Tags	No category tags.
Version	0.0.0
License	TODO: License declaration
Build type	AMENT_CMAKE
Use	RECOMMENDED

Repository Summary

Checkout URI	https://github.com/duyongquan/openrobotics.git
VCS Type	git
VCS Version	main
Last Updated	2024-01-16
Dev Status	UNMAINTAINED
CI status	No Continuous Integration
Released	UNRELEASED
Tags	No category tags.
Contributing	Help Wanted (0) Good First Issues (0) Pull Requests to Review (0)

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quan

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ros2_basics/topic/README.md

ros2_tutorials —— topic使用 Part I 订阅者(Publisher)

1 tutorial 1(initial_env_test)

1.1 功能介绍

环境搭建，打印一句话

1.2 代码

头文件tutorials_topic_demo1_initial_env.hpp

#include <chrono>
#include <memory>
#include <string>

#include "rclcpp/rclcpp.hpp"
#include "std_msgs/msg/string.hpp"


namespace ros2_tutorials
{
namespace topic
{

class EmptyNode : public rclcpp::Node
{
public:
    EmptyNode();
    ~EmptyNode();
};

}  // namespace topic
}  // namespace ros2_tutorials

tutorials_topic_demo1_initial_env.cpp

#include "topic/tutorials_topic_demo1_initial_env.hpp"

namespace ros2_tutorials
{
namespace topic
{

EmptyNode::EmptyNode()
: Node("empty")
{
    RCLCPP_INFO(get_logger(), "Creating empty node.");
}

EmptyNode::~EmptyNode()
{
}

}  // namespace topic
}  // namespace ros2_tutorials

测试文件tutorials_topic_demo1_initial_env_test.cpp

#include "topic/tutorials_topic_demo1_initial_env.hpp"

int main(int argc, char ** argv)
{
  rclcpp::init(argc, argv);
  auto empty_node = std::make_shared<ros2_tutorials::topic::EmptyNode>();
  rclcpp::spin(empty_node);
  rclcpp::shutdown();
  return 0;
}

1.3 编译

colcon build  --packages-up-to topic

1.4 运行

source环境变量

source install/setup.zsh

方式1

cd install/topic/lib/topic/
./tutorial.topic.initial_env_test

方式2

ros2 launch topic tutorials_topic_demo1_initial_env_test_launch.py

1.5 运行结果

topic_tutorial.topic.initial_env_test

2 tutorial 2(member_function_test)

2.1 功能介绍

创建一个消息发布者，每隔500ms发布一次消息“’Hello, world!”

2.2 代码

头文件tutorials_topic_demo2_member_function.hpp

class MinimalPublisher : public rclcpp::Node
{
public:
    MinimalPublisher();
    ~MinimalPublisher();

private:
    void HandleTimerCallback();
    rclcpp::TimerBase::SharedPtr timer_;
    rclcpp::Publisher<std_msgs::msg::String>::SharedPtr publisher_;
    size_t count_;
};

源文件tutorials_topic_demo2_member_function.cpp

MinimalPublisher::MinimalPublisher()
: Node("minimal_publisher"), count_(0)
{
    publisher_ = this->create_publisher<std_msgs::msg::String>("topic", 10);
    timer_ = this->create_wall_timer(
        500ms, std::bind(&MinimalPublisher::HandleTimerCallback, this));
}

MinimalPublisher::~MinimalPublisher()
{
}

void MinimalPublisher::HandleTimerCallback()
{
    auto message = std_msgs::msg::String();
    message.data = "Hello, world! " + std::to_string(count_++);
    RCLCPP_INFO(this->get_logger(), "Publishing: '%s'", message.data.c_str());
    publisher_->publish(message);
}

测试文件tutorials_topic_demo2_member_function_test.cpp

#include "topic/tutorials_topic_demo2_member_function.hpp"

int main(int argc, char ** argv)
{
  rclcpp::init(argc, argv);
  auto publisher_node = std::make_shared<ros2_tutorials::topic::MinimalPublisher>();
  rclcpp::spin(publisher_node);
  rclcpp::shutdown();
  return 0;
}

2.3 编译

colcon build  --packages-up-to topic

2.4 运行

source环境变量

source install/setup.zsh

方式1

cd install/topic/lib/topic/
./tutorial.topic.tutorial.topic.member_function_test

方式2

ros2 launch topic tutorials_topic_demo2_member_function_test_launch.py

2.5 运行结果

tutorials_topic.member_function_test

3 tutorial 3(lambda_test)

3.1 功能介绍

创建一个消息发布者（处理函数是lambda表达式），每隔500ms发布一次消息“’Hello, world!”

3.2 代码

头文件tutorials_topic_demo3_lambda_test.hpp

class MinimalPublisherWithLambda : public rclcpp::Node
{
public:
  MinimalPublisherWithLambda();

private:
  rclcpp::TimerBase::SharedPtr timer_;
  rclcpp::Publisher<std_msgs::msg::String>::SharedPtr publisher_;
  size_t count_;
};

源文件tutorials_topic_demo3_lambda_test.cpp

MinimalPublisherWithLambda::MinimalPublisherWithLambda()
 : Node("lambda_minimal_publisher"), count_(0)
{
    publisher_ = this->create_publisher<std_msgs::msg::String>("topic", 10);
    auto timer_callback = [this]() -> void {
            auto message = std_msgs::msg::String();
            message.data = "Hello, world! " + std::to_string(this->count_++);
            RCLCPP_INFO(this->get_logger(), "Publishing: '%s'", message.data.c_str());
            this->publisher_->publish(message);
        };
    timer_ = this->create_wall_timer(500ms, timer_callback);
}

测试文件tutorials_topic_demo3_lambda_test.cpp

#include "topic/tutorials_topic_demo3_lambda.hpp"

int main(int argc, char ** argv)
{
  rclcpp::init(argc, argv);
  auto empty_node = std::make_shared<ros2_tutorials::topic::MinimalPublisherWithLambda>();
  rclcpp::spin(empty_node);
  rclcpp::shutdown();
  return 0;
}

3.3 编译

colcon build  --packages-up-to topic

3.4 运行

source环境变量

source install/setup.zsh

方式1

cd install/topic/lib/topic/
./tutorial.topic.tutorial.topic.lambda_test

方式2

ros2 launch topic tutorials_topic_demo3_lambda_test_launch.py

3.5 运行结果

tutorials_topic.member_function_test

4 tutorial 4(lambda_test)

4.1 功能介绍

创建一个消息发布，每隔500ms发布一次消息“’Hello, world!”

4.2 代码

测试文件tutorials_topic_demo4_not_composable_test.cpp

#include <chrono>
#include <string>

#include "rclcpp/rclcpp.hpp"
#include "std_msgs/msg/string.hpp"

using namespace std::chrono_literals;

/* We do not recommend this style anymore, because composition of multiple
 * nodes in the same executable is not possible. Please see one of the subclass
 * examples for the "new" recommended styles. This example is only included
 * for completeness because it is similar to "classic" standalone ROS nodes. 
 */
int main(int argc, char * argv[])
{
  rclcpp::init(argc, argv);
  auto node = rclcpp::Node::make_shared("not_composable_minimal_publisher");
  auto publisher = node->create_publisher<std_msgs::msg::String>("topic", 10);
  std_msgs::msg::String message;
  auto publish_count = 0;
  rclcpp::WallRate loop_rate(500ms);

  while (rclcpp::ok()) {
    message.data = "Hello, world! " + std::to_string(publish_count++);
    RCLCPP_INFO(node->get_logger(), "Publishing: '%s'", message.data.c_str());
    try {
      publisher->publish(message);
      rclcpp::spin_some(node);
    } catch (const rclcpp::exceptions::RCLError & e) {
      RCLCPP_ERROR(
        node->get_logger(),
        "unexpectedly failed with %s",
        e.what());
    }
    loop_rate.sleep();
  }
  rclcpp::shutdown();
  return 0;
}

4.3 编译

colcon build  --packages-up-to topic

4.4 运行

source环境变量

source install/setup.zsh

方式1

cd install/topic/lib/topic/
./tutorial.topic.tutorial.topic.not_composable_test

方式2

ros2 launch topic tutorials.topic.demo4_not_composable_test.launch.py

4.5 运行结果

tutorials_topic.member_function_test

Part II 订阅者(Subscriber)

5 tutorial 5(订阅器member_function)

5.1 功能介绍

创建一个消息发布器和一个消息订阅器，每隔500ms发布一次消息“’Hello, world!”，而接受者订阅器每隔500ms会收到发布者的数据信息

5.2 代码

头文件tutorials_topic_demo2_member_function.hpp

在原来的头文件上修改，加上 MinimalSubscriber类

class MinimalPublisher : public rclcpp::Node
{
public:
    MinimalPublisher();
    ~MinimalPublisher();

private:
    void HandleTimerCallback();
    rclcpp::TimerBase::SharedPtr timer_;
    rclcpp::Publisher<std_msgs::msg::String>::SharedPtr publisher_;
    size_t count_;
};

class MinimalSubscriber : public rclcpp::Node
{
public:
  MinimalSubscriber();

private:
  void HandleTopicCallback(const std_msgs::msg::String::SharedPtr msg) const;

  rclcpp::Subscription<std_msgs::msg::String>::SharedPtr subscription_;
};

源文件 tutorials_topic_demo2_member_function.cpp

MinimalSubscriber::MinimalSubscriber()
: Node("member_minimal_subscriber")
{
    subscription_ = this->create_subscription<std_msgs::msg::String>(
        "topic", 10, std::bind(&MinimalSubscriber::HandleTopicCallback, this, std::placeholders::_1));
}

void MinimalSubscriber::HandleTopicCallback(const std_msgs::msg::String::SharedPtr msg) const
{
    RCLCPP_INFO(this->get_logger(), "I heard: '%s'", msg->data.c_str());
}

测试文件tutorials_topic_demo2_member_function_test.cpp

#include "topic/tutorials_topic_demo2_member_function.hpp"

// int main(int argc, char ** argv)
// {
//   rclcpp::init(argc, argv);
//   auto publisher_node = std::make_shared<ros2_tutorials::topic::MinimalPublisher>();
//   rclcpp::spin(publisher_node);
//   rclcpp::shutdown();
//   return 0;
// }

int main(int argc, char * argv[])
{
  rclcpp::init(argc, argv);

  // You MUST use the MultiThreadedExecutor to use, well, multiple threads
  rclcpp::executors::MultiThreadedExecutor executor;
  auto publisher_node = std::make_shared<ros2_tutorials::topic::MinimalPublisher>();
  auto subscriber_node = std::make_shared<ros2_tutorials::topic::MinimalSubscriber>();  // This contains BOTH subscriber callbacks.
                                                        // They will still run on different threads
                                                        // One Node. Two callbacks. Two Threads
  executor.add_node(publisher_node);
  executor.add_node(subscriber_node);
  executor.spin();
  rclcpp::shutdown();
  return 0;
}

注释部分为demo2测试程序
因为是多个node执行在一个main函数中，需要MultiThreadedExecutor

5.3 编译

colcon build  --packages-up-to topic

5.4 运行

source环境变量

source install/setup.zsh

方式1

cd install/topic/lib/topic/
./tutorial.topic.tutorial.topic.member_function_test

方式2

ros2 launch topic tutorials_topic_demo2_member_function_test_launch.py

以后推荐使用launch文件启动程序

5.5 运行结果

tutorials_topic.demo5

6 tutorial 6(订阅器-lambda_test)

6.1 功能介绍

创建一个消息发布者（处理函数是lambda表达式），每隔500ms发布一次消息“’Hello, world!”，而接受者订阅器每隔500ms会收到发布者的数据信息

6.2 代码

头文件tutorials_topic_demo3_lambda_test.hpp

class MinimalPublisherWithLambda : public rclcpp::Node
{
public:
  MinimalPublisherWithLambda();

private:
  rclcpp::TimerBase::SharedPtr timer_;
  rclcpp::Publisher<std_msgs::msg::String>::SharedPtr publisher_;
  size_t count_;
};

class MinimalSubscriberWithLambda : public rclcpp::Node
{
public:
  MinimalSubscriberWithLambda();

private:
  rclcpp::Subscription<std_msgs::msg::String>::SharedPtr subscription_;
};

源文件tutorials_topic_demo3_lambda_test.cpp

MinimalPublisherWithLambda::MinimalPublisherWithLambda()
 : Node("lambda_minimal_publisher"), count_(0)
{
    publisher_ = this->create_publisher<std_msgs::msg::String>("topic", 10);
    auto timer_callback = [this]() -> void {
            auto message = std_msgs::msg::String();
            message.data = "Hello, world! " + std::to_string(this->count_++);
            RCLCPP_INFO(this->get_logger(), "Publishing: '%s'", message.data.c_str());
            this->publisher_->publish(message);
        };
    timer_ = this->create_wall_timer(500ms, timer_callback);
}


MinimalSubscriberWithLambda::MinimalSubscriberWithLambda()
: Node("labmbda_minimal_subscriber")
{
    subscription_ = this->create_subscription<std_msgs::msg::String>("topic", 10,
        [this](std_msgs::msg::String::UniquePtr msg) {
            RCLCPP_INFO(this->get_logger(), "I heard: '%s'", msg->data.c_str());
        });
}

测试文件tutorials_topic_demo3_lambda_test.cpp

#include "topic/tutorials_topic_demo3_lambda.hpp"

// int main(int argc, char ** argv)
// {
//   rclcpp::init(argc, argv);
//   auto empty_node = std::make_shared<ros2_tutorials::topic::MinimalPublisherWithLambda>();
//   rclcpp::spin(empty_node);
//   rclcpp::shutdown();
//   return 0;
// }

int main(int argc, char * argv[])
{
  rclcpp::init(argc, argv);

  // You MUST use the MultiThreadedExecutor to use, well, multiple threads
  rclcpp::executors::MultiThreadedExecutor executor;
  auto publisher_node = std::make_shared<ros2_tutorials::topic::MinimalPublisherWithLambda>();
  auto subscriber_node = std::make_shared<ros2_tutorials::topic::MinimalSubscriberWithLambda>();  // This contains BOTH subscriber callbacks.
                                                        // They will still run on different threads
                                                        // One Node. Two callbacks. Two Threads
  executor.add_node(publisher_node);
  executor.add_node(subscriber_node);
  executor.spin();
  rclcpp::shutdown();
  return 0;
}

6.3 编译

colcon build  --packages-up-to topic

6.4 运行

source环境变量

source install/setup.zsh

运行命令

ros2 launch topic tutorials_topic_demo3_lambda_test_launch.py

6.5 运行结果

tutorials_topic.member_function_test

7 tutorial 7(订阅器-member_function_with_topic_statistics)

7.1 功能介绍

创建一个消息发布者（处理函数是lambda表达式），每隔500ms发布一次消息“’Hello, world!”，而接受者订阅器每隔500ms会收到发布者的数据信息

7.2 代码

头文件tutorials_topic_demo5_member_function_with_topic_statistics.hpp

class MinimalSubscriberWithTopicStatistics : public rclcpp::Node
{
public:
  MinimalSubscriberWithTopicStatistics();

private:
  void HandleTopicCallback(const std_msgs::msg::String::SharedPtr msg) const;

  rclcpp::Subscription<std_msgs::msg::String>::SharedPtr subscription_;
};

源文件tutorials_topic_demo5_member_function_with_topic_statistics.cpp

MinimalSubscriberWithTopicStatistics::MinimalSubscriberWithTopicStatistics()
: Node("minimal_subscriber_with_topic_statistics")
{
    // manually enable topic statistics via options
    auto options = rclcpp::SubscriptionOptions();
    options.topic_stats_options.state = rclcpp::TopicStatisticsState::Enable;

    // configure the collection window and publish period (default 1s)
    options.topic_stats_options.publish_period = std::chrono::seconds(10);

    // configure the topic name (default '/statistics')
    // options.topic_stats_options.publish_topic = "/topic_statistics"

    auto callback = [this](std_msgs::msg::String::SharedPtr msg) {
        this->HandleTopicCallback(msg);
    };

    subscription_ = this->create_subscription<std_msgs::msg::String>(
        "topic", 10, callback, options);
}

void MinimalSubscriberWithTopicStatistics::HandleTopicCallback(
    const std_msgs::msg::String::SharedPtr msg) const
{
    RCLCPP_INFO(this->get_logger(), "I heard: '%s'", msg->data.c_str());
}

测试文件tutorials_topic_demo5_member_function_with_topic_statistics_test.cpp

#include "topic/tutorials_topic_demo5_member_function_with_topic_statistics.hpp"
#include "topic/tutorials_topic_demo2_member_function.hpp"

int main(int argc, char * argv[])
{
  rclcpp::init(argc, argv);

  // You MUST use the MultiThreadedExecutor to use, well, multiple threads
  rclcpp::executors::MultiThreadedExecutor executor;
  auto publisher_node = std::make_shared<ros2_tutorials::topic::MinimalPublisher>();
  auto subscriber_node = std::make_shared<ros2_tutorials::topic::MinimalSubscriberWithTopicStatistics>();  // This contains BOTH subscriber callbacks.
                                                        // They will still run on different threads
                                                        // One Node. Two callbacks. Two Threads
  executor.add_node(publisher_node);
  executor.add_node(subscriber_node);
  executor.spin();
  rclcpp::shutdown();
  return 0;
}

7.3 编译

colcon build  --packages-up-to topic

7.4 运行

source环境变量

source install/setup.zsh

运行命令

ros2 launch topic tutorials.topic.demo5_member_function_with_topic_statistics_test.launch.py

7.5 运行结果

tutorials_topic.demo5

8 tutorial 8(订阅器-member_function_with_unique_network_flow_endpoints)

8.1 功能介绍

8.2 代码

头文件tutorials_topic_demo6_member_function_with_unique_network_flow_endpoints.hpp.

class MinimalPublisherWithUniqueNetworkFlowEndpoints : public rclcpp::Node
{
public:
  MinimalPublisherWithUniqueNetworkFlowEndpoints();

private:
  void timer_1_callback();
  void timer_2_callback();

  /// Print network flow endpoints in JSON-like format
  void print_network_flow_endpoints(
    const std::vector<rclcpp::NetworkFlowEndpoint> & network_flow_endpoints) const;

  rclcpp::TimerBase::SharedPtr timer_1_;
  rclcpp::TimerBase::SharedPtr timer_2_;
  rclcpp::Publisher<std_msgs::msg::String>::SharedPtr publisher_1_;
  rclcpp::Publisher<std_msgs::msg::String>::SharedPtr publisher_2_;
  size_t count_1_;
  size_t count_2_;
};

class MinimalSubscriberWithUniqueNetworkFlowEndpoints : public rclcpp::Node
{
public:
  MinimalSubscriberWithUniqueNetworkFlowEndpoints();

private:
  void topic_1_callback(const std_msgs::msg::String::SharedPtr msg) const;
  void topic_2_callback(const std_msgs::msg::String::SharedPtr msg) const;

  /// Print network flow endpoints in JSON-like format
  void print_network_flow_endpoints(
    const std::vector<rclcpp::NetworkFlowEndpoint> & network_flow_endpoints) const;

  rclcpp::Subscription<std_msgs::msg::String>::SharedPtr subscription_1_;
  rclcpp::Subscription<std_msgs::msg::String>::SharedPtr subscription_2_;
};

源文件tutorials_topic_demo6_member_function_with_unique_network_flow_endpoints.cpp

MinimalPublisherWithUniqueNetworkFlowEndpoints::MinimalPublisherWithUniqueNetworkFlowEndpoints()
: Node("minimal_publisher_with_unique_network_flow_endpoints"), count_1_(0), count_2_(0)
{
    // Create publisher with unique network flow endpoints
    // Enable unique network flow endpoints via options
    auto options_1 = rclcpp::PublisherOptions();
    options_1.require_unique_network_flow_endpoints =
        RMW_UNIQUE_NETWORK_FLOW_ENDPOINTS_OPTIONALLY_REQUIRED;
    publisher_1_ = this->create_publisher<std_msgs::msg::String>("topic_1", 10, options_1);
    timer_1_ = this->create_wall_timer(
        500ms, std::bind(&MinimalPublisherWithUniqueNetworkFlowEndpoints::timer_1_callback, this));

    // Create publisher without unique network flow endpoints
    // Unique network flow endpoints are disabled in default options
    auto options_2 = rclcpp::PublisherOptions();
    publisher_2_ = this->create_publisher<std_msgs::msg::String>("topic_2", 10);
    timer_2_ = this->create_wall_timer(
        1000ms, std::bind(&MinimalPublisherWithUniqueNetworkFlowEndpoints::timer_2_callback, this));

    // Get network flow endpoints
    auto network_flow_endpoints_1 = publisher_1_->get_network_flow_endpoints();
    auto network_flow_endpoints_2 = publisher_2_->get_network_flow_endpoints();

    // Print network flow endpoints
    print_network_flow_endpoints(network_flow_endpoints_1);
    print_network_flow_endpoints(network_flow_endpoints_2);
}


void MinimalPublisherWithUniqueNetworkFlowEndpoints::timer_1_callback()
{
    auto message = std_msgs::msg::String();
    message.data = "Hello, world! " + std::to_string(count_1_++);

    RCLCPP_INFO(
        this->get_logger(), "Publishing: '%s'", message.data.c_str());
    publisher_1_->publish(message);
}

void MinimalPublisherWithUniqueNetworkFlowEndpoints::timer_2_callback()
{
    auto message = std_msgs::msg::String();
    message.data = "Hej, världen! " + std::to_string(count_2_++);

    RCLCPP_INFO(
        this->get_logger(), "Publishing: '%s'", message.data.c_str());
    publisher_2_->publish(message);
}

/// Print network flow endpoints in JSON-like format
void MinimalPublisherWithUniqueNetworkFlowEndpoints::print_network_flow_endpoints(
    const std::vector<rclcpp::NetworkFlowEndpoint> & network_flow_endpoints) const
{
    std::ostringstream stream;
    stream << "{\"networkFlowEndpoints\": [";
    bool comma_skip = true;
    for (auto network_flow_endpoint : network_flow_endpoints) {
        if (comma_skip) {
        comma_skip = false;
        } else {
        stream << ",";
        }
        stream << network_flow_endpoint;
    }
    stream << "]}";
    RCLCPP_INFO(
        this->get_logger(), "%s",
        stream.str().c_str());
}
  

MinimalSubscriberWithUniqueNetworkFlowEndpoints::MinimalSubscriberWithUniqueNetworkFlowEndpoints()
: Node("minimal_subscriber_with_unique_network_flow_endpoints")
{
    try 
    {
        // Create subscription with unique network flow endpoints
        // Enable unique network flow endpoints via options
        // Since option is strict, expect exception
        auto options_1 = rclcpp::SubscriptionOptions();
        options_1.require_unique_network_flow_endpoints =
        RMW_UNIQUE_NETWORK_FLOW_ENDPOINTS_STRICTLY_REQUIRED;

        subscription_1_ = this->create_subscription<std_msgs::msg::String>(
        "topic_1", 10, std::bind(
            &MinimalSubscriberWithUniqueNetworkFlowEndpoints::topic_1_callback, this,
            _1), options_1);

        // Create subscription without unique network flow endpoints
        // Unique network flow endpoints are disabled by default
        auto options_2 = rclcpp::SubscriptionOptions();
        subscription_2_ = this->create_subscription<std_msgs::msg::String>(
        "topic_2", 10, std::bind(
            &MinimalSubscriberWithUniqueNetworkFlowEndpoints::topic_2_callback, this,
            _1), options_2);

        // Get network flow endpoints
        auto network_flow_endpoints_1 = subscription_1_->get_network_flow_endpoints();
        auto network_flow_endpoints_2 = subscription_2_->get_network_flow_endpoints();

        // Check if network flow endpoints are unique
        for (auto network_flow_endpoint_1 : network_flow_endpoints_1) {
        for (auto network_flow_endpoint_2 : network_flow_endpoints_2) {
            if (network_flow_endpoint_1 == network_flow_endpoint_2) {
            RCLCPP_ERROR(
                this->get_logger(), "Network flow endpoints across subscriptions are not unique");
            break;
            }
        }
        }

        // Print network flow endpoints
        print_network_flow_endpoints(network_flow_endpoints_1);
        print_network_flow_endpoints(network_flow_endpoints_2);
    } catch (const rclcpp::exceptions::RCLError & e) {
        RCLCPP_ERROR(
        this->get_logger(),
        "Error: %s",
        e.what());
    }
}


void MinimalSubscriberWithUniqueNetworkFlowEndpoints::topic_1_callback(
    const std_msgs::msg::String::SharedPtr msg) const
{
    RCLCPP_INFO(this->get_logger(), "Topic 1 news: '%s'", msg->data.c_str());
}

void MinimalSubscriberWithUniqueNetworkFlowEndpoints::topic_2_callback(
    const std_msgs::msg::String::SharedPtr msg) const
{
    RCLCPP_INFO(this->get_logger(), "Topic 2 news: '%s'", msg->data.c_str());
}

/// Print network flow endpoints in JSON-like format
void MinimalSubscriberWithUniqueNetworkFlowEndpoints::print_network_flow_endpoints(
    const std::vector<rclcpp::NetworkFlowEndpoint> & network_flow_endpoints) const
{
    std::ostringstream stream;
    stream << "{\"networkFlowEndpoints\": [";
    bool comma_skip = true;
    for (auto network_flow_endpoint : network_flow_endpoints) {
        if (comma_skip) {
        comma_skip = false;
        } else {
        stream << ",";
        }
        stream << network_flow_endpoint;
    }
    stream << "]}";
    RCLCPP_INFO(
        this->get_logger(), "%s",
        stream.str().c_str());
}

测试文件tutorials_topic_demo6_member_function_with_unique_network_flow_endpoints.cpp

#include "topic/tutorials_topic_demo6_member_function_with_unique_network_flow_endpoints.hpp"

#include "topic/tutorials_topic_demo5_member_function_with_topic_statistics.hpp"
#include "topic/tutorials_topic_demo2_member_function.hpp"

int main(int argc, char * argv[])
{
  rclcpp::init(argc, argv);

  // You MUST use the MultiThreadedExecutor to use, well, multiple threads
  rclcpp::executors::MultiThreadedExecutor executor;
  auto publisher_node = std::make_shared<ros2_tutorials::topic::MinimalPublisherWithUniqueNetworkFlowEndpoints>();
  auto subscriber_node = std::make_shared<ros2_tutorials::topic::MinimalSubscriberWithUniqueNetworkFlowEndpoints>();  // This contains BOTH subscriber callbacks.
                                                        // They will still run on different threads
                                                        // One Node. Two callbacks. Two Threads
  executor.add_node(publisher_node);
  executor.add_node(subscriber_node);
  executor.spin();
  rclcpp::shutdown();
  return 0;
}

8.3 编译

colcon build  --packages-up-to topic

8.4 运行

source环境变量

source install/setup.zsh

运行命令

ros2 launch topic tutorials.topic.demo6_member_function_with_unique_network_flow_endpoints_test.launch.py

8.5 运行结果

CHANGELOG

No CHANGELOG found.

Wiki Tutorials

This package does not provide any links to tutorials in it's rosindex metadata. You can check on the ROS Wiki Tutorials page for the package.

Package Dependencies

Deps	Name
	rclcpp
	std_msgs
	rcutils
	ament_cmake
	ament_lint_auto
	ament_lint_common

System Dependencies

No direct system dependencies.

Dependant Packages

No known dependants.

Launch files

launch/tutorials_topic_demo1_initial_env_test.launch

Messages

No message files found.

Services

No service files found

Plugins

No plugins found.

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API Docs Browse Code

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topic package from openrobotics repo

Package Summary

Repository Summary

Package Description

Additional Links

Maintainers

Authors

1 tutorial 1(initial_env_test)

1.1 功能介绍

1.2 代码

1.3 编译

1.4 运行

1.5 运行结果

2 tutorial 2(member_function_test)

2.1 功能介绍

2.2 代码

2.3 编译

2.4 运行

2.5 运行结果

3 tutorial 3(lambda_test)

3.1 功能介绍

3.2 代码

3.3 编译

3.4 运行

3.5 运行结果

4 tutorial 4(lambda_test)

4.1 功能介绍

4.2 代码

4.3 编译

4.4 运行

4.5 运行结果

5 tutorial 5(订阅器member_function)

5.1 功能介绍

5.2 代码

5.3 编译

5.4 运行

5.5 运行结果

6 tutorial 6(订阅器-lambda_test)

6.1 功能介绍

6.2 代码

6.3 编译

6.4 运行

6.5 运行结果

7 tutorial 7(订阅器-member_function_with_topic_statistics)

7.1 功能介绍

7.2 代码

7.3 编译

7.4 运行

7.5 运行结果

8 tutorial 8(订阅器-member_function_with_unique_network_flow_endpoints)

8.1 功能介绍

8.2 代码

8.3 编译

8.4 运行

8.5 运行结果

Wiki Tutorials

Package Dependencies

System Dependencies

Dependant Packages

Launch files

Messages

Services

Plugins

Recent questions tagged topic at Robotics Stack Exchange

Recent questions tagged `topic` at Robotics Stack Exchange