.. _program_listing_file__tmp_ws_src_image_common_image_transport_include_image_transport_simple_publisher_plugin.hpp:

Program Listing for File simple_publisher_plugin.hpp
====================================================

|exhale_lsh| :ref:`Return to documentation for file <file__tmp_ws_src_image_common_image_transport_include_image_transport_simple_publisher_plugin.hpp>` (``/tmp/ws/src/image_common/image_transport/include/image_transport/simple_publisher_plugin.hpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   // Copyright (c) 2009, Willow Garage, Inc.
   //
   // Redistribution and use in source and binary forms, with or without
   // modification, are permitted provided that the following conditions are met:
   //
   //    * Redistributions of source code must retain the above copyright
   //      notice, this list of conditions and the following disclaimer.
   //
   //    * Redistributions in binary form must reproduce the above copyright
   //      notice, this list of conditions and the following disclaimer in the
   //      documentation and/or other materials provided with the distribution.
   //
   //    * Neither the name of the Willow Garage nor the names of its
   //      contributors may be used to endorse or promote products derived from
   //      this software without specific prior written permission.
   //
   // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
   // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   // POSSIBILITY OF SUCH DAMAGE.
   
   #ifndef IMAGE_TRANSPORT__SIMPLE_PUBLISHER_PLUGIN_HPP_
   #define IMAGE_TRANSPORT__SIMPLE_PUBLISHER_PLUGIN_HPP_
   
   #include <memory>
   #include <string>
   
   #include "rclcpp/node.hpp"
   #include "rclcpp/logger.hpp"
   #include "rclcpp/logging.hpp"
   
   #include "image_transport/publisher_plugin.hpp"
   #include "image_transport/visibility_control.hpp"
   
   namespace image_transport
   {
   
   template<class M>
   class SimplePublisherPlugin : public PublisherPlugin
   {
   public:
     virtual ~SimplePublisherPlugin() {}
   
     virtual size_t getNumSubscribers() const
     {
       if (simple_impl_) {
         return simple_impl_->pub_->get_subscription_count();
       }
       return 0;
     }
   
     virtual std::string getTopic() const
     {
       if (simple_impl_) {return simple_impl_->pub_->get_topic_name();}
       return std::string();
     }
   
     virtual void publish(const sensor_msgs::msg::Image & message) const
     {
       if (!simple_impl_ || !simple_impl_->pub_) {
         auto logger = simple_impl_ ? simple_impl_->logger_ : rclcpp::get_logger("image_transport");
         RCLCPP_ERROR(
           logger,
           "Call to publish() on an invalid image_transport::SimplePublisherPlugin");
         return;
       }
   
       publish(message, bindInternalPublisher(simple_impl_->pub_.get()));
     }
   
     virtual void shutdown()
     {
       simple_impl_.reset();
     }
   
   protected:
     virtual void advertiseImpl(
       rclcpp::Node * node, const std::string & base_topic,
       rmw_qos_profile_t custom_qos)
     {
       std::string transport_topic = getTopicToAdvertise(base_topic);
       simple_impl_ = std::make_unique<SimplePublisherPluginImpl>(node);
   
       RCLCPP_DEBUG(simple_impl_->logger_, "getTopicToAdvertise: %s", transport_topic.c_str());
       auto qos = rclcpp::QoS(rclcpp::QoSInitialization::from_rmw(custom_qos), custom_qos);
       simple_impl_->pub_ = node->create_publisher<M>(transport_topic, qos);
     }
   
     typedef std::function<void (const M &)> PublishFn;
   
     virtual void publish(
       const sensor_msgs::msg::Image & message,
       const PublishFn & publish_fn) const = 0;
   
     virtual std::string getTopicToAdvertise(const std::string & base_topic) const
     {
       return base_topic + "/" + getTransportName();
     }
   
   private:
     struct SimplePublisherPluginImpl
     {
       explicit SimplePublisherPluginImpl(rclcpp::Node * node)
       : node_(node),
         logger_(node->get_logger())
       {
       }
   
       rclcpp::Node * node_;
       rclcpp::Logger logger_;
       typename rclcpp::Publisher<M>::SharedPtr pub_;
     };
   
     std::unique_ptr<SimplePublisherPluginImpl> simple_impl_;
   
     typedef std::function<void (const sensor_msgs::msg::Image &)> ImagePublishFn;
   
     template<class PubT>
     PublishFn bindInternalPublisher(PubT * pub) const
     {
       // Bind PubT::publish(const Message&) as PublishFn
       typedef void (PubT::* InternalPublishMemFn)(const M &);
       InternalPublishMemFn internal_pub_mem_fn = &PubT::publish;
       return std::bind(internal_pub_mem_fn, pub, std::placeholders::_1);
     }
   };
   
   }  // namespace image_transport
   
   #endif  // IMAGE_TRANSPORT__SIMPLE_PUBLISHER_PLUGIN_HPP_