export_interfaces_2() virtual for custom interface export

hardware_interface/include/hardware_interface/actuator_interface.hpp

@@ -159,6 +159,20 @@ class ActuatorInterface : public rclcpp_lifecycle::node_interfaces::LifecycleNod
     return {};
   }
 
+  /**
+   * Override this method to export custom StateInterfaces which are not defined in the URDF file.
+   *
+   *  Note method name is going to be changed to export_state_interfaces() as soon as the deprecated
+   * version is removed.
+   *
+   * \return vector of shared pointers to the created and stored StateInterfaces
+   */
+  virtual std::vector<std::shared_ptr<StateInterface>> export_state_interfaces_2()
+  {
+    // return empty vector by default.
+    return {};
+  }
+
   /**
    * Default implementation for exporting the StateInterfaces. The StateInterfaces are created
    * according to the InterfaceDescription. The memory accessed by the controllers and hardware is
@@ -168,7 +182,7 @@ class ActuatorInterface : public rclcpp_lifecycle::node_interfaces::LifecycleNod
    */
   virtual std::vector<std::shared_ptr<StateInterface>> on_export_state_interfaces()
   {
-    std::vector<std::shared_ptr<StateInterface>> state_interfaces;
+    std::vector<std::shared_ptr<StateInterface>> state_interfaces = export_state_interfaces_2();
     state_interfaces.reserve(joint_state_interfaces_.size());
 
     for (const auto & [name, descr] : joint_state_interfaces_)
@@ -204,6 +218,20 @@ class ActuatorInterface : public rclcpp_lifecycle::node_interfaces::LifecycleNod
     return {};
   }
 
+  /**
+   * Override this method to export custom CommandInterfaces which are not defined in the URDF file.
+   *
+   *  Note method name is going to be changed to export_command_interfaces() as soon as the
+   * deprecated version is removed.
+   *
+   * \return vector of shared pointers to the created and stored StateInterfaces
+   */
+  virtual std::vector<std::shared_ptr<CommandInterface>> export_command_interfaces_2()
+  {
+    // return empty vector by default.
+    return {};
+  }
+
   /**
    * Default implementation for exporting the CommandInterfaces. The CommandInterfaces are created
    * according to the InterfaceDescription. The memory accessed by the controllers and hardware is
@@ -213,7 +241,8 @@ class ActuatorInterface : public rclcpp_lifecycle::node_interfaces::LifecycleNod
    */
   virtual std::vector<std::shared_ptr<CommandInterface>> on_export_command_interfaces()
   {
-    std::vector<std::shared_ptr<CommandInterface>> command_interfaces;
+    std::vector<std::shared_ptr<CommandInterface>> command_interfaces =
+      export_command_interfaces_2();
     command_interfaces.reserve(joint_command_interfaces_.size());
 
     for (const auto & [name, descr] : joint_command_interfaces_)

hardware_interface/include/hardware_interface/hardware_info.hpp

@@ -38,9 +38,9 @@ struct InterfaceInfo
   std::string max;
   /// (Optional) Initial value of the interface.
   std::string initial_value;
-  /// (Optional) The datatype of the interface, e.g. "bool", "int". Used by GPIOs.
+  /// (Optional) The datatype of the interface, e.g. "bool", "int".
   std::string data_type;
-  /// (Optional) If the handle is an array, the size of the array. Used by GPIOs.
+  /// (Optional) If the handle is an array, the size of the array.
   int size;
 };
 
@@ -118,11 +118,6 @@ struct InterfaceDescription
    */
   std::string prefix_name;
 
-  /**
-   * What type of component is exported: joint, sensor or gpio
-   */
-  std::string component_type;
-
   /**
    * Information about the Interface type (position, velocity,...) as well as limits and so on.
    */

hardware_interface/include/hardware_interface/sensor_interface.hpp

@@ -143,6 +143,20 @@ class SensorInterface : public rclcpp_lifecycle::node_interfaces::LifecycleNodeI
     return {};
   }
 
+  /**
+   * Override this method to export custom StateInterfaces which are not defined in the URDF file.
+   *
+   *  Note method name is going to be changed to export_state_interfaces() as soon as the deprecated
+   * version is removed.
+   *
+   * \return vector of shared pointers to the created and stored StateInterfaces
+   */
+  virtual std::vector<std::shared_ptr<StateInterface>> export_state_interfaces_2()
+  {
+    // return empty vector by default.
+    return {};
+  }
+
   /**
    * Default implementation for exporting the StateInterfaces. The StateInterfaces are created
    * according to the InterfaceDescription. The memory accessed by the controllers and hardware is
@@ -152,7 +166,7 @@ class SensorInterface : public rclcpp_lifecycle::node_interfaces::LifecycleNodeI
    */
   virtual std::vector<std::shared_ptr<StateInterface>> on_export_state_interfaces()
   {
-    std::vector<std::shared_ptr<StateInterface>> state_interfaces;
+    std::vector<std::shared_ptr<StateInterface>> state_interfaces = export_state_interfaces_2();
     state_interfaces.reserve(sensor_state_interfaces_.size());
 
     for (const auto & [name, descr] : sensor_state_interfaces_)

hardware_interface/include/hardware_interface/system_interface.hpp

@@ -178,16 +178,30 @@ class SystemInterface : public rclcpp_lifecycle::node_interfaces::LifecycleNodeI
     return {};
   }
 
+  /**
+   * Override this method to export custom StateInterfaces which are not defined in the URDF file.
+   *
+   *  Note method name is going to be changed to export_state_interfaces() as soon as the deprecated
+   * version is removed.
+   *
+   * \return vector of shared pointers to the created and stored StateInterfaces
+   */
+  virtual std::vector<std::shared_ptr<StateInterface>> export_state_interfaces_2()
+  {
+    // return empty vector by default.
+    return {};
+  }
+
   /**
    * Default implementation for exporting the StateInterfaces. The StateInterfaces are created
    * according to the InterfaceDescription. The memory accessed by the controllers and hardware is
    * assigned here and resides in the system_interface.
    *
    * \return vector of shared pointers to the created and stored StateInterfaces
    */
-  virtual std::vector<std::shared_ptr<StateInterface>> on_export_state_interfaces()
+  std::vector<std::shared_ptr<StateInterface>> on_export_state_interfaces()
   {
-    std::vector<std::shared_ptr<StateInterface>> state_interfaces;
+    std::vector<std::shared_ptr<StateInterface>> state_interfaces = export_state_interfaces_2();
     state_interfaces.reserve(
       joint_state_interfaces_.size() + sensor_state_interfaces_.size() +
       gpio_state_interfaces_.size());
@@ -237,16 +251,31 @@ class SystemInterface : public rclcpp_lifecycle::node_interfaces::LifecycleNodeI
     return {};
   }
 
+  /**
+   * Override this method to export custom CommandInterfaces which are not defined in the URDF file.
+   *
+   *  Note method name is going to be changed to export_command_interfaces() as soon as the
+   * deprecated version is removed.
+   *
+   * \return vector of shared pointers to the created and stored StateInterfaces
+   */
+  virtual std::vector<std::shared_ptr<CommandInterface>> export_command_interfaces_2()
+  {
+    // return empty vector by default.
+    return {};
+  }
+
   /**
    * Default implementation for exporting the CommandInterfaces. The CommandInterfaces are created
    * according to the InterfaceDescription. The memory accessed by the controllers and hardware is
    * assigned here and resides in the system_interface.
    *
    * \return vector of shared pointers to the created and stored CommandInterfaces
    */
-  virtual std::vector<std::shared_ptr<CommandInterface>> on_export_command_interfaces()
+  std::vector<std::shared_ptr<CommandInterface>> on_export_command_interfaces()
   {
-    std::vector<std::shared_ptr<CommandInterface>> command_interfaces;
+    std::vector<std::shared_ptr<CommandInterface>> command_interfaces =
+      export_command_interfaces_2();
     command_interfaces.reserve(joint_command_interfaces_.size() + gpio_command_interfaces_.size());
 
     for (const auto & [name, descr] : joint_command_interfaces_)