[fix] MGI server timeout, infinite duration by default (#349)

By setting the default server timeout duration to -1, the MoveGroupInterface is ensured to be ready to use after construction.

moveit_ros/planning_interface/move_group_interface/include/moveit/move_group_interface/move_group_interface.h

@@ -148,22 +148,22 @@ class MoveGroupInterface
         (which is the default type of callback queues used in ROS)
       \param tf_buffer. Specify a TF2_ROS Buffer instance to use. If not specified,
                         one will be constructed internally along with an internal TF2_ROS TransformListener
-      \param wait_for_servers. Timeout for connecting to action servers. Zero time means unlimited waiting.
+      \param wait_for_servers. Timeout for connecting to action servers. -1 time means unlimited waiting.
     */
   MoveGroupInterface(const rclcpp::Node::SharedPtr& node, const Options& opt,
                      const std::shared_ptr<tf2_ros::Buffer>& tf_buffer = std::shared_ptr<tf2_ros::Buffer>(),
-                     const rclcpp::Duration& wait_for_servers = rclcpp::Duration(0.0));
+                     const rclcpp::Duration& wait_for_servers = rclcpp::Duration(-1));
 
   /**
       \brief Construct a client for the MoveGroup action for a particular \e group.
 
       \param tf_buffer. Specify a TF2_ROS Buffer instance to use. If not specified,
                         one will be constructed internally along with an internal TF2_ROS TransformListener
-      \param wait_for_servers. Timeout for connecting to action servers. Zero time means unlimited waiting.
+      \param wait_for_servers. Timeout for connecting to action servers. -1 time means unlimited waiting.
     */
   MoveGroupInterface(const rclcpp::Node::SharedPtr& node, const std::string& group,
                      const std::shared_ptr<tf2_ros::Buffer>& tf_buffer = std::shared_ptr<tf2_ros::Buffer>(),
-                     const rclcpp::Duration& wait_for_servers = rclcpp::Duration(0.0));
+                     const rclcpp::Duration& wait_for_servers = rclcpp::Duration(-1));
 
   ~MoveGroupInterface();
 

moveit_ros/planning_interface/move_group_interface/src/move_group_interface.cpp

@@ -143,12 +143,8 @@ class MoveGroupInterface::MoveGroupInterfaceImpl
 
     current_state_monitor_ = getSharedStateMonitor(node_, robot_model_, tf_buffer_);
 
-    rclcpp::Time timeout_for_servers = pnode_->now() + wait_for_servers;
-    if (wait_for_servers == rclcpp::Duration(0.0))
-      timeout_for_servers = rclcpp::Time();  // wait for ever
-
     move_action_client_ = rclcpp_action::create_client<moveit_msgs::action::MoveGroup>(pnode_, move_group::MOVE_ACTION);
-    move_action_client_->wait_for_action_server(std::chrono::nanoseconds(timeout_for_servers.nanoseconds()));
+    move_action_client_->wait_for_action_server(wait_for_servers.to_chrono<std::chrono::duration<double>>());
     // TODO(JafarAbdi): Enable once moveit_ros_manipulation is ported
     // pick_action_client_ = rclcpp_action::create_client<moveit_msgs::action::Pickup>(
     //        node_, move_group::PICKUP_ACTION);
@@ -159,7 +155,7 @@ class MoveGroupInterface::MoveGroupInterfaceImpl
     //    place_action_client_->wait_for_action_server(std::chrono::nanoseconds(timeout_for_servers.nanoseconds()));
     execute_action_client_ =
         rclcpp_action::create_client<moveit_msgs::action::ExecuteTrajectory>(pnode_, move_group::EXECUTE_ACTION_NAME);
-    execute_action_client_->wait_for_action_server(std::chrono::nanoseconds(timeout_for_servers.nanoseconds()));
+    execute_action_client_->wait_for_action_server(wait_for_servers.to_chrono<std::chrono::duration<double>>());
 
     query_service_ =
         pnode_->create_client<moveit_msgs::srv::QueryPlannerInterfaces>(move_group::QUERY_PLANNERS_SERVICE_NAME);