simplify code

Author: facontidavide

behaviortree_ros2/include/behaviortree_ros2/tree_execution_server.hpp

@@ -66,8 +66,8 @@ class TreeExecutionServer
   /// @brief The payload received in the last goal
   const std::string& goalPayload() const;
 
-  /// @brief Tree being executed, nullptr if it doesn't exist, yet.
-  BT::Tree* tree();
+  /// @brief Tree being executed.
+  const BT::Tree& tree() const;
 
   /// @brief Pointer to the global blackboard
   BT::Blackboard::Ptr globalBlackboard();

behaviortree_ros2/src/tree_execution_server.cpp

@@ -32,8 +32,6 @@ struct TreeExecutionServer::Pimpl
 {
   rclcpp_action::Server<ExecuteTree>::SharedPtr action_server;
   std::thread action_thread;
-  // thread safe bool to keep track of cancel requests
-  std::atomic<bool> cancel_requested{ false };
 
   std::shared_ptr<bt_server::ParamListener> param_listener;
   bt_server::Params params;
@@ -43,7 +41,7 @@ struct TreeExecutionServer::Pimpl
 
   std::string tree_name;
   std::string payload;
-  std::shared_ptr<BT::Tree> tree;
+  BT::Tree tree;
   BT::Blackboard::Ptr global_blackboard;
   bool factory_initialized_ = false;
 
@@ -123,7 +121,6 @@ TreeExecutionServer::handle_goal(const rclcpp_action::GoalUUID& /* uuid */,
 {
   RCLCPP_INFO(kLogger, "Received goal request to execute Behavior Tree: %s",
               goal->target_tree.c_str());
-  p_->cancel_requested = false;
   return rclcpp_action::GoalResponse::ACCEPT_AND_EXECUTE;
 }
 
@@ -137,7 +134,6 @@ rclcpp_action::CancelResponse TreeExecutionServer::handle_cancel(
                          "processing one.");
     return rclcpp_action::CancelResponse::REJECT;
   }
-  p_->cancel_requested = true;
   return rclcpp_action::CancelResponse::ACCEPT;
 }
 
@@ -172,30 +168,29 @@ void TreeExecutionServer::execute(
     // This blackboard will be owned by "MainTree". It parent is p_->global_blackboard
     auto root_blackboard = BT::Blackboard::create(p_->global_blackboard);
 
-    p_->tree = std::make_shared<BT::Tree>();
-    *(p_->tree) = p_->factory.createTree(goal->target_tree, root_blackboard);
+    p_->tree = p_->factory.createTree(goal->target_tree, root_blackboard);
     p_->tree_name = goal->target_tree;
     p_->payload = goal->payload;
 
     // call user defined function after the tree has been created
-    onTreeCreated(*p_->tree);
+    onTreeCreated(p_->tree);
     p_->groot_publisher.reset();
     p_->groot_publisher =
-        std::make_shared<BT::Groot2Publisher>(*(p_->tree), p_->params.groot2_port);
+        std::make_shared<BT::Groot2Publisher>(p_->tree, p_->params.groot2_port);
 
     // Loop until the tree is done or a cancel is requested
     const auto period =
         std::chrono::milliseconds(static_cast<int>(1000.0 / p_->params.tick_frequency));
     auto loop_deadline = std::chrono::steady_clock::now() + period;
 
     // operations to be done if the tree execution is aborted, either by
-    // cancel_requested_ or by onLoopAfterTick()
+    // cancel requested or by onLoopAfterTick()
     auto stop_action = [this, &action_result](BT::NodeStatus status,
                                               const std::string& message) {
       action_result->node_status = ConvertNodeStatus(status);
       action_result->return_message = message;
       RCLCPP_WARN(kLogger, action_result->return_message.c_str());
-      p_->tree->haltTree();
+      p_->tree.haltTree();
       // override the message value if the user defined function returns it
       if(auto msg = onTreeExecutionCompleted(status, true))
       {
@@ -205,15 +200,15 @@ void TreeExecutionServer::execute(
 
     while(rclcpp::ok() && status == BT::NodeStatus::RUNNING)
     {
-      if(p_->cancel_requested)
+      if(goal_handle->is_canceling())
       {
         stop_action(status, "Action Server canceling and halting Behavior Tree");
         goal_handle->canceled(action_result);
         return;
       }
 
       // tick the tree once and publish the action feedback
-      status = p_->tree->tickExactlyOnce();
+      status = p_->tree.tickExactlyOnce();
 
       if(const auto res = onLoopAfterTick(status); res.has_value())
       {
@@ -232,7 +227,7 @@ void TreeExecutionServer::execute(
       const auto now = std::chrono::steady_clock::now();
       if(now < loop_deadline)
       {
-        p_->tree->sleep(loop_deadline - now);
+        p_->tree.sleep(loop_deadline - now);
       }
       loop_deadline += period;
     }
@@ -245,19 +240,32 @@ void TreeExecutionServer::execute(
     return;
   }
 
-  // set the node_status result to the action
-  action_result->node_status = ConvertNodeStatus(status);
-
   // Call user defined onTreeExecutionCompleted function.
   // Override the message value if the user defined function returns it
   if(auto msg = onTreeExecutionCompleted(status, false))
   {
     action_result->return_message = msg.value();
   }
+  else
+  {
+    action_result->return_message =
+        std::string("Tree finished with status: ") + BT::toStr(status);
+  }
+
+  // set the node_status result to the action
+  action_result->node_status = ConvertNodeStatus(status);
 
   // return success or aborted for the action result
-  RCLCPP_INFO(kLogger, "BT finished with status: %s", BT::toStr(status).c_str());
-  goal_handle->succeed(action_result);
+  if(status == BT::NodeStatus::SUCCESS)
+  {
+    RCLCPP_INFO(kLogger, action_result->return_message.c_str());
+    goal_handle->succeed(action_result);
+  }
+  else
+  {
+    RCLCPP_ERROR(kLogger, action_result->return_message.c_str());
+    goal_handle->abort(action_result);
+  }
 }
 
 const std::string& TreeExecutionServer::treeName() const
@@ -270,9 +278,9 @@ const std::string& TreeExecutionServer::goalPayload() const
   return p_->payload;
 }
 
-BT::Tree* TreeExecutionServer::tree()
+const BT::Tree& TreeExecutionServer::tree() const
 {
-  return p_->tree ? p_->tree.get() : nullptr;
+  return p_->tree;
 }
 
 BT::Blackboard::Ptr TreeExecutionServer::globalBlackboard()